github.com/mattyr/nomad@v0.3.3-0.20160919021406-3485a065154a/nomad/structs/structs.go

package structs

import (
	"bytes"
	"crypto/md5"
	"crypto/sha1"
	"crypto/sha256"
	"crypto/sha512"
	"encoding/hex"
	"errors"
	"fmt"
	"io"
	"path/filepath"
	"reflect"
	"regexp"
	"strconv"
	"strings"
	"time"

	"github.com/gorhill/cronexpr"
	"github.com/hashicorp/consul/api"
	"github.com/hashicorp/go-multierror"
	"github.com/hashicorp/go-version"
	"github.com/hashicorp/nomad/helper/args"
	"github.com/mitchellh/copystructure"
	"github.com/ugorji/go/codec"

	hcodec "github.com/hashicorp/go-msgpack/codec"
)

var (
	ErrNoLeader     = fmt.Errorf("No cluster leader")
	ErrNoRegionPath = fmt.Errorf("No path to region")
)

type MessageType uint8

const (
	NodeRegisterRequestType MessageType = iota
	NodeDeregisterRequestType
	NodeUpdateStatusRequestType
	NodeUpdateDrainRequestType
	JobRegisterRequestType
	JobDeregisterRequestType
	EvalUpdateRequestType
	EvalDeleteRequestType
	AllocUpdateRequestType
	AllocClientUpdateRequestType
	ReconcileJobSummariesRequestType
	VaultAccessorRegisterRequestType
	VaultAccessorDegisterRequestType
)

const (
	// IgnoreUnknownTypeFlag is set along with a MessageType
	// to indicate that the message type can be safely ignored
	// if it is not recognized. This is for future proofing, so
	// that new commands can be added in a way that won't cause
	// old servers to crash when the FSM attempts to process them.
	IgnoreUnknownTypeFlag MessageType = 128

	// ApiMajorVersion is returned as part of the Status.Version request.
	// It should be incremented anytime the APIs are changed in a way
	// that would break clients for sane client versioning.
	ApiMajorVersion = 1

	// ApiMinorVersion is returned as part of the Status.Version request.
	// It should be incremented anytime the APIs are changed to allow
	// for sane client versioning. Minor changes should be compatible
	// within the major version.
	ApiMinorVersion = 1

	ProtocolVersion = "protocol"
	APIMajorVersion = "api.major"
	APIMinorVersion = "api.minor"
)

// RPCInfo is used to describe common information about query
type RPCInfo interface {
	RequestRegion() string
	IsRead() bool
	AllowStaleRead() bool
}

// QueryOptions is used to specify various flags for read queries
type QueryOptions struct {
	// The target region for this query
	Region string

	// If set, wait until query exceeds given index. Must be provided
	// with MaxQueryTime.
	MinQueryIndex uint64

	// Provided with MinQueryIndex to wait for change.
	MaxQueryTime time.Duration

	// If set, any follower can service the request. Results
	// may be arbitrarily stale.
	AllowStale bool

	// If set, used as prefix for resource list searches
	Prefix string
}

func (q QueryOptions) RequestRegion() string {
	return q.Region
}

// QueryOption only applies to reads, so always true
func (q QueryOptions) IsRead() bool {
	return true
}

func (q QueryOptions) AllowStaleRead() bool {
	return q.AllowStale
}

type WriteRequest struct {
	// The target region for this write
	Region string
}

func (w WriteRequest) RequestRegion() string {
	// The target region for this request
	return w.Region
}

// WriteRequest only applies to writes, always false
func (w WriteRequest) IsRead() bool {
	return false
}

func (w WriteRequest) AllowStaleRead() bool {
	return false
}

// QueryMeta allows a query response to include potentially
// useful metadata about a query
type QueryMeta struct {
	// This is the index associated with the read
	Index uint64

	// If AllowStale is used, this is time elapsed since
	// last contact between the follower and leader. This
	// can be used to gauge staleness.
	LastContact time.Duration

	// Used to indicate if there is a known leader node
	KnownLeader bool
}

// WriteMeta allows a write response to include potentially
// useful metadata about the write
type WriteMeta struct {
	// This is the index associated with the write
	Index uint64
}

// NodeRegisterRequest is used for Node.Register endpoint
// to register a node as being a schedulable entity.
type NodeRegisterRequest struct {
	Node *Node
	WriteRequest
}

// NodeDeregisterRequest is used for Node.Deregister endpoint
// to deregister a node as being a schedulable entity.
type NodeDeregisterRequest struct {
	NodeID string
	WriteRequest
}

// NodeServerInfo is used to in NodeUpdateResponse to return Nomad server
// information used in RPC server lists.
type NodeServerInfo struct {
	// RPCAdvertiseAddr is the IP endpoint that a Nomad Server wishes to
	// be contacted at for RPCs.
	RPCAdvertiseAddr string

	// RpcMajorVersion is the major version number the Nomad Server
	// supports
	RPCMajorVersion int32

	// RpcMinorVersion is the minor version number the Nomad Server
	// supports
	RPCMinorVersion int32

	// Datacenter is the datacenter that a Nomad server belongs to
	Datacenter string
}

// NodeUpdateStatusRequest is used for Node.UpdateStatus endpoint
// to update the status of a node.
type NodeUpdateStatusRequest struct {
	NodeID string
	Status string
	WriteRequest
}

// NodeUpdateDrainRequest is used for updatin the drain status
type NodeUpdateDrainRequest struct {
	NodeID string
	Drain  bool
	WriteRequest
}

// NodeEvaluateRequest is used to re-evaluate the ndoe
type NodeEvaluateRequest struct {
	NodeID string
	WriteRequest
}

// NodeSpecificRequest is used when we just need to specify a target node
type NodeSpecificRequest struct {
	NodeID   string
	SecretID string
	QueryOptions
}

// JobRegisterRequest is used for Job.Register endpoint
// to register a job as being a schedulable entity.
type JobRegisterRequest struct {
	Job *Job

	// If EnforceIndex is set then the job will only be registered if the passed
	// JobModifyIndex matches the current Jobs index. If the index is zero, the
	// register only occurs if the job is new.
	EnforceIndex   bool
	JobModifyIndex uint64

	WriteRequest
}

// JobDeregisterRequest is used for Job.Deregister endpoint
// to deregister a job as being a schedulable entity.
type JobDeregisterRequest struct {
	JobID string
	WriteRequest
}

// JobEvaluateRequest is used when we just need to re-evaluate a target job
type JobEvaluateRequest struct {
	JobID string
	WriteRequest
}

// JobSpecificRequest is used when we just need to specify a target job
type JobSpecificRequest struct {
	JobID string
	QueryOptions
}

// JobListRequest is used to parameterize a list request
type JobListRequest struct {
	QueryOptions
}

// JobPlanRequest is used for the Job.Plan endpoint to trigger a dry-run
// evaluation of the Job.
type JobPlanRequest struct {
	Job  *Job
	Diff bool // Toggles an annotated diff
	WriteRequest
}

// JobSummaryRequest is used when we just need to get a specific job summary
type JobSummaryRequest struct {
	JobID string
	QueryOptions
}

// NodeListRequest is used to parameterize a list request
type NodeListRequest struct {
	QueryOptions
}

// EvalUpdateRequest is used for upserting evaluations.
type EvalUpdateRequest struct {
	Evals     []*Evaluation
	EvalToken string
	WriteRequest
}

// EvalDeleteRequest is used for deleting an evaluation.
type EvalDeleteRequest struct {
	Evals  []string
	Allocs []string
	WriteRequest
}

// EvalSpecificRequest is used when we just need to specify a target evaluation
type EvalSpecificRequest struct {
	EvalID string
	QueryOptions
}

// EvalAckRequest is used to Ack/Nack a specific evaluation
type EvalAckRequest struct {
	EvalID string
	Token  string
	WriteRequest
}

// EvalDequeueRequest is used when we want to dequeue an evaluation
type EvalDequeueRequest struct {
	Schedulers []string
	Timeout    time.Duration
	WriteRequest
}

// EvalListRequest is used to list the evaluations
type EvalListRequest struct {
	QueryOptions
}

// PlanRequest is used to submit an allocation plan to the leader
type PlanRequest struct {
	Plan *Plan
	WriteRequest
}

// AllocUpdateRequest is used to submit changes to allocations, either
// to cause evictions or to assign new allocaitons. Both can be done
// within a single transaction
type AllocUpdateRequest struct {
	// Alloc is the list of new allocations to assign
	Alloc []*Allocation

	// Job is the shared parent job of the allocations.
	// It is pulled out since it is common to reduce payload size.
	Job *Job

	WriteRequest
}

// AllocListRequest is used to request a list of allocations
type AllocListRequest struct {
	QueryOptions
}

// AllocSpecificRequest is used to query a specific allocation
type AllocSpecificRequest struct {
	AllocID string
	QueryOptions
}

// AllocsGetRequest is used to query a set of allocations
type AllocsGetRequest struct {
	AllocIDs []string
	QueryOptions
}

// PeriodicForceReqeuest is used to force a specific periodic job.
type PeriodicForceRequest struct {
	JobID string
	WriteRequest
}

// DeriveVaultTokenRequest is used to request wrapped Vault tokens for the
// following tasks in the given allocation
type DeriveVaultTokenRequest struct {
	NodeID   string
	SecretID string
	AllocID  string
	Tasks    []string
	QueryOptions
}

// VaultAccessorsRequest is used to operate on a set of Vault accessors
type VaultAccessorsRequest struct {
	Accessors []*VaultAccessor
}

// VaultAccessor is a reference to a created Vault token on behalf of
// an allocation's task.
type VaultAccessor struct {
	AllocID     string
	Task        string
	NodeID      string
	Accessor    string
	CreationTTL int

	// Raft Indexes
	CreateIndex uint64
}

// DeriveVaultTokenResponse returns the wrapped tokens for each requested task
type DeriveVaultTokenResponse struct {
	// Tasks is a mapping between the task name and the wrapped token
	Tasks map[string]string
	QueryMeta
}

// GenericRequest is used to request where no
// specific information is needed.
type GenericRequest struct {
	QueryOptions
}

// GenericResponse is used to respond to a request where no
// specific response information is needed.
type GenericResponse struct {
	WriteMeta
}

// VersionResponse is used for the Status.Version reseponse
type VersionResponse struct {
	Build    string
	Versions map[string]int
	QueryMeta
}

// JobRegisterResponse is used to respond to a job registration
type JobRegisterResponse struct {
	EvalID          string
	EvalCreateIndex uint64
	JobModifyIndex  uint64
	QueryMeta
}

// JobDeregisterResponse is used to respond to a job deregistration
type JobDeregisterResponse struct {
	EvalID          string
	EvalCreateIndex uint64
	JobModifyIndex  uint64
	QueryMeta
}

// NodeUpdateResponse is used to respond to a node update
type NodeUpdateResponse struct {
	HeartbeatTTL    time.Duration
	EvalIDs         []string
	EvalCreateIndex uint64
	NodeModifyIndex uint64

	// LeaderRPCAddr is the RPC address of the current Raft Leader.  If
	// empty, the current Nomad Server is in the minority of a partition.
	LeaderRPCAddr string

	// NumNodes is the number of Nomad nodes attached to this quorum of
	// Nomad Servers at the time of the response.  This value can
	// fluctuate based on the health of the cluster between heartbeats.
	NumNodes int32

	// Servers is the full list of known Nomad servers in the local
	// region.
	Servers []*NodeServerInfo

	QueryMeta
}

// NodeDrainUpdateResponse is used to respond to a node drain update
type NodeDrainUpdateResponse struct {
	EvalIDs         []string
	EvalCreateIndex uint64
	NodeModifyIndex uint64
	QueryMeta
}

// NodeAllocsResponse is used to return allocs for a single node
type NodeAllocsResponse struct {
	Allocs []*Allocation
	QueryMeta
}

// NodeClientAllocsResponse is used to return allocs meta data for a single node
type NodeClientAllocsResponse struct {
	Allocs map[string]uint64
	QueryMeta
}

// SingleNodeResponse is used to return a single node
type SingleNodeResponse struct {
	Node *Node
	QueryMeta
}

// JobListResponse is used for a list request
type NodeListResponse struct {
	Nodes []*NodeListStub
	QueryMeta
}

// SingleJobResponse is used to return a single job
type SingleJobResponse struct {
	Job *Job
	QueryMeta
}

