github.com/makyo/juju@v0.0.0-20160425123129-2608902037e9/provider/lxd/environ_instance.go (about)

     1  // Copyright 2015 Canonical Ltd.
     2  // Licensed under the AGPLv3, see LICENCE file for details.
     3  
     4  // +build go1.3
     5  
     6  package lxd
     7  
     8  import (
     9  	"github.com/juju/errors"
    10  
    11  	"github.com/juju/juju/environs"
    12  	"github.com/juju/juju/environs/tags"
    13  	"github.com/juju/juju/instance"
    14  	"github.com/juju/juju/provider/common"
    15  	"github.com/juju/juju/tools/lxdclient"
    16  )
    17  
    18  // Instances returns the available instances in the environment that
    19  // match the provided instance IDs. For IDs that did not match any
    20  // instances, the result at the corresponding index will be nil. In that
    21  // case the error will be environs.ErrPartialInstances (or
    22  // ErrNoInstances if none of the IDs match an instance).
    23  func (env *environ) Instances(ids []instance.Id) ([]instance.Instance, error) {
    24  	if len(ids) == 0 {
    25  		return nil, environs.ErrNoInstances
    26  	}
    27  
    28  	instances, err := env.allInstances()
    29  	if err != nil {
    30  		// We don't return the error since we need to pack one instance
    31  		// for each ID into the result. If there is a problem then we
    32  		// will return either ErrPartialInstances or ErrNoInstances.
    33  		// TODO(ericsnow) Skip returning here only for certain errors?
    34  		logger.Errorf("failed to get instances from LXD: %v", err)
    35  		err = errors.Trace(err)
    36  	}
    37  
    38  	// Build the result, matching the provided instance IDs.
    39  	numFound := 0 // This will never be greater than len(ids).
    40  	results := make([]instance.Instance, len(ids))
    41  	for i, id := range ids {
    42  		inst := findInst(id, instances)
    43  		if inst != nil {
    44  			numFound++
    45  		}
    46  		results[i] = inst
    47  	}
    48  
    49  	if numFound == 0 {
    50  		if err == nil {
    51  			err = environs.ErrNoInstances
    52  		}
    53  	} else if numFound != len(ids) {
    54  		err = environs.ErrPartialInstances
    55  	}
    56  	return results, err
    57  }
    58  
    59  func findInst(id instance.Id, instances []*environInstance) instance.Instance {
    60  	for _, inst := range instances {
    61  		if id == inst.Id() {
    62  			return inst
    63  		}
    64  	}
    65  	return nil
    66  }
    67  
    68  // instances returns a list of all "alive" instances in the environment.
    69  // We match machine names to the pattern "juju-<model-UUID>-machine-*"
    70  // to ensure that only machines for the environment are returned. This
    71  // is necessary to isolate multiple models within the same LXD.
    72  func (env *environ) allInstances() ([]*environInstance, error) {
    73  	prefix := common.MachineFullName(env.Config().UUID(), "")
    74  	return env.prefixedInstances(prefix)
    75  }
    76  
    77  // prefixedInstances returns instances with the specified prefix.
    78  func (env *environ) prefixedInstances(prefix string) ([]*environInstance, error) {
    79  	instances, err := env.raw.Instances(prefix, lxdclient.AliveStatuses...)
    80  	err = errors.Trace(err)
    81  
    82  	// Turn lxdclient.Instance values into *environInstance values,
    83  	// whether or not we got an error.
    84  	var results []*environInstance
    85  	for _, base := range instances {
    86  		// If we don't make a copy then the same pointer is used for the
    87  		// base of all resulting instances.
    88  		copied := base
    89  		inst := newInstance(&copied, env)
    90  		results = append(results, inst)
    91  	}
    92  	return results, err
    93  }
    94  
    95  // ControllerInstances returns the IDs of the instances corresponding
    96  // to juju controllers.
    97  func (env *environ) ControllerInstances() ([]instance.Id, error) {
    98  	prefix := common.MachineFullName(env.Config().ControllerUUID(), "")
    99  	instances, err := env.raw.Instances(prefix, lxdclient.AliveStatuses...)
   100  	if err != nil {
   101  		return nil, errors.Trace(err)
   102  	}
   103  
   104  	var results []instance.Id
   105  	for _, inst := range instances {
   106  		if inst.Metadata()[tags.JujuIsController] == "true" {
   107  			results = append(results, instance.Id(inst.Name))
   108  		}
   109  	}
   110  	if len(results) == 0 {
   111  		return nil, environs.ErrNotBootstrapped
   112  	}
   113  	return results, nil
   114  }
   115  
   116  type instPlacement struct{}
   117  
   118  func (env *environ) parsePlacement(placement string) (*instPlacement, error) {
   119  	if placement == "" {
   120  		return &instPlacement{}, nil
   121  	}
   122  
   123  	return nil, errors.Errorf("unknown placement directive: %v", placement)
   124  }