github.com/iaas-resource-provision/iaas-rpc@v1.0.7-0.20211021023331-ed21f798c408/internal/backend/remote-state/etcdv3/backend_state.go (about)

     1  package etcd
     2  
     3  import (
     4  	"context"
     5  	"fmt"
     6  	"sort"
     7  	"strings"
     8  
     9  	etcdv3 "go.etcd.io/etcd/clientv3"
    10  
    11  	"github.com/iaas-resource-provision/iaas-rpc/internal/backend"
    12  	"github.com/iaas-resource-provision/iaas-rpc/internal/states"
    13  	"github.com/iaas-resource-provision/iaas-rpc/internal/states/remote"
    14  	"github.com/iaas-resource-provision/iaas-rpc/internal/states/statemgr"
    15  )
    16  
    17  func (b *Backend) Workspaces() ([]string, error) {
    18  	res, err := b.client.Get(context.TODO(), b.prefix, etcdv3.WithPrefix(), etcdv3.WithKeysOnly())
    19  	if err != nil {
    20  		return nil, err
    21  	}
    22  
    23  	result := make([]string, 1, len(res.Kvs)+1)
    24  	result[0] = backend.DefaultStateName
    25  	for _, kv := range res.Kvs {
    26  		result = append(result, strings.TrimPrefix(string(kv.Key), b.prefix))
    27  	}
    28  	sort.Strings(result[1:])
    29  
    30  	return result, nil
    31  }
    32  
    33  func (b *Backend) DeleteWorkspace(name string) error {
    34  	if name == backend.DefaultStateName || name == "" {
    35  		return fmt.Errorf("Can't delete default state.")
    36  	}
    37  
    38  	key := b.determineKey(name)
    39  
    40  	_, err := b.client.Delete(context.TODO(), key)
    41  	return err
    42  }
    43  
    44  func (b *Backend) StateMgr(name string) (statemgr.Full, error) {
    45  	var stateMgr statemgr.Full = &remote.State{
    46  		Client: &RemoteClient{
    47  			Client: b.client,
    48  			DoLock: b.lock,
    49  			Key:    b.determineKey(name),
    50  		},
    51  	}
    52  
    53  	if !b.lock {
    54  		stateMgr = &statemgr.LockDisabled{Inner: stateMgr}
    55  	}
    56  
    57  	lockInfo := statemgr.NewLockInfo()
    58  	lockInfo.Operation = "init"
    59  	lockUnlock := func(parent error) error {
    60  		return nil
    61  	}
    62  
    63  	if err := stateMgr.RefreshState(); err != nil {
    64  		err = lockUnlock(err)
    65  		return nil, err
    66  	}
    67  
    68  	if v := stateMgr.State(); v == nil {
    69  		lockId, err := stateMgr.Lock(lockInfo)
    70  		if err != nil {
    71  			return nil, fmt.Errorf("Failed to lock state in etcd: %s.", err)
    72  		}
    73  
    74  		lockUnlock = func(parent error) error {
    75  			if err := stateMgr.Unlock(lockId); err != nil {
    76  				return fmt.Errorf(strings.TrimSpace(errStateUnlock), lockId, err)
    77  			}
    78  			return parent
    79  		}
    80  
    81  		if err := stateMgr.WriteState(states.NewState()); err != nil {
    82  			err = lockUnlock(err)
    83  			return nil, err
    84  		}
    85  		if err := stateMgr.PersistState(); err != nil {
    86  			err = lockUnlock(err)
    87  			return nil, err
    88  		}
    89  	}
    90  
    91  	if err := lockUnlock(nil); err != nil {
    92  		return nil, err
    93  	}
    94  
    95  	return stateMgr, nil
    96  }
    97  
    98  func (b *Backend) determineKey(name string) string {
    99  	return b.prefix + name
   100  }
   101  
   102  const errStateUnlock = `
   103  Error unlocking etcd state. Lock ID: %s
   104  
   105  Error: %s
   106  
   107  You may have to force-unlock this state in order to use it again.
   108  `