// JobSummaryResponse is used to return a single job summary
type JobSummaryResponse struct {
	JobSummary *JobSummary
	QueryMeta
}

// JobListResponse is used for a list request
type JobListResponse struct {
	Jobs []*JobListStub
	QueryMeta
}

// JobPlanResponse is used to respond to a job plan request
type JobPlanResponse struct {
	// Annotations stores annotations explaining decisions the scheduler made.
	Annotations *PlanAnnotations

	// FailedTGAllocs is the placement failures per task group.
	FailedTGAllocs map[string]*AllocMetric

	// JobModifyIndex is the modification index of the job. The value can be
	// used when running `nomad run` to ensure that the Job wasn’t modified
	// since the last plan. If the job is being created, the value is zero.
	JobModifyIndex uint64

	// CreatedEvals is the set of evaluations created by the scheduler. The
	// reasons for this can be rolling-updates or blocked evals.
	CreatedEvals []*Evaluation

	// Diff contains the diff of the job and annotations on whether the change
	// causes an in-place update or create/destroy
	Diff *JobDiff

	// NextPeriodicLaunch is the time duration till the job would be launched if
	// submitted.
	NextPeriodicLaunch time.Time

	WriteMeta
}

// SingleAllocResponse is used to return a single allocation
type SingleAllocResponse struct {
	Alloc *Allocation
	QueryMeta
}

// AllocsGetResponse is used to return a set of allocations
type AllocsGetResponse struct {
	Allocs []*Allocation
	QueryMeta
}

// JobAllocationsResponse is used to return the allocations for a job
type JobAllocationsResponse struct {
	Allocations []*AllocListStub
	QueryMeta
}

// JobEvaluationsResponse is used to return the evaluations for a job
type JobEvaluationsResponse struct {
	Evaluations []*Evaluation
	QueryMeta
}

// SingleEvalResponse is used to return a single evaluation
type SingleEvalResponse struct {
	Eval *Evaluation
	QueryMeta
}

// EvalDequeueResponse is used to return from a dequeue
type EvalDequeueResponse struct {
	Eval  *Evaluation
	Token string
	QueryMeta
}

// PlanResponse is used to return from a PlanRequest
type PlanResponse struct {
	Result *PlanResult
	WriteMeta
}

// AllocListResponse is used for a list request
type AllocListResponse struct {
	Allocations []*AllocListStub
	QueryMeta
}

// EvalListResponse is used for a list request
type EvalListResponse struct {
	Evaluations []*Evaluation
	QueryMeta
}

// EvalAllocationsResponse is used to return the allocations for an evaluation
type EvalAllocationsResponse struct {
	Allocations []*AllocListStub
	QueryMeta
}

// PeriodicForceResponse is used to respond to a periodic job force launch
type PeriodicForceResponse struct {
	EvalID          string
	EvalCreateIndex uint64
	WriteMeta
}

const (
	NodeStatusInit  = "initializing"
	NodeStatusReady = "ready"
	NodeStatusDown  = "down"
)

// ShouldDrainNode checks if a given node status should trigger an
// evaluation. Some states don't require any further action.
func ShouldDrainNode(status string) bool {
	switch status {
	case NodeStatusInit, NodeStatusReady:
		return false
	case NodeStatusDown:
		return true
	default:
		panic(fmt.Sprintf("unhandled node status %s", status))
	}
}

// ValidNodeStatus is used to check if a node status is valid
func ValidNodeStatus(status string) bool {
	switch status {
	case NodeStatusInit, NodeStatusReady, NodeStatusDown:
		return true
	default:
		return false
	}
}

// Node is a representation of a schedulable client node
type Node struct {
	// ID is a unique identifier for the node. It can be constructed
	// by doing a concatenation of the Name and Datacenter as a simple
	// approach. Alternatively a UUID may be used.
	ID string

	// SecretID is an ID that is only known by the Node and the set of Servers.
	// It is not accessible via the API and is used to authenticate nodes
	// conducting priviledged activities.
	SecretID string

	// Datacenter for this node
	Datacenter string

	// Node name
	Name string

	// HTTPAddr is the address on which the Nomad client is listening for http
	// requests
	HTTPAddr string

	// Attributes is an arbitrary set of key/value
	// data that can be used for constraints. Examples
	// include "kernel.name=linux", "arch=386", "driver.docker=1",
	// "docker.runtime=1.8.3"
	Attributes map[string]string

	// Resources is the available resources on the client.
	// For example 'cpu=2' 'memory=2048'
	Resources *Resources

	// Reserved is the set of resources that are reserved,
	// and should be subtracted from the total resources for
	// the purposes of scheduling. This may be provide certain
	// high-watermark tolerances or because of external schedulers
	// consuming resources.
	Reserved *Resources

	// Links are used to 'link' this client to external
	// systems. For example 'consul=foo.dc1' 'aws=i-83212'
	// 'ami=ami-123'
	Links map[string]string

	// Meta is used to associate arbitrary metadata with this
	// client. This is opaque to Nomad.
	Meta map[string]string

	// NodeClass is an opaque identifier used to group nodes
	// together for the purpose of determining scheduling pressure.
	NodeClass string

	// ComputedClass is a unique id that identifies nodes with a common set of
	// attributes and capabilities.
	ComputedClass string

	// Drain is controlled by the servers, and not the client.
	// If true, no jobs will be scheduled to this node, and existing
	// allocations will be drained.
	Drain bool

	// Status of this node
	Status string

	// StatusDescription is meant to provide more human useful information
	StatusDescription string

	// StatusUpdatedAt is the time stamp at which the state of the node was
	// updated
	StatusUpdatedAt int64

	// Raft Indexes
	CreateIndex uint64
	ModifyIndex uint64
}

func (n *Node) Copy() *Node {
	if n == nil {
		return nil
	}
	nn := new(Node)
	*nn = *n
	nn.Attributes = CopyMapStringString(nn.Attributes)
	nn.Resources = nn.Resources.Copy()
	nn.Reserved = nn.Reserved.Copy()
	nn.Links = CopyMapStringString(nn.Links)
	nn.Meta = CopyMapStringString(nn.Meta)
	return nn
}

// TerminalStatus returns if the current status is terminal and
// will no longer transition.
func (n *Node) TerminalStatus() bool {
	switch n.Status {
	case NodeStatusDown:
		return true
	default:
		return false
	}
}

// Stub returns a summarized version of the node
func (n *Node) Stub() *NodeListStub {
	return &NodeListStub{
		ID:                n.ID,
		Datacenter:        n.Datacenter,
		Name:              n.Name,
		NodeClass:         n.NodeClass,
		Drain:             n.Drain,
		Status:            n.Status,
		StatusDescription: n.StatusDescription,
		CreateIndex:       n.CreateIndex,
		ModifyIndex:       n.ModifyIndex,
	}
}

// NodeListStub is used to return a subset of job information
// for the job list
type NodeListStub struct {
	ID                string
	Datacenter        string
	Name              string
	NodeClass         string
	Drain             bool
	Status            string
	StatusDescription string
	CreateIndex       uint64
	ModifyIndex       uint64
}

// Resources is used to define the resources available
// on a client
type Resources struct {
	CPU      int
	MemoryMB int `mapstructure:"memory"`
	DiskMB   int `mapstructure:"disk"`
	IOPS     int
	Networks []*NetworkResource
}

const (
	BytesInMegabyte = 1024 * 1024
)

// DefaultResources returns the default resources for a task.
func DefaultResources() *Resources {
	return &Resources{
		CPU:      100,
		MemoryMB: 10,
		IOPS:     0,
	}
}

// DiskInBytes returns the amount of disk resources in bytes.
func (r *Resources) DiskInBytes() int64 {
	return int64(r.DiskMB * BytesInMegabyte)
}

// Merge merges this resource with another resource.
func (r *Resources) Merge(other *Resources) {
	if other.CPU != 0 {
		r.CPU = other.CPU
	}
	if other.MemoryMB != 0 {
		r.MemoryMB = other.MemoryMB
	}
	if other.DiskMB != 0 {
		r.DiskMB = other.DiskMB
	}
	if other.IOPS != 0 {
		r.IOPS = other.IOPS
	}
	if len(other.Networks) != 0 {
		r.Networks = other.Networks
	}
}

func (r *Resources) Canonicalize() {
	// Ensure that an empty and nil slices are treated the same to avoid scheduling
	// problems since we use reflect DeepEquals.
	if len(r.Networks) == 0 {
		r.Networks = nil
	}

	for _, n := range r.Networks {
		n.Canonicalize()
	}
}

// MeetsMinResources returns an error if the resources specified are less than
// the minimum allowed.
func (r *Resources) MeetsMinResources() error {
	var mErr multierror.Error
	if r.CPU < 20 {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("minimum CPU value is 20; got %d", r.CPU))
	}
	if r.MemoryMB < 10 {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("minimum MemoryMB value is 10; got %d", r.MemoryMB))
	}
	if r.IOPS < 0 {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("minimum IOPS value is 0; got %d", r.IOPS))
	}
	for i, n := range r.Networks {
		if err := n.MeetsMinResources(); err != nil {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("network resource at index %d failed: %v", i, err))
		}
	}

	return mErr.ErrorOrNil()
}

// Copy returns a deep copy of the resources
func (r *Resources) Copy() *Resources {
	if r == nil {
		return nil
	}
	newR := new(Resources)
	*newR = *r
	if r.Networks != nil {
		n := len(r.Networks)
		newR.Networks = make([]*NetworkResource, n)
		for i := 0; i < n; i++ {
			newR.Networks[i] = r.Networks[i].Copy()
		}
	}
	return newR
}

// NetIndex finds the matching net index using device name
func (r *Resources) NetIndex(n *NetworkResource) int {
	for idx, net := range r.Networks {
		if net.Device == n.Device {
			return idx
		}
	}
	return -1
}

// Superset checks if one set of resources is a superset
// of another. This ignores network resources, and the NetworkIndex
// should be used for that.
func (r *Resources) Superset(other *Resources) (bool, string) {
	if r.CPU < other.CPU {
		return false, "cpu exhausted"
	}
	if r.MemoryMB < other.MemoryMB {
		return false, "memory exhausted"
	}
	if r.DiskMB < other.DiskMB {
		return false, "disk exhausted"
	}
	if r.IOPS < other.IOPS {
		return false, "iops exhausted"
	}
	return true, ""
}

// Add adds the resources of the delta to this, potentially
// returning an error if not possible.
func (r *Resources) Add(delta *Resources) error {
	if delta == nil {
		return nil
	}
	r.CPU += delta.CPU
	r.MemoryMB += delta.MemoryMB
	r.DiskMB += delta.DiskMB
	r.IOPS += delta.IOPS

	for _, n := range delta.Networks {
		// Find the matching interface by IP or CIDR
		idx := r.NetIndex(n)
		if idx == -1 {
			r.Networks = append(r.Networks, n.Copy())
		} else {
			r.Networks[idx].Add(n)
		}
	}
	return nil
}

func (r *Resources) GoString() string {
	return fmt.Sprintf("*%#v", *r)
}

type Port struct {
	Label string
	Value int `mapstructure:"static"`
}

// NetworkResource is used to represent available network
// resources
type NetworkResource struct {
	Device        string // Name of the device
	CIDR          string // CIDR block of addresses
	IP            string // IP address
	MBits         int    // Throughput
	ReservedPorts []Port // Reserved ports
	DynamicPorts  []Port // Dynamically assigned ports
}

func (n *NetworkResource) Canonicalize() {
	// Ensure that an empty and nil slices are treated the same to avoid scheduling
	// problems since we use reflect DeepEquals.
	if len(n.ReservedPorts) == 0 {
		n.ReservedPorts = nil
	}
	if len(n.DynamicPorts) == 0 {
		n.DynamicPorts = nil
	}
}

// MeetsMinResources returns an error if the resources specified are less than
// the minimum allowed.
func (n *NetworkResource) MeetsMinResources() error {
	var mErr multierror.Error
	if n.MBits < 1 {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("minimum MBits value is 1; got %d", n.MBits))
	}
	return mErr.ErrorOrNil()
}

// Copy returns a deep copy of the network resource
func (n *NetworkResource) Copy() *NetworkResource {
	if n == nil {
		return nil
	}
	newR := new(NetworkResource)
	*newR = *n
	if n.ReservedPorts != nil {
		newR.ReservedPorts = make([]Port, len(n.ReservedPorts))
		copy(newR.ReservedPorts, n.ReservedPorts)
	}
	if n.DynamicPorts != nil {
		newR.DynamicPorts = make([]Port, len(n.DynamicPorts))
		copy(newR.DynamicPorts, n.DynamicPorts)
	}
	return newR
}

// Add adds the resources of the delta to this, potentially
// returning an error if not possible.
func (n *NetworkResource) Add(delta *NetworkResource) {
	if len(delta.ReservedPorts) > 0 {
		n.ReservedPorts = append(n.ReservedPorts, delta.ReservedPorts...)
	}
	n.MBits += delta.MBits
	n.DynamicPorts = append(n.DynamicPorts, delta.DynamicPorts...)
}

func (n *NetworkResource) GoString() string {
	return fmt.Sprintf("*%#v", *n)
}

func (n *NetworkResource) MapLabelToValues(port_map map[string]int) map[string]int {
	labelValues := make(map[string]int)
	ports := append(n.ReservedPorts, n.DynamicPorts...)
	for _, port := range ports {
		if mapping, ok := port_map[port.Label]; ok {
			labelValues[port.Label] = mapping
		} else {
			labelValues[port.Label] = port.Value
		}
	}
	return labelValues
}

const (
	// JobTypeNomad is reserved for internal system tasks and is
	// always handled by the CoreScheduler.
	JobTypeCore    = "_core"
	JobTypeService = "service"
	JobTypeBatch   = "batch"
	JobTypeSystem  = "system"
)

const (
	JobStatusPending = "pending" // Pending means the job is waiting on scheduling
	JobStatusRunning = "running" // Running means the job has non-terminal allocations
	JobStatusDead    = "dead"    // Dead means all evaluation's and allocations are terminal
)

const (
	// JobMinPriority is the minimum allowed priority
	JobMinPriority = 1

	// JobDefaultPriority is the default priority if not
	// not specified.
	JobDefaultPriority = 50

	// JobMaxPriority is the maximum allowed priority
	JobMaxPriority = 100

	// Ensure CoreJobPriority is higher than any user
	// specified job so that it gets priority. This is important
	// for the system to remain healthy.
	CoreJobPriority = JobMaxPriority * 2
)

// JobSummary summarizes the state of the allocations of a job
type JobSummary struct {
	JobID   string
	Summary map[string]TaskGroupSummary

	// Raft Indexes
	CreateIndex uint64
	ModifyIndex uint64
}

// Copy returns a new copy of JobSummary
func (js *JobSummary) Copy() *JobSummary {
	newJobSummary := new(JobSummary)
	*newJobSummary = *js
	newTGSummary := make(map[string]TaskGroupSummary, len(js.Summary))
	for k, v := range js.Summary {
		newTGSummary[k] = v
	}
	newJobSummary.Summary = newTGSummary
	return newJobSummary
}

// TaskGroup summarizes the state of all the allocations of a particular
// TaskGroup
type TaskGroupSummary struct {
	Queued   int
	Complete int
	Failed   int
	Running  int
	Starting int
	Lost     int
}

// Job is the scope of a scheduling request to Nomad. It is the largest
// scoped object, and is a named collection of task groups. Each task group
// is further composed of tasks. A task group (TG) is the unit of scheduling
// however.
type Job struct {
	// Region is the Nomad region that handles scheduling this job
	Region string

	// ID is a unique identifier for the job per region. It can be
	// specified hierarchically like LineOfBiz/OrgName/Team/Project
	ID string

	// ParentID is the unique identifier of the job that spawned this job.
	ParentID string

	// Name is the logical name of the job used to refer to it. This is unique
	// per region, but not unique globally.
	Name string

	// Type is used to control various behaviors about the job. Most jobs
	// are service jobs, meaning they are expected to be long lived.
	// Some jobs are batch oriented meaning they run and then terminate.
	// This can be extended in the future to support custom schedulers.
	Type string

	// Priority is used to control scheduling importance and if this job
	// can preempt other jobs.
	Priority int

	// AllAtOnce is used to control if incremental scheduling of task groups
	// is allowed or if we must do a gang scheduling of the entire job. This
	// can slow down larger jobs if resources are not available.
	AllAtOnce bool `mapstructure:"all_at_once"`

	// Datacenters contains all the datacenters this job is allowed to span
	Datacenters []string

	// Constraints can be specified at a job level and apply to
	// all the task groups and tasks.
	Constraints []*Constraint

	// TaskGroups are the collections of task groups that this job needs
	// to run. Each task group is an atomic unit of scheduling and placement.
	TaskGroups []*TaskGroup

	// Update is used to control the update strategy
	Update UpdateStrategy

	// Periodic is used to define the interval the job is run at.
	Periodic *PeriodicConfig

	// Meta is used to associate arbitrary metadata with this
	// job. This is opaque to Nomad.
	Meta map[string]string

	// VaultToken is the Vault token that proves the submitter of the job has
	// access to the specified Vault policies. This field is only used to
	// transfer the token and is not stored after Job submission.
	VaultToken string `mapstructure:"vault_token"`

	// Job status
	Status string

	// StatusDescription is meant to provide more human useful information
	StatusDescription string

	// Raft Indexes
	CreateIndex    uint64
	ModifyIndex    uint64
	JobModifyIndex uint64
}

// Canonicalize is used to canonicalize fields in the Job. This should be called
// when registering a Job.
func (j *Job) Canonicalize() {
	// Ensure that an empty and nil map are treated the same to avoid scheduling
	// problems since we use reflect DeepEquals.
	if len(j.Meta) == 0 {
		j.Meta = nil
	}

	for _, tg := range j.TaskGroups {
		tg.Canonicalize(j)
	}
}

// Copy returns a deep copy of the Job. It is expected that callers use recover.
// This job can panic if the deep copy failed as it uses reflection.
func (j *Job) Copy() *Job {
	if j == nil {
		return nil
	}
	nj := new(Job)
	*nj = *j
	nj.Datacenters = CopySliceString(nj.Datacenters)
	nj.Constraints = CopySliceConstraints(nj.Constraints)

	if j.TaskGroups != nil {
		tgs := make([]*TaskGroup, len(nj.TaskGroups))
		for i, tg := range nj.TaskGroups {
			tgs[i] = tg.Copy()
		}
		nj.TaskGroups = tgs
	}

	nj.Periodic = nj.Periodic.Copy()
	nj.Meta = CopyMapStringString(nj.Meta)
	return nj
}

// Validate is used to sanity check a job input
func (j *Job) Validate() error {
	var mErr multierror.Error
	if j.Region == "" {
		mErr.Errors = append(mErr.Errors, errors.New("Missing job region"))
	}
	if j.ID == "" {
		mErr.Errors = append(mErr.Errors, errors.New("Missing job ID"))
	} else if strings.Contains(j.ID, " ") {
		mErr.Errors = append(mErr.Errors, errors.New("Job ID contains a space"))
	}
	if j.Name == "" {
		mErr.Errors = append(mErr.Errors, errors.New("Missing job name"))
	}
	if j.Type == "" {
		mErr.Errors = append(mErr.Errors, errors.New("Missing job type"))
	}
	if j.Priority < JobMinPriority || j.Priority > JobMaxPriority {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("Job priority must be between [%d, %d]", JobMinPriority, JobMaxPriority))
	}
	if len(j.Datacenters) == 0 {
		mErr.Errors = append(mErr.Errors, errors.New("Missing job datacenters"))
	}
	if len(j.TaskGroups) == 0 {
		mErr.Errors = append(mErr.Errors, errors.New("Missing job task groups"))
	}
	for idx, constr := range j.Constraints {
		if err := constr.Validate(); err != nil {
			outer := fmt.Errorf("Constraint %d validation failed: %s", idx+1, err)
			mErr.Errors = append(mErr.Errors, outer)
		}
	}

	// Check for duplicate task groups
	taskGroups := make(map[string]int)
	for idx, tg := range j.TaskGroups {
		if tg.Name == "" {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("Job task group %d missing name", idx+1))
		} else if existing, ok := taskGroups[tg.Name]; ok {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("Job task group %d redefines '%s' from group %d", idx+1, tg.Name, existing+1))
		} else {
			taskGroups[tg.Name] = idx
		}

		if j.Type == "system" && tg.Count > 1 {
			mErr.Errors = append(mErr.Errors,
				fmt.Errorf("Job task group %s has count %d. Count cannot exceed 1 with system scheduler",
					tg.Name, tg.Count))
		}
	}

	// Validate the task group
	for _, tg := range j.TaskGroups {
		if err := tg.Validate(); err != nil {
			outer := fmt.Errorf("Task group %s validation failed: %s", tg.Name, err)
			mErr.Errors = append(mErr.Errors, outer)
		}
	}

	// Validate periodic is only used with batch jobs.
	if j.IsPeriodic() && j.Periodic.Enabled {
		if j.Type != JobTypeBatch {
			mErr.Errors = append(mErr.Errors,
				fmt.Errorf("Periodic can only be used with %q scheduler", JobTypeBatch))
		}

		if err := j.Periodic.Validate(); err != nil {
			mErr.Errors = append(mErr.Errors, err)
		}
	}

	return mErr.ErrorOrNil()
}

// LookupTaskGroup finds a task group by name
func (j *Job) LookupTaskGroup(name string) *TaskGroup {
	for _, tg := range j.TaskGroups {
		if tg.Name == name {
			return tg
		}
	}
	return nil
}

// Stub is used to return a summary of the job
func (j *Job) Stub(summary *JobSummary) *JobListStub {
	return &JobListStub{
		ID:                j.ID,
		ParentID:          j.ParentID,
		Name:              j.Name,
		Type:              j.Type,
		Priority:          j.Priority,
		Status:            j.Status,
		StatusDescription: j.StatusDescription,
		CreateIndex:       j.CreateIndex,
		ModifyIndex:       j.ModifyIndex,
		JobModifyIndex:    j.JobModifyIndex,
		JobSummary:        summary,
	}
}

// IsPeriodic returns whether a job is periodic.
func (j *Job) IsPeriodic() bool {
	return j.Periodic != nil
}

// VaultPolicies returns the set of Vault policies per task group, per task
func (j *Job) VaultPolicies() map[string]map[string]*Vault {
	policies := make(map[string]map[string]*Vault, len(j.TaskGroups))

	for _, tg := range j.TaskGroups {
		tgPolicies := make(map[string]*Vault, len(tg.Tasks))
		policies[tg.Name] = tgPolicies

		for _, task := range tg.Tasks {
			if task.Vault == nil {
				continue
			}

			tgPolicies[task.Name] = task.Vault
		}
	}

	return policies
}

// JobListStub is used to return a subset of job information
// for the job list
type JobListStub struct {
	ID                string
	ParentID          string
	Name              string
	Type              string
	Priority          int
	Status            string
	StatusDescription string
	JobSummary        *JobSummary
	CreateIndex       uint64
	ModifyIndex       uint64
	JobModifyIndex    uint64
}

// UpdateStrategy is used to modify how updates are done
type UpdateStrategy struct {
	// Stagger is the amount of time between the updates
	Stagger time.Duration

	// MaxParallel is how many updates can be done in parallel
	MaxParallel int `mapstructure:"max_parallel"`
}

// Rolling returns if a rolling strategy should be used
func (u *UpdateStrategy) Rolling() bool {
	return u.Stagger > 0 && u.MaxParallel > 0
}

const (
	// PeriodicSpecCron is used for a cron spec.
	PeriodicSpecCron = "cron"

	// PeriodicSpecTest is only used by unit tests. It is a sorted, comma
	// separated list of unix timestamps at which to launch.
	PeriodicSpecTest = "_internal_test"
)

// Periodic defines the interval a job should be run at.
type PeriodicConfig struct {
	// Enabled determines if the job should be run periodically.
	Enabled bool

	// Spec specifies the interval the job should be run as. It is parsed based
	// on the SpecType.
	Spec string

	// SpecType defines the format of the spec.
	SpecType string

	// ProhibitOverlap enforces that spawned jobs do not run in parallel.
	ProhibitOverlap bool `mapstructure:"prohibit_overlap"`
}

func (p *PeriodicConfig) Copy() *PeriodicConfig {
	if p == nil {
		return nil
	}
	np := new(PeriodicConfig)
	*np = *p
	return np
}

func (p *PeriodicConfig) Validate() error {
	if !p.Enabled {
		return nil
	}

	if p.Spec == "" {
		return fmt.Errorf("Must specify a spec")
	}

	switch p.SpecType {
	case PeriodicSpecCron:
		// Validate the cron spec
		if _, err := cronexpr.Parse(p.Spec); err != nil {
			return fmt.Errorf("Invalid cron spec %q: %v", p.Spec, err)
		}
	case PeriodicSpecTest:
		// No-op
	default:
		return fmt.Errorf("Unknown periodic specification type %q", p.SpecType)
	}

	return nil
}

// Next returns the closest time instant matching the spec that is after the
// passed time. If no matching instance exists, the zero value of time.Time is
// returned. The `time.Location` of the returned value matches that of the
// passed time.
func (p *PeriodicConfig) Next(fromTime time.Time) time.Time {
	switch p.SpecType {
	case PeriodicSpecCron:
		if e, err := cronexpr.Parse(p.Spec); err == nil {
			return e.Next(fromTime)
		}
	case PeriodicSpecTest:
		split := strings.Split(p.Spec, ",")
		if len(split) == 1 && split[0] == "" {
			return time.Time{}
		}

		// Parse the times
		times := make([]time.Time, len(split))
		for i, s := range split {
			unix, err := strconv.Atoi(s)
			if err != nil {
				return time.Time{}
			}

			times[i] = time.Unix(int64(unix), 0)
		}

		// Find the next match
		for _, next := range times {
			if fromTime.Before(next) {
				return next
			}
		}
	}

	return time.Time{}
}

const (
	// PeriodicLaunchSuffix is the string appended to the periodic jobs ID
	// when launching derived instances of it.
	PeriodicLaunchSuffix = "/periodic-"
)

// PeriodicLaunch tracks the last launch time of a periodic job.
type PeriodicLaunch struct {
	ID     string    // ID of the periodic job.
	Launch time.Time // The last launch time.

	// Raft Indexes
	CreateIndex uint64
	ModifyIndex uint64
}

var (
	defaultServiceJobRestartPolicy = RestartPolicy{
		Delay:    15 * time.Second,
		Attempts: 2,
		Interval: 1 * time.Minute,
		Mode:     RestartPolicyModeDelay,
	}
	defaultBatchJobRestartPolicy = RestartPolicy{
		Delay:    15 * time.Second,
		Attempts: 15,
		Interval: 7 * 24 * time.Hour,
		Mode:     RestartPolicyModeDelay,
	}
)

const (
	// RestartPolicyModeDelay causes an artificial delay till the next interval is
	// reached when the specified attempts have been reached in the interval.
	RestartPolicyModeDelay = "delay"

	// RestartPolicyModeFail causes a job to fail if the specified number of
	// attempts are reached within an interval.
	RestartPolicyModeFail = "fail"
)

// RestartPolicy configures how Tasks are restarted when they crash or fail.
type RestartPolicy struct {
	// Attempts is the number of restart that will occur in an interval.
	Attempts int

	// Interval is a duration in which we can limit the number of restarts
	// within.
	Interval time.Duration

	// Delay is the time between a failure and a restart.
	Delay time.Duration

	// Mode controls what happens when the task restarts more than attempt times
	// in an interval.
	Mode string
}

func (r *RestartPolicy) Copy() *RestartPolicy {
	if r == nil {
		return nil
	}
	nrp := new(RestartPolicy)
	*nrp = *r
	return nrp
}

func (r *RestartPolicy) Validate() error {
	switch r.Mode {
	case RestartPolicyModeDelay, RestartPolicyModeFail:
	default:
		return fmt.Errorf("Unsupported restart mode: %q", r.Mode)
	}

	// Check for ambiguous/confusing settings
	if r.Attempts == 0 && r.Mode != RestartPolicyModeFail {
		return fmt.Errorf("Restart policy %q with %d attempts is ambiguous", r.Mode, r.Attempts)
	}

	if r.Interval == 0 {
		return nil
	}
	if time.Duration(r.Attempts)*r.Delay > r.Interval {
		return fmt.Errorf("Nomad can't restart the TaskGroup %v times in an interval of %v with a delay of %v", r.Attempts, r.Interval, r.Delay)
	}
	return nil
}

func NewRestartPolicy(jobType string) *RestartPolicy {
	switch jobType {
	case JobTypeService, JobTypeSystem:
		rp := defaultServiceJobRestartPolicy
		return &rp
	case JobTypeBatch:
		rp := defaultBatchJobRestartPolicy
		return &rp
	}
	return nil
}

// TaskGroup is an atomic unit of placement. Each task group belongs to
// a job and may contain any number of tasks. A task group support running
// in many replicas using the same configuration..
type TaskGroup struct {
	// Name of the task group
	Name string

	// Count is the number of replicas of this task group that should
	// be scheduled.
	Count int

	// Constraints can be specified at a task group level and apply to
	// all the tasks contained.
	Constraints []*Constraint

	//RestartPolicy of a TaskGroup
	RestartPolicy *RestartPolicy

	// Tasks are the collection of tasks that this task group needs to run
	Tasks []*Task

	// EphemeralDisk is the disk resources that the task group requests
	EphemeralDisk *EphemeralDisk

	// Meta is used to associate arbitrary metadata with this
	// task group. This is opaque to Nomad.
	Meta map[string]string
}

func (tg *TaskGroup) Copy() *TaskGroup {
	if tg == nil {
		return nil
	}
	ntg := new(TaskGroup)
	*ntg = *tg
	ntg.Constraints = CopySliceConstraints(ntg.Constraints)

	ntg.RestartPolicy = ntg.RestartPolicy.Copy()

	if tg.Tasks != nil {
		tasks := make([]*Task, len(ntg.Tasks))
		for i, t := range ntg.Tasks {
			tasks[i] = t.Copy()
		}
		ntg.Tasks = tasks
	}

	ntg.Meta = CopyMapStringString(ntg.Meta)

	if tg.EphemeralDisk != nil {
		ntg.EphemeralDisk = tg.EphemeralDisk.Copy()
	}
	return ntg
}

// Canonicalize is used to canonicalize fields in the TaskGroup.
func (tg *TaskGroup) Canonicalize(job *Job) {
	// Ensure that an empty and nil map are treated the same to avoid scheduling
	// problems since we use reflect DeepEquals.
	if len(tg.Meta) == 0 {
		tg.Meta = nil
	}

	// Set the default restart policy.
	if tg.RestartPolicy == nil {
		tg.RestartPolicy = NewRestartPolicy(job.Type)
	}

	for _, task := range tg.Tasks {
		task.Canonicalize(job, tg)
	}
}

// Validate is used to sanity check a task group
func (tg *TaskGroup) Validate() error {
	var mErr multierror.Error
	if tg.Name == "" {
		mErr.Errors = append(mErr.Errors, errors.New("Missing task group name"))
	}
	if tg.Count < 0 {
		mErr.Errors = append(mErr.Errors, errors.New("Task group count can't be negative"))
	}
	if len(tg.Tasks) == 0 {
		mErr.Errors = append(mErr.Errors, errors.New("Missing tasks for task group"))
	}
	for idx, constr := range tg.Constraints {
		if err := constr.Validate(); err != nil {
			outer := fmt.Errorf("Constraint %d validation failed: %s", idx+1, err)
			mErr.Errors = append(mErr.Errors, outer)
		}
	}

	if tg.RestartPolicy != nil {
		if err := tg.RestartPolicy.Validate(); err != nil {
			mErr.Errors = append(mErr.Errors, err)
		}
	} else {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("Task Group %v should have a restart policy", tg.Name))
	}

	if tg.EphemeralDisk != nil {
		if err := tg.EphemeralDisk.Validate(); err != nil {
			mErr.Errors = append(mErr.Errors, err)
		}
	} else {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("Task Group %v should have a local disk object", tg.Name))
	}

	// Check for duplicate tasks
	tasks := make(map[string]int)
	for idx, task := range tg.Tasks {
		if task.Name == "" {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("Task %d missing name", idx+1))
		} else if existing, ok := tasks[task.Name]; ok {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("Task %d redefines '%s' from task %d", idx+1, task.Name, existing+1))
		} else {
			tasks[task.Name] = idx
		}
	}

	// Validate the tasks
	for _, task := range tg.Tasks {
		if err := task.Validate(tg.EphemeralDisk); err != nil {
			outer := fmt.Errorf("Task %s validation failed: %s", task.Name, err)
			mErr.Errors = append(mErr.Errors, outer)
		}
	}
	return mErr.ErrorOrNil()
}

// LookupTask finds a task by name
func (tg *TaskGroup) LookupTask(name string) *Task {
	for _, t := range tg.Tasks {
		if t.Name == name {
			return t
		}
	}
	return nil
}

func (tg *TaskGroup) GoString() string {
	return fmt.Sprintf("*%#v", *tg)
}

const (
	// TODO add Consul TTL check
	ServiceCheckHTTP   = "http"
	ServiceCheckTCP    = "tcp"
	ServiceCheckScript = "script"

	// minCheckInterval is the minimum check interval permitted.  Consul
	// currently has its MinInterval set to 1s.  Mirror that here for
	// consistency.
	minCheckInterval = 1 * time.Second

	// minCheckTimeout is the minimum check timeout permitted for Consul
	// script TTL checks.
	minCheckTimeout = 1 * time.Second
)

// The ServiceCheck data model represents the consul health check that
// Nomad registers for a Task
type ServiceCheck struct {
	Name          string        // Name of the check, defaults to id
	Type          string        // Type of the check - tcp, http, docker and script
	Command       string        // Command is the command to run for script checks
	Args          []string      // Args is a list of argumes for script checks
	Path          string        // path of the health check url for http type check
	Protocol      string        // Protocol to use if check is http, defaults to http
	PortLabel     string        `mapstructure:"port"` // The port to use for tcp/http checks
	Interval      time.Duration // Interval of the check
	Timeout       time.Duration // Timeout of the response from the check before consul fails the check
	InitialStatus string        `mapstructure:"initial_status"` // Initial status of the check
}

func (sc *ServiceCheck) Copy() *ServiceCheck {
	if sc == nil {
		return nil
	}
	nsc := new(ServiceCheck)
	*nsc = *sc
	return nsc
}

func (sc *ServiceCheck) Canonicalize(serviceName string) {
	// Ensure empty slices are treated as null to avoid scheduling issues when
	// using DeepEquals.
	if len(sc.Args) == 0 {
		sc.Args = nil
	}

	if sc.Name == "" {
		sc.Name = fmt.Sprintf("service: %q check", serviceName)
	}
}

// validate a Service's ServiceCheck
func (sc *ServiceCheck) validate() error {
	switch strings.ToLower(sc.Type) {
	case ServiceCheckTCP:
		if sc.Timeout < minCheckTimeout {
			return fmt.Errorf("timeout (%v) is lower than required minimum timeout %v", sc.Timeout, minCheckInterval)
		}
	case ServiceCheckHTTP:
		if sc.Path == "" {
			return fmt.Errorf("http type must have a valid http path")
		}

		if sc.Timeout < minCheckTimeout {
			return fmt.Errorf("timeout (%v) is lower than required minimum timeout %v", sc.Timeout, minCheckInterval)
		}
	case ServiceCheckScript:
		if sc.Command == "" {
			return fmt.Errorf("script type must have a valid script path")
		}

		// TODO: enforce timeout on the Client side and reenable
		// validation.
	default:
		return fmt.Errorf(`invalid type (%+q), must be one of "http", "tcp", or "script" type`, sc.Type)
	}

	if sc.Interval < minCheckInterval {
		return fmt.Errorf("interval (%v) can not be lower than %v", sc.Interval, minCheckInterval)
	}

	switch sc.InitialStatus {
	case "":
	case api.HealthUnknown:
	case api.HealthPassing:
	case api.HealthWarning:
	case api.HealthCritical:
	default:
		return fmt.Errorf(`invalid initial check state (%s), must be one of %q, %q, %q, %q or empty`, sc.InitialStatus, api.HealthUnknown, api.HealthPassing, api.HealthWarning, api.HealthCritical)

	}

	return nil
}

// RequiresPort returns whether the service check requires the task has a port.
func (sc *ServiceCheck) RequiresPort() bool {
	switch sc.Type {
	case ServiceCheckHTTP, ServiceCheckTCP:
		return true
	default:
		return false
	}
}

func (sc *ServiceCheck) Hash(serviceID string) string {
	h := sha1.New()
	io.WriteString(h, serviceID)
	io.WriteString(h, sc.Name)
	io.WriteString(h, sc.Type)
	io.WriteString(h, sc.Command)
	io.WriteString(h, strings.Join(sc.Args, ""))
	io.WriteString(h, sc.Path)
	io.WriteString(h, sc.Protocol)
	io.WriteString(h, sc.PortLabel)
	io.WriteString(h, sc.Interval.String())
	io.WriteString(h, sc.Timeout.String())
	return fmt.Sprintf("%x", h.Sum(nil))
}

// Service represents a Consul service definition in Nomad
type Service struct {
	// Name of the service registered with Consul. Consul defaults the
	// Name to ServiceID if not specified.  The Name if specified is used
	// as one of the seed values when generating a Consul ServiceID.
	Name string

	// PortLabel is either the numeric port number or the `host:port`.
	// To specify the port number using the host's Consul Advertise
	// address, specify an empty host in the PortLabel (e.g. `:port`).
	PortLabel string          `mapstructure:"port"`
	Tags      []string        // List of tags for the service
	Checks    []*ServiceCheck // List of checks associated with the service
}

func (s *Service) Copy() *Service {
	if s == nil {
		return nil
	}
	ns := new(Service)
	*ns = *s
	ns.Tags = CopySliceString(ns.Tags)

	if s.Checks != nil {
		checks := make([]*ServiceCheck, len(ns.Checks))
		for i, c := range ns.Checks {
			checks[i] = c.Copy()
		}
		ns.Checks = checks
	}

	return ns
}

// Canonicalize interpolates values of Job, Task Group and Task in the Service
// Name. This also generates check names, service id and check ids.
func (s *Service) Canonicalize(job string, taskGroup string, task string) {
	// Ensure empty lists are treated as null to avoid scheduler issues when
	// using DeepEquals
	if len(s.Tags) == 0 {
		s.Tags = nil
	}
	if len(s.Checks) == 0 {
		s.Checks = nil
	}

	s.Name = args.ReplaceEnv(s.Name, map[string]string{
		"JOB":       job,
		"TASKGROUP": taskGroup,
		"TASK":      task,
		"BASE":      fmt.Sprintf("%s-%s-%s", job, taskGroup, task),
	},
	)

	for _, check := range s.Checks {
		check.Canonicalize(s.Name)
	}
}

// Validate checks if the Check definition is valid
func (s *Service) Validate() error {
	var mErr multierror.Error

	// Ensure the service name is valid per RFC-952 §1
	// (https://tools.ietf.org/html/rfc952), RFC-1123 §2.1
	// (https://tools.ietf.org/html/rfc1123), and RFC-2782
	// (https://tools.ietf.org/html/rfc2782).
	re := regexp.MustCompile(`^(?i:[a-z0-9]|[a-z0-9][a-z0-9\-]{0,61}[a-z0-9])$`)
	if !re.MatchString(s.Name) {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("service name must be valid per RFC 1123 and can contain only alphanumeric characters or dashes and must be less than 63 characters long: %q", s.Name))
	}

	for _, c := range s.Checks {
		if s.PortLabel == "" && c.RequiresPort() {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("check %s invalid: check requires a port but the service %+q has no port", c.Name, s.Name))
			continue
		}

		if err := c.validate(); err != nil {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("check %s invalid: %v", c.Name, err))
		}
	}
	return mErr.ErrorOrNil()
}

// Hash calculates the hash of the check based on it's content and the service
// which owns it
func (s *Service) Hash() string {
	h := sha1.New()
	io.WriteString(h, s.Name)
	io.WriteString(h, strings.Join(s.Tags, ""))
	io.WriteString(h, s.PortLabel)
	return fmt.Sprintf("%x", h.Sum(nil))
}

const (
	// DefaultKillTimeout is the default timeout between signaling a task it
	// will be killed and killing it.
	DefaultKillTimeout = 5 * time.Second
)

// LogConfig provides configuration for log rotation
type LogConfig struct {
	MaxFiles         int `mapstructure:"max_files"`
	MaxFileSizeMB    int `mapstructure:"max_file_size"`
	LogShuttleConfig *LogShuttleConfig
}

// LogShuttleConfig configures log-shuttle log delivery
type LogShuttleConfig struct {
	UseGzip       bool
	Drop          bool
	Prival        string
	Version       string
	Procid        string
	Appname       string
	LogplexToken  string
	Hostname      string
	Msgid         string
	LogsURL       string
	StatsSource   string
	StatsInterval time.Duration
	WaitDuration  time.Duration
	Timeout       time.Duration
	MaxAttempts   int
	NumOutlets    int
	BatchSize     int
	BackBuff      int
	MaxLineLength int
	KinesisShards int
}

// DefaultLogConfig returns the default LogConfig values.
func DefaultLogConfig() *LogConfig {
	return &LogConfig{
		MaxFiles:      10,
		MaxFileSizeMB: 10,
	}
}

// Validate returns an error if the log config specified are less than
// the minimum allowed.
func (l *LogConfig) Validate() error {
	var mErr multierror.Error
	if l.MaxFiles < 1 {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("minimum number of files is 1; got %d", l.MaxFiles))
	}
	if l.MaxFileSizeMB < 1 {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("minimum file size is 1MB; got %d", l.MaxFileSizeMB))
	}
	return mErr.ErrorOrNil()
}

// Task is a single process typically that is executed as part of a task group.
type Task struct {
	// Name of the task
	Name string

	// Driver is used to control which driver is used
	Driver string

	// User is used to determine which user will run the task. It defaults to
	// the same user the Nomad client is being run as.
	User string

	// Config is provided to the driver to initialize
	Config map[string]interface{}

	// Map of environment variables to be used by the driver
	Env map[string]string

	// Only use explicitly set Env variables in task environment
	ExcludeNomadEnv bool

	// List of service definitions exposed by the Task
	Services []*Service

	// Vault is used to define the set of Vault policies that this task should
	// have access to.
	Vault *Vault

	// Constraints can be specified at a task level and apply only to
	// the particular task.
	Constraints []*Constraint

	// Resources is the resources needed by this task
	Resources *Resources

	// Meta is used to associate arbitrary metadata with this
	// task. This is opaque to Nomad.
	Meta map[string]string

	// KillTimeout is the time between signaling a task that it will be
	// killed and killing it.
	KillTimeout time.Duration `mapstructure:"kill_timeout"`

	// LogConfig provides configuration for log rotation
	LogConfig *LogConfig `mapstructure:"logs"`

	// Artifacts is a list of artifacts to download and extract before running
	// the task.
	Artifacts []*TaskArtifact
}

func (t *Task) Copy() *Task {
	if t == nil {
		return nil
	}
	nt := new(Task)
	*nt = *t
	nt.Env = CopyMapStringString(nt.Env)

	if t.Services != nil {
		services := make([]*Service, len(nt.Services))
		for i, s := range nt.Services {
			services[i] = s.Copy()
		}
		nt.Services = services
	}

	nt.Constraints = CopySliceConstraints(nt.Constraints)

	nt.Vault = nt.Vault.Copy()
	nt.Resources = nt.Resources.Copy()
	nt.Meta = CopyMapStringString(nt.Meta)

	if t.Artifacts != nil {
		artifacts := make([]*TaskArtifact, 0, len(t.Artifacts))
		for _, a := range nt.Artifacts {
			artifacts = append(artifacts, a.Copy())
		}
		nt.Artifacts = artifacts
	}

	if i, err := copystructure.Copy(nt.Config); err != nil {
		nt.Config = i.(map[string]interface{})
	}

	return nt
}

// Canonicalize canonicalizes fields in the task.
func (t *Task) Canonicalize(job *Job, tg *TaskGroup) {
	// Ensure that an empty and nil map are treated the same to avoid scheduling
	// problems since we use reflect DeepEquals.
	if len(t.Meta) == 0 {
		t.Meta = nil
	}
	if len(t.Config) == 0 {
		t.Config = nil
	}
	if len(t.Env) == 0 {
		t.Env = nil
	}

	for _, service := range t.Services {
		service.Canonicalize(job.Name, tg.Name, t.Name)
	}

	if t.Resources != nil {
		t.Resources.Canonicalize()
	}

	// Set the default timeout if it is not specified.
	if t.KillTimeout == 0 {
		t.KillTimeout = DefaultKillTimeout
	}
}

func (t *Task) GoString() string {
	return fmt.Sprintf("*%#v", *t)
}

func (t *Task) FindHostAndPortFor(portLabel string) (string, int) {
	for _, network := range t.Resources.Networks {
		if p, ok := network.MapLabelToValues(nil)[portLabel]; ok {
			return network.IP, p
		}
	}
	return "", 0
}

// Validate is used to sanity check a task
func (t *Task) Validate(ephemeralDisk *EphemeralDisk) error {
	var mErr multierror.Error
	if t.Name == "" {
		mErr.Errors = append(mErr.Errors, errors.New("Missing task name"))
	}
	if strings.ContainsAny(t.Name, `/\`) {
		// We enforce this so that when creating the directory on disk it will
		// not have any slashes.
		mErr.Errors = append(mErr.Errors, errors.New("Task name can not include slashes"))
	}
	if t.Driver == "" {
		mErr.Errors = append(mErr.Errors, errors.New("Missing task driver"))
	}
	if t.KillTimeout.Nanoseconds() < 0 {
		mErr.Errors = append(mErr.Errors, errors.New("KillTimeout must be a positive value"))
	}

	// Validate the resources.
	if t.Resources == nil {
		mErr.Errors = append(mErr.Errors, errors.New("Missing task resources"))
	} else if err := t.Resources.MeetsMinResources(); err != nil {
		mErr.Errors = append(mErr.Errors, err)
	}

	// Ensure the task isn't asking for disk resources
	if t.Resources != nil {
		if t.Resources.DiskMB > 0 {
			mErr.Errors = append(mErr.Errors, errors.New("Task can't ask for disk resources, they have to be specified at the task group level."))
		}
	}

	// Validate the log config
	if t.LogConfig == nil {
		mErr.Errors = append(mErr.Errors, errors.New("Missing Log Config"))
	} else if err := t.LogConfig.Validate(); err != nil {
		mErr.Errors = append(mErr.Errors, err)
	}

	for idx, constr := range t.Constraints {
		if err := constr.Validate(); err != nil {
			outer := fmt.Errorf("Constraint %d validation failed: %s", idx+1, err)
			mErr.Errors = append(mErr.Errors, outer)
		}
	}

	// Validate Services
	if err := validateServices(t); err != nil {
		mErr.Errors = append(mErr.Errors, err)
	}

	if t.LogConfig != nil && ephemeralDisk != nil {
		logUsage := (t.LogConfig.MaxFiles * t.LogConfig.MaxFileSizeMB)
		if ephemeralDisk.SizeMB <= logUsage {
			mErr.Errors = append(mErr.Errors,
				fmt.Errorf("log storage (%d MB) must be less than requested disk capacity (%d MB)",
					logUsage, ephemeralDisk.SizeMB))
		}
	}

	for idx, artifact := range t.Artifacts {
		if err := artifact.Validate(); err != nil {
			outer := fmt.Errorf("Artifact %d validation failed: %v", idx+1, err)
			mErr.Errors = append(mErr.Errors, outer)
		}
	}

	if t.Vault != nil {
		if err := t.Vault.Validate(); err != nil {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("Vault validation failed: %v", err))
		}
	}

	return mErr.ErrorOrNil()
}

// validateServices takes a task and validates the services within it are valid
// and reference ports that exist.
func validateServices(t *Task) error {
	var mErr multierror.Error

	// Ensure that services don't ask for non-existent ports and their names are
	// unique.
	servicePorts := make(map[string][]string)
	knownServices := make(map[string]struct{})
	for i, service := range t.Services {
		if err := service.Validate(); err != nil {
			outer := fmt.Errorf("service[%d] %+q validation failed: %s", i, service.Name, err)
			mErr.Errors = append(mErr.Errors, outer)
		}
		if _, ok := knownServices[service.Name]; ok {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("service %q is duplicate", service.Name))
		}
		knownServices[service.Name] = struct{}{}

		if service.PortLabel != "" {
			servicePorts[service.PortLabel] = append(servicePorts[service.PortLabel], service.Name)
		}

		// Ensure that check names are unique.
		knownChecks := make(map[string]struct{})
		for _, check := range service.Checks {
			if _, ok := knownChecks[check.Name]; ok {
				mErr.Errors = append(mErr.Errors, fmt.Errorf("check %q is duplicate", check.Name))
			}
			knownChecks[check.Name] = struct{}{}
		}
	}

	// Get the set of port labels.
	portLabels := make(map[string]struct{})
	if t.Resources != nil {
		for _, network := range t.Resources.Networks {
			ports := network.MapLabelToValues(nil)
			for portLabel, _ := range ports {
				portLabels[portLabel] = struct{}{}
			}
		}
	}

	// Ensure all ports referenced in services exist.
	for servicePort, services := range servicePorts {
		_, ok := portLabels[servicePort]
		if !ok {
			joined := strings.Join(services, ", ")
			err := fmt.Errorf("port label %q referenced by services %v does not exist", servicePort, joined)
			mErr.Errors = append(mErr.Errors, err)
		}
	}
	return mErr.ErrorOrNil()
}

// Set of possible states for a task.
const (
	TaskStatePending = "pending" // The task is waiting to be run.
	TaskStateRunning = "running" // The task is currently running.
	TaskStateDead    = "dead"    // Terminal state of task.
)

// TaskState tracks the current state of a task and events that caused state
// transitions.
type TaskState struct {
	// The current state of the task.
	State string

	// Series of task events that transition the state of the task.
	Events []*TaskEvent
}

func (ts *TaskState) Copy() *TaskState {
	if ts == nil {
		return nil
	}
	copy := new(TaskState)
	copy.State = ts.State

	if ts.Events != nil {
		copy.Events = make([]*TaskEvent, len(ts.Events))
		for i, e := range ts.Events {
			copy.Events[i] = e.Copy()
		}
	}
	return copy
}

// Failed returns true if the task has has failed.
func (ts *TaskState) Failed() bool {
	l := len(ts.Events)
	if ts.State != TaskStateDead || l == 0 {
		return false
	}

	switch ts.Events[l-1].Type {
	case TaskDiskExceeded, TaskNotRestarting, TaskArtifactDownloadFailed, TaskFailedValidation:
		return true
	default:
		return false
	}
}

// Successful returns whether a task finished successfully.
func (ts *TaskState) Successful() bool {
	l := len(ts.Events)
	if ts.State != TaskStateDead || l == 0 {
		return false
	}

	e := ts.Events[l-1]
	if e.Type != TaskTerminated {
		return false
	}

	return e.ExitCode == 0
}

const (
	// TaskDriveFailure indicates that the task could not be started due to a
	// failure in the driver.
	TaskDriverFailure = "Driver Failure"

	// TaskReceived signals that the task has been pulled by the client at the
	// given timestamp.
	TaskReceived = "Received"

	// TaskFailedValidation indicates the task was invalid and as such was not
	// run.
	TaskFailedValidation = "Failed Validation"

	// TaskStarted signals that the task was started and its timestamp can be
	// used to determine the running length of the task.
	TaskStarted = "Started"

	// TaskTerminated indicates that the task was started and exited.
	TaskTerminated = "Terminated"

	// TaskKilling indicates a kill signal has been sent to the task.
	TaskKilling = "Killing"

	// TaskKilled indicates a user has killed the task.
	TaskKilled = "Killed"

	// TaskRestarting indicates that task terminated and is being restarted.
	TaskRestarting = "Restarting"

	// TaskNotRestarting indicates that the task has failed and is not being
	// restarted because it has exceeded its restart policy.
	TaskNotRestarting = "Not Restarting"

	// TaskDownloadingArtifacts means the task is downloading the artifacts
	// specified in the task.
	TaskDownloadingArtifacts = "Downloading Artifacts"

	// TaskArtifactDownloadFailed indicates that downloading the artifacts
	// failed.
	TaskArtifactDownloadFailed = "Failed Artifact Download"

	// TaskDiskExceeded indicates that one of the tasks in a taskgroup has
	// exceeded the requested disk resources.
	TaskDiskExceeded = "Disk Resources Exceeded"

	// TaskSiblingFailed indicates that a sibling task in the task group has
	// failed.
	TaskSiblingFailed = "Sibling task failed"
)

// TaskEvent is an event that effects the state of a task and contains meta-data
// appropriate to the events type.
type TaskEvent struct {
	Type string
	Time int64 // Unix Nanosecond timestamp

	// Restart fields.
	RestartReason string

	// Driver Failure fields.
	DriverError string // A driver error occurred while starting the task.

	// Task Terminated Fields.
	ExitCode int    // The exit code of the task.
	Signal   int    // The signal that terminated the task.
	Message  string // A possible message explaining the termination of the task.

	// Killing fields
	KillTimeout time.Duration

	// Task Killed Fields.
	KillError string // Error killing the task.

	// TaskRestarting fields.
	StartDelay int64 // The sleep period before restarting the task in unix nanoseconds.

	// Artifact Download fields
	DownloadError string // Error downloading artifacts

	// Validation fields
	ValidationError string // Validation error

	// The maximum allowed task disk size.
	DiskLimit int64

	// The recorded task disk size.
	DiskSize int64

	// Name of the sibling task that caused termination of the task that
	// the TaskEvent refers to.
	FailedSibling string
}

func (te *TaskEvent) GoString() string {
	return fmt.Sprintf("%v at %v", te.Type, te.Time)
}

func (te *TaskEvent) Copy() *TaskEvent {
	if te == nil {
		return nil
	}
	copy := new(TaskEvent)
	*copy = *te
	return copy
}

func NewTaskEvent(event string) *TaskEvent {
	return &TaskEvent{
		Type: event,
		Time: time.Now().UnixNano(),
	}
}

func (e *TaskEvent) SetDriverError(err error) *TaskEvent {
	if err != nil {
		e.DriverError = err.Error()
	}
	return e
}

func (e *TaskEvent) SetExitCode(c int) *TaskEvent {
	e.ExitCode = c
	return e
}

func (e *TaskEvent) SetSignal(s int) *TaskEvent {
	e.Signal = s
	return e
}

func (e *TaskEvent) SetExitMessage(err error) *TaskEvent {
	if err != nil {
		e.Message = err.Error()
	}
	return e
}

func (e *TaskEvent) SetKillError(err error) *TaskEvent {
	if err != nil {
		e.KillError = err.Error()
	}
	return e
}

func (e *TaskEvent) SetRestartDelay(delay time.Duration) *TaskEvent {
	e.StartDelay = int64(delay)
	return e
}

func (e *TaskEvent) SetRestartReason(reason string) *TaskEvent {
	e.RestartReason = reason
	return e
}

func (e *TaskEvent) SetDownloadError(err error) *TaskEvent {
	if err != nil {
		e.DownloadError = err.Error()
	}
	return e
}

func (e *TaskEvent) SetValidationError(err error) *TaskEvent {
	if err != nil {
		e.ValidationError = err.Error()
	}
	return e
}

func (e *TaskEvent) SetKillTimeout(timeout time.Duration) *TaskEvent {
	e.KillTimeout = timeout
	return e
}

func (e *TaskEvent) SetDiskLimit(limit int64) *TaskEvent {
	e.DiskLimit = limit
	return e
}

func (e *TaskEvent) SetDiskSize(size int64) *TaskEvent {
	e.DiskSize = size
	return e
}

func (e *TaskEvent) SetFailedSibling(sibling string) *TaskEvent {
	e.FailedSibling = sibling
	return e
}

// TaskArtifact is an artifact to download before running the task.
type TaskArtifact struct {
	// GetterSource is the source to download an artifact using go-getter
	GetterSource string `mapstructure:"source"`

	// GetterOptions are options to use when downloading the artifact using
	// go-getter.
	GetterOptions map[string]string `mapstructure:"options"`

	// RelativeDest is the download destination given relative to the task's
	// directory.
	RelativeDest string `mapstructure:"destination"`
}

func (ta *TaskArtifact) Copy() *TaskArtifact {
	if ta == nil {
		return nil
	}
	nta := new(TaskArtifact)
	*nta = *ta
	nta.GetterOptions = CopyMapStringString(ta.GetterOptions)
	return nta
}

func (ta *TaskArtifact) GoString() string {
	return fmt.Sprintf("%+v", ta)
}

func (ta *TaskArtifact) Validate() error {
	// Verify the source
	var mErr multierror.Error
	if ta.GetterSource == "" {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("source must be specified"))
	}

	// Verify the destination doesn't escape the tasks directory
	alloc, err := filepath.Abs(filepath.Join("/", "foo/", "bar/"))
	if err != nil {
		mErr.Errors = append(mErr.Errors, err)
		return mErr.ErrorOrNil()
	}
	abs, err := filepath.Abs(filepath.Join(alloc, ta.RelativeDest))
	if err != nil {
		mErr.Errors = append(mErr.Errors, err)
		return mErr.ErrorOrNil()
	}
	rel, err := filepath.Rel(alloc, abs)
	if err != nil {
		mErr.Errors = append(mErr.Errors, err)
		return mErr.ErrorOrNil()
	}
	if strings.HasPrefix(rel, "..") {
		mErr.Errors = append(mErr.Errors, fmt.Errorf("destination escapes task's directory"))
	}

	// Verify the checksum
	if check, ok := ta.GetterOptions["checksum"]; ok {
		check = strings.TrimSpace(check)
		if check == "" {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("checksum value can not be empty"))
			return mErr.ErrorOrNil()
		}

		parts := strings.Split(check, ":")
		if l := len(parts); l != 2 {
			mErr.Errors = append(mErr.Errors, fmt.Errorf(`checksum must be given as "type:value"; got %q`, check))
			return mErr.ErrorOrNil()
		}

		checksumVal := parts[1]
		checksumBytes, err := hex.DecodeString(checksumVal)
		if err != nil {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("invalid checksum: %v", err))
			return mErr.ErrorOrNil()
		}

		checksumType := parts[0]
		expectedLength := 0
		switch checksumType {
		case "md5":
			expectedLength = md5.Size
		case "sha1":
			expectedLength = sha1.Size
		case "sha256":
			expectedLength = sha256.Size
		case "sha512":
			expectedLength = sha512.Size
		default:
			mErr.Errors = append(mErr.Errors, fmt.Errorf("unsupported checksum type: %s", checksumType))
			return mErr.ErrorOrNil()
		}

		if len(checksumBytes) != expectedLength {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("invalid %s checksum: %v", checksumType, checksumVal))
			return mErr.ErrorOrNil()
		}
	}

	return mErr.ErrorOrNil()
}

const (
	ConstraintDistinctHosts = "distinct_hosts"
	ConstraintRegex         = "regexp"
	ConstraintVersion       = "version"
)

// Constraints are used to restrict placement options.
type Constraint struct {
	LTarget string // Left-hand target
	RTarget string // Right-hand target
	Operand string // Constraint operand (<=, <, =, !=, >, >=), contains, near
	str     string // Memoized string
}

func (c *Constraint) Copy() *Constraint {
	if c == nil {
		return nil
	}
	nc := new(Constraint)
	*nc = *c
	return nc
}

func (c *Constraint) String() string {
	if c.str != "" {
		return c.str
	}
	c.str = fmt.Sprintf("%s %s %s", c.LTarget, c.Operand, c.RTarget)
	return c.str
}

func (c *Constraint) Validate() error {
	var mErr multierror.Error
	if c.Operand == "" {
		mErr.Errors = append(mErr.Errors, errors.New("Missing constraint operand"))
	}

	// Perform additional validation based on operand
	switch c.Operand {
	case ConstraintRegex:
		if _, err := regexp.Compile(c.RTarget); err != nil {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("Regular expression failed to compile: %v", err))
		}
	case ConstraintVersion:
		if _, err := version.NewConstraint(c.RTarget); err != nil {
			mErr.Errors = append(mErr.Errors, fmt.Errorf("Version constraint is invalid: %v", err))
		}
	}
	return mErr.ErrorOrNil()
}

// EphemeralDisk is an ephemeral disk object
type EphemeralDisk struct {
	// Sticky indicates whether the allocation is sticky to a node
	Sticky bool

	// SizeMB is the size of the local disk
	SizeMB int `mapstructure:"size"`
}

// DefaultEphemeralDisk returns a EphemeralDisk with default configurations
func DefaultEphemeralDisk() *EphemeralDisk {
	return &EphemeralDisk{
		SizeMB: 300,
	}
}

// Validate validates EphemeralDisk
func (d *EphemeralDisk) Validate() error {
	if d.SizeMB < 10 {
		return fmt.Errorf("minimum DiskMB value is 10; got %d", d.SizeMB)
	}
	return nil
}

// Copy copies the EphemeralDisk struct and returns a new one
func (d *EphemeralDisk) Copy() *EphemeralDisk {
	ld := new(EphemeralDisk)
	*ld = *d
	return ld
}

// Vault stores the set of premissions a task needs access to from Vault.
type Vault struct {
	// Policies is the set of policies that the task needs access to
	Policies []string
}

// Copy returns a copy of this Vault block.
func (v *Vault) Copy() *Vault {
	if v == nil {
		return nil
	}

	nv := new(Vault)
	*nv = *v
	return nv
}

// Validate returns if the Vault block is valid.
func (v *Vault) Validate() error {
	if v == nil {
		return nil
	}

	if len(v.Policies) == 0 {
		return fmt.Errorf("Policy list can not be empty")
	}

	return nil
}

const (
	AllocDesiredStatusRun   = "run"   // Allocation should run
	AllocDesiredStatusStop  = "stop"  // Allocation should stop
	AllocDesiredStatusEvict = "evict" // Allocation should stop, and was evicted
)

const (
	AllocClientStatusPending  = "pending"
	AllocClientStatusRunning  = "running"
	AllocClientStatusComplete = "complete"
	AllocClientStatusFailed   = "failed"
	AllocClientStatusLost     = "lost"
)

// Allocation is used to allocate the placement of a task group to a node.
type Allocation struct {
	// ID of the allocation (UUID)
	ID string

	// ID of the evaluation that generated this allocation
	EvalID string

	// Name is a logical name of the allocation.
	Name string

	// NodeID is the node this is being placed on
	NodeID string

	// Job is the parent job of the task group being allocated.
	// This is copied at allocation time to avoid issues if the job
	// definition is updated.
	JobID string
	Job   *Job

	// TaskGroup is the name of the task group that should be run
	TaskGroup string

	// Resources is the total set of resources allocated as part
	// of this allocation of the task group.
	Resources *Resources

	// SharedResources are the resources that are shared by all the tasks in an
	// allocation
	SharedResources *Resources

	// TaskResources is the set of resources allocated to each
	// task. These should sum to the total Resources.
	TaskResources map[string]*Resources

	// Metrics associated with this allocation
	Metrics *AllocMetric

	// Desired Status of the allocation on the client
	DesiredStatus string

	// DesiredStatusDescription is meant to provide more human useful information
	DesiredDescription string

	// Status of the allocation on the client
	ClientStatus string

	// ClientStatusDescription is meant to provide more human useful information
	ClientDescription string

	// TaskStates stores the state of each task,
	TaskStates map[string]*TaskState

	// PreviousAllocation is the allocation that this allocation is replacing
	PreviousAllocation string

	// Raft Indexes
	CreateIndex uint64
	ModifyIndex uint64

	// AllocModifyIndex is not updated when the client updates allocations. This
	// lets the client pull only the allocs updated by the server.
	AllocModifyIndex uint64

	// CreateTime is the time the allocation has finished scheduling and been
	// verified by the plan applier.
	CreateTime int64
}

func (a *Allocation) Copy() *Allocation {
	if a == nil {
		return nil
	}
	na := new(Allocation)
	*na = *a

	na.Job = na.Job.Copy()
	na.Resources = na.Resources.Copy()
	na.SharedResources = na.SharedResources.Copy()

	if a.TaskResources != nil {
		tr := make(map[string]*Resources, len(na.TaskResources))
		for task, resource := range na.TaskResources {
			tr[task] = resource.Copy()
		}
		na.TaskResources = tr
	}

	na.Metrics = na.Metrics.Copy()

	if a.TaskStates != nil {
		ts := make(map[string]*TaskState, len(na.TaskStates))
		for task, state := range na.TaskStates {
			ts[task] = state.Copy()
		}
		na.TaskStates = ts
	}
	return na
}

// TerminalStatus returns if the desired or actual status is terminal and
// will no longer transition.
func (a *Allocation) TerminalStatus() bool {
	// First check the desired state and if that isn't terminal, check client
	// state.
	switch a.DesiredStatus {
	case AllocDesiredStatusStop, AllocDesiredStatusEvict:
		return true
	default:
	}

	switch a.ClientStatus {
	case AllocClientStatusComplete, AllocClientStatusFailed, AllocClientStatusLost:
		return true
	default:
		return false
	}
}

// Terminated returns if the allocation is in a terminal state on a client.
func (a *Allocation) Terminated() bool {
	if a.ClientStatus == AllocClientStatusFailed ||
		a.ClientStatus == AllocClientStatusComplete ||
		a.ClientStatus == AllocClientStatusLost {
		return true
	}
	return false
}

// RanSuccessfully returns whether the client has ran the allocation and all
// tasks finished successfully
func (a *Allocation) RanSuccessfully() bool {
	// Handle the case the client hasn't started the allocation.
	if len(a.TaskStates) == 0 {
		return false
	}

	// Check to see if all the tasks finised successfully in the allocation
	allSuccess := true
	for _, state := range a.TaskStates {
		allSuccess = allSuccess && state.Successful()
	}

	return allSuccess
}

// Stub returns a list stub for the allocation
func (a *Allocation) Stub() *AllocListStub {
	return &AllocListStub{
		ID:                 a.ID,
		EvalID:             a.EvalID,
		Name:               a.Name,
		NodeID:             a.NodeID,
		JobID:              a.JobID,
		TaskGroup:          a.TaskGroup,
		DesiredStatus:      a.DesiredStatus,
		DesiredDescription: a.DesiredDescription,
		ClientStatus:       a.ClientStatus,
		ClientDescription:  a.ClientDescription,
		TaskStates:         a.TaskStates,
		CreateIndex:        a.CreateIndex,
		ModifyIndex:        a.ModifyIndex,
		CreateTime:         a.CreateTime,
	}
}

var (
	// AllocationIndexRegex is a regular expression to find the allocation index.
	AllocationIndexRegex = regexp.MustCompile(".+\\[(\\d+)\\]$")
)

// Index returns the index of the allocation. If the allocation is from a task
// group with count greater than 1, there will be multiple allocations for it.
func (a *Allocation) Index() int {
	matches := AllocationIndexRegex.FindStringSubmatch(a.Name)
	if len(matches) != 2 {
		return -1
	}

	index, err := strconv.Atoi(matches[1])
	if err != nil {
		return -1
	}

	return index
}

// AllocListStub is used to return a subset of alloc information
type AllocListStub struct {
	ID                 string
	EvalID             string
	Name               string
	NodeID             string
	JobID              string
	TaskGroup          string
	DesiredStatus      string
	DesiredDescription string
	ClientStatus       string
	ClientDescription  string
	TaskStates         map[string]*TaskState
	CreateIndex        uint64
	ModifyIndex        uint64
	CreateTime         int64
}

// AllocMetric is used to track various metrics while attempting
// to make an allocation. These are used to debug a job, or to better
// understand the pressure within the system.
type AllocMetric struct {
	// NodesEvaluated is the number of nodes that were evaluated
	NodesEvaluated int

	// NodesFiltered is the number of nodes filtered due to a constraint
	NodesFiltered int

	// NodesAvailable is the number of nodes available for evaluation per DC.
	NodesAvailable map[string]int

	// ClassFiltered is the number of nodes filtered by class
	ClassFiltered map[string]int

	// ConstraintFiltered is the number of failures caused by constraint
	ConstraintFiltered map[string]int

	// NodesExhausted is the number of nodes skipped due to being
	// exhausted of at least one resource
	NodesExhausted int

	// ClassExhausted is the number of nodes exhausted by class
	ClassExhausted map[string]int

	// DimensionExhausted provides the count by dimension or reason
	DimensionExhausted map[string]int

	// Scores is the scores of the final few nodes remaining
	// for placement. The top score is typically selected.
	Scores map[string]float64

	// AllocationTime is a measure of how long the allocation
	// attempt took. This can affect performance and SLAs.
	AllocationTime time.Duration

	// CoalescedFailures indicates the number of other
	// allocations that were coalesced into this failed allocation.
	// This is to prevent creating many failed allocations for a
	// single task group.
	CoalescedFailures int
}

func (a *AllocMetric) Copy() *AllocMetric {
	if a == nil {
		return nil
	}
	na := new(AllocMetric)
	*na = *a
	na.NodesAvailable = CopyMapStringInt(na.NodesAvailable)
	na.ClassFiltered = CopyMapStringInt(na.ClassFiltered)
	na.ConstraintFiltered = CopyMapStringInt(na.ConstraintFiltered)
	na.ClassExhausted = CopyMapStringInt(na.ClassExhausted)
	na.DimensionExhausted = CopyMapStringInt(na.DimensionExhausted)
	na.Scores = CopyMapStringFloat64(na.Scores)
	return na
}

func (a *AllocMetric) EvaluateNode() {
	a.NodesEvaluated += 1
}

func (a *AllocMetric) FilterNode(node *Node, constraint string) {
	a.NodesFiltered += 1
	if node != nil && node.NodeClass != "" {
		if a.ClassFiltered == nil {
			a.ClassFiltered = make(map[string]int)
		}
		a.ClassFiltered[node.NodeClass] += 1
	}
	if constraint != "" {
		if a.ConstraintFiltered == nil {
			a.ConstraintFiltered = make(map[string]int)
		}
		a.ConstraintFiltered[constraint] += 1
	}
}

func (a *AllocMetric) ExhaustedNode(node *Node, dimension string) {
	a.NodesExhausted += 1
	if node != nil && node.NodeClass != "" {
		if a.ClassExhausted == nil {
			a.ClassExhausted = make(map[string]int)
		}
		a.ClassExhausted[node.NodeClass] += 1
	}
	if dimension != "" {
		if a.DimensionExhausted == nil {
			a.DimensionExhausted = make(map[string]int)
		}
		a.DimensionExhausted[dimension] += 1
	}
}

func (a *AllocMetric) ScoreNode(node *Node, name string, score float64) {
	if a.Scores == nil {
		a.Scores = make(map[string]float64)
	}
	key := fmt.Sprintf("%s.%s", node.ID, name)
	a.Scores[key] = score
}

const (
	EvalStatusBlocked   = "blocked"
	EvalStatusPending   = "pending"
	EvalStatusComplete  = "complete"
	EvalStatusFailed    = "failed"
	EvalStatusCancelled = "canceled"
)

const (
	EvalTriggerJobRegister   = "job-register"
	EvalTriggerJobDeregister = "job-deregister"
	EvalTriggerPeriodicJob   = "periodic-job"
	EvalTriggerNodeUpdate    = "node-update"
	EvalTriggerScheduled     = "scheduled"
	EvalTriggerRollingUpdate = "rolling-update"
	EvalTriggerMaxPlans      = "max-plan-attempts"
)

const (
	// CoreJobEvalGC is used for the garbage collection of evaluations
	// and allocations. We periodically scan evaluations in a terminal state,
	// in which all the corresponding allocations are also terminal. We
	// delete these out of the system to bound the state.
	CoreJobEvalGC = "eval-gc"

	// CoreJobNodeGC is used for the garbage collection of failed nodes.
	// We periodically scan nodes in a terminal state, and if they have no
	// corresponding allocations we delete these out of the system.
	CoreJobNodeGC = "node-gc"

	// CoreJobJobGC is used for the garbage collection of eligible jobs. We
	// periodically scan garbage collectible jobs and check if both their
	// evaluations and allocations are terminal. If so, we delete these out of
	// the system.
	CoreJobJobGC = "job-gc"

	// CoreJobForceGC is used to force garbage collection of all GCable objects.
	CoreJobForceGC = "force-gc"
)

// Evaluation is used anytime we need to apply business logic as a result
// of a change to our desired state (job specification) or the emergent state
// (registered nodes). When the inputs change, we need to "evaluate" them,
// potentially taking action (allocation of work) or doing nothing if the state
// of the world does not require it.
type Evaluation struct {
	// ID is a randonly generated UUID used for this evaluation. This
	// is assigned upon the creation of the evaluation.
	ID string

	// Priority is used to control scheduling importance and if this job
	// can preempt other jobs.
	Priority int

	// Type is used to control which schedulers are available to handle
	// this evaluation.
	Type string

	// TriggeredBy is used to give some insight into why this Eval
	// was created. (Job change, node failure, alloc failure, etc).
	TriggeredBy string

	// JobID is the job this evaluation is scoped to. Evaluations cannot
	// be run in parallel for a given JobID, so we serialize on this.
	JobID string

	// JobModifyIndex is the modify index of the job at the time
	// the evaluation was created
	JobModifyIndex uint64

	// NodeID is the node that was affected triggering the evaluation.
	NodeID string

	// NodeModifyIndex is the modify index of the node at the time
	// the evaluation was created
	NodeModifyIndex uint64

	// Status of the evaluation
	Status string

	// StatusDescription is meant to provide more human useful information
	StatusDescription string

	// Wait is a minimum wait time for running the eval. This is used to
	// support a rolling upgrade.
	Wait time.Duration

	// NextEval is the evaluation ID for the eval created to do a followup.
	// This is used to support rolling upgrades, where we need a chain of evaluations.
	NextEval string

	// PreviousEval is the evaluation ID for the eval creating this one to do a followup.
	// This is used to support rolling upgrades, where we need a chain of evaluations.
	PreviousEval string

	// BlockedEval is the evaluation ID for a created blocked eval. A
	// blocked eval will be created if all allocations could not be placed due
	// to constraints or lacking resources.
	BlockedEval string

	// FailedTGAllocs are task groups which have allocations that could not be
	// made, but the metrics are persisted so that the user can use the feedback
	// to determine the cause.
	FailedTGAllocs map[string]*AllocMetric

	// ClassEligibility tracks computed node classes that have been explicitly
	// marked as eligible or ineligible.
	ClassEligibility map[string]bool

	// EscapedComputedClass marks whether the job has constraints that are not
	// captured by computed node classes.
	EscapedComputedClass bool

	// AnnotatePlan triggers the scheduler to provide additional annotations
	// during the evaluation. This should not be set during normal operations.
	AnnotatePlan bool

	// SnapshotIndex is the Raft index of the snapshot used to process the
	// evaluation. As such it will only be set once it has gone through the
	// scheduler.
	SnapshotIndex uint64

	// QueuedAllocations is the number of unplaced allocations at the time the
	// evaluation was processed. The map is keyed by Task Group names.
	QueuedAllocations map[string]int

	// Raft Indexes
	CreateIndex uint64
	ModifyIndex uint64
}

// TerminalStatus returns if the current status is terminal and
// will no longer transition.
func (e *Evaluation) TerminalStatus() bool {
	switch e.Status {
	case EvalStatusComplete, EvalStatusFailed, EvalStatusCancelled:
		return true
	default:
		return false
	}
}

func (e *Evaluation) GoString() string {
	return fmt.Sprintf("<Eval '%s' JobID: '%s'>", e.ID, e.JobID)
}

func (e *Evaluation) Copy() *Evaluation {
	if e == nil {
		return nil
	}
	ne := new(Evaluation)
	*ne = *e

	// Copy ClassEligibility
	if e.ClassEligibility != nil {
		classes := make(map[string]bool, len(e.ClassEligibility))
		for class, elig := range e.ClassEligibility {
			classes[class] = elig
		}
		ne.ClassEligibility = classes
	}

	// Copy FailedTGAllocs
	if e.FailedTGAllocs != nil {
		failedTGs := make(map[string]*AllocMetric, len(e.FailedTGAllocs))
		for tg, metric := range e.FailedTGAllocs {
			failedTGs[tg] = metric.Copy()
		}
		ne.FailedTGAllocs = failedTGs
	}

	// Copy queued allocations
	if e.QueuedAllocations != nil {
		queuedAllocations := make(map[string]int, len(e.QueuedAllocations))
		for tg, num := range e.QueuedAllocations {
			queuedAllocations[tg] = num
		}
		ne.QueuedAllocations = queuedAllocations
	}

	return ne
}

// ShouldEnqueue checks if a given evaluation should be enqueued into the
// eval_broker
func (e *Evaluation) ShouldEnqueue() bool {
	switch e.Status {
	case EvalStatusPending:
		return true
	case EvalStatusComplete, EvalStatusFailed, EvalStatusBlocked, EvalStatusCancelled:
		return false
	default:
		panic(fmt.Sprintf("unhandled evaluation (%s) status %s", e.ID, e.Status))
	}
}

// ShouldBlock checks if a given evaluation should be entered into the blocked
// eval tracker.
func (e *Evaluation) ShouldBlock() bool {
	switch e.Status {
	case EvalStatusBlocked:
		return true
	case EvalStatusComplete, EvalStatusFailed, EvalStatusPending, EvalStatusCancelled:
		return false
	default:
		panic(fmt.Sprintf("unhandled evaluation (%s) status %s", e.ID, e.Status))
	}
}

// MakePlan is used to make a plan from the given evaluation
// for a given Job
func (e *Evaluation) MakePlan(j *Job) *Plan {
	p := &Plan{
		EvalID:         e.ID,
		Priority:       e.Priority,
		Job:            j,
		NodeUpdate:     make(map[string][]*Allocation),
		NodeAllocation: make(map[string][]*Allocation),
	}
	if j != nil {
		p.AllAtOnce = j.AllAtOnce
	}
	return p
}

// NextRollingEval creates an evaluation to followup this eval for rolling updates
func (e *Evaluation) NextRollingEval(wait time.Duration) *Evaluation {
	return &Evaluation{
		ID:             GenerateUUID(),
		Priority:       e.Priority,
		Type:           e.Type,
		TriggeredBy:    EvalTriggerRollingUpdate,
		JobID:          e.JobID,
		JobModifyIndex: e.JobModifyIndex,
		Status:         EvalStatusPending,
		Wait:           wait,
		PreviousEval:   e.ID,
	}
}

// CreateBlockedEval creates a blocked evaluation to followup this eval to place any
// failed allocations. It takes the classes marked explicitly eligible or
// ineligible and whether the job has escaped computed node classes.
func (e *Evaluation) CreateBlockedEval(classEligibility map[string]bool, escaped bool) *Evaluation {
	return &Evaluation{
		ID:                   GenerateUUID(),
		Priority:             e.Priority,
		Type:                 e.Type,
		TriggeredBy:          e.TriggeredBy,
		JobID:                e.JobID,
		JobModifyIndex:       e.JobModifyIndex,
		Status:               EvalStatusBlocked,
		PreviousEval:         e.ID,
		ClassEligibility:     classEligibility,
		EscapedComputedClass: escaped,
	}
}

// Plan is used to submit a commit plan for task allocations. These
// are submitted to the leader which verifies that resources have
// not been overcommitted before admiting the plan.
type Plan struct {
	// EvalID is the evaluation ID this plan is associated with
	EvalID string

	// EvalToken is used to prevent a split-brain processing of
	// an evaluation. There should only be a single scheduler running
	// an Eval at a time, but this could be violated after a leadership
	// transition. This unique token is used to reject plans that are
	// being submitted from a different leader.
	EvalToken string

	// Priority is the priority of the upstream job
	Priority int

	// AllAtOnce is used to control if incremental scheduling of task groups
	// is allowed or if we must do a gang scheduling of the entire job.
	// If this is false, a plan may be partially applied. Otherwise, the
	// entire plan must be able to make progress.
	AllAtOnce bool

	// Job is the parent job of all the allocations in the Plan.
	// Since a Plan only involves a single Job, we can reduce the size
	// of the plan by only including it once.
	Job *Job

	// NodeUpdate contains all the allocations for each node. For each node,
	// this is a list of the allocations to update to either stop or evict.
	NodeUpdate map[string][]*Allocation

	// NodeAllocation contains all the allocations for each node.
	// The evicts must be considered prior to the allocations.
	NodeAllocation map[string][]*Allocation

	// Annotations contains annotations by the scheduler to be used by operators
	// to understand the decisions made by the scheduler.
	Annotations *PlanAnnotations
}

// AppendUpdate marks the allocation for eviction. The clientStatus of the
// allocation may be optionally set by passing in a non-empty value.
func (p *Plan) AppendUpdate(alloc *Allocation, desiredStatus, desiredDesc, clientStatus string) {
	newAlloc := new(Allocation)
	*newAlloc = *alloc

	// If the job is not set in the plan we are deregistering a job so we
	// extract the job from the allocation.
	if p.Job == nil && newAlloc.Job != nil {
		p.Job = newAlloc.Job
	}

	// Normalize the job
	newAlloc.Job = nil

	// Strip the resources as it can be rebuilt.
	newAlloc.Resources = nil

	newAlloc.DesiredStatus = desiredStatus
	newAlloc.DesiredDescription = desiredDesc

	if clientStatus != "" {
		newAlloc.ClientStatus = clientStatus
	}

	node := alloc.NodeID
	existing := p.NodeUpdate[node]
	p.NodeUpdate[node] = append(existing, newAlloc)
}

func (p *Plan) PopUpdate(alloc *Allocation) {
	existing := p.NodeUpdate[alloc.NodeID]
	n := len(existing)
	if n > 0 && existing[n-1].ID == alloc.ID {
		existing = existing[:n-1]
		if len(existing) > 0 {
			p.NodeUpdate[alloc.NodeID] = existing
		} else {
			delete(p.NodeUpdate, alloc.NodeID)
		}
	}
}

func (p *Plan) AppendAlloc(alloc *Allocation) {
	node := alloc.NodeID
	existing := p.NodeAllocation[node]
	p.NodeAllocation[node] = append(existing, alloc)
}

// IsNoOp checks if this plan would do nothing
func (p *Plan) IsNoOp() bool {
	return len(p.NodeUpdate) == 0 && len(p.NodeAllocation) == 0
}

// PlanResult is the result of a plan submitted to the leader.
type PlanResult struct {
	// NodeUpdate contains all the updates that were committed.
	NodeUpdate map[string][]*Allocation

	// NodeAllocation contains all the allocations that were committed.
	NodeAllocation map[string][]*Allocation

	// RefreshIndex is the index the worker should refresh state up to.
	// This allows all evictions and allocations to be materialized.
	// If any allocations were rejected due to stale data (node state,
	// over committed) this can be used to force a worker refresh.
	RefreshIndex uint64

	// AllocIndex is the Raft index in which the evictions and
	// allocations took place. This is used for the write index.
	AllocIndex uint64
}

// IsNoOp checks if this plan result would do nothing
func (p *PlanResult) IsNoOp() bool {
	return len(p.NodeUpdate) == 0 && len(p.NodeAllocation) == 0
}

// FullCommit is used to check if all the allocations in a plan
// were committed as part of the result. Returns if there was
// a match, and the number of expected and actual allocations.
func (p *PlanResult) FullCommit(plan *Plan) (bool, int, int) {
	expected := 0
	actual := 0
	for name, allocList := range plan.NodeAllocation {
		didAlloc, _ := p.NodeAllocation[name]
		expected += len(allocList)
		actual += len(didAlloc)
	}
	return actual == expected, expected, actual
}

// PlanAnnotations holds annotations made by the scheduler to give further debug
// information to operators.
type PlanAnnotations struct {
	// DesiredTGUpdates is the set of desired updates per task group.
	DesiredTGUpdates map[string]*DesiredUpdates
}

// DesiredUpdates is the set of changes the scheduler would like to make given
// sufficient resources and cluster capacity.
type DesiredUpdates struct {
	Ignore            uint64
	Place             uint64
	Migrate           uint64
	Stop              uint64
	InPlaceUpdate     uint64
	DestructiveUpdate uint64
}

// msgpackHandle is a shared handle for encoding/decoding of structs
var MsgpackHandle = func() *codec.MsgpackHandle {
	h := &codec.MsgpackHandle{RawToString: true}

	// Sets the default type for decoding a map into a nil interface{}.
	// This is necessary in particular because we store the driver configs as a
	// nil interface{}.
	h.MapType = reflect.TypeOf(map[string]interface{}(nil))
	return h
}()

var HashiMsgpackHandle = func() *hcodec.MsgpackHandle {
	h := &hcodec.MsgpackHandle{RawToString: true}

	// Sets the default type for decoding a map into a nil interface{}.
	// This is necessary in particular because we store the driver configs as a
	// nil interface{}.
	h.MapType = reflect.TypeOf(map[string]interface{}(nil))
	return h
}()

// Decode is used to decode a MsgPack encoded object
func Decode(buf []byte, out interface{}) error {
	return codec.NewDecoder(bytes.NewReader(buf), MsgpackHandle).Decode(out)
}

// Encode is used to encode a MsgPack object with type prefix
func Encode(t MessageType, msg interface{}) ([]byte, error) {
	var buf bytes.Buffer
	buf.WriteByte(uint8(t))
	err := codec.NewEncoder(&buf, MsgpackHandle).Encode(msg)
	return buf.Bytes(), err
}