github.com/danp/terraform@v0.9.5-0.20170426144147-39d740081351/state/remote/state.go (about)

     1  package remote
     2  
     3  import (
     4  	"bytes"
     5  
     6  	"github.com/hashicorp/terraform/state"
     7  	"github.com/hashicorp/terraform/terraform"
     8  )
     9  
    10  // State implements the State interfaces in the state package to handle
    11  // reading and writing the remote state. This State on its own does no
    12  // local caching so every persist will go to the remote storage and local
    13  // writes will go to memory.
    14  type State struct {
    15  	Client Client
    16  
    17  	state, readState *terraform.State
    18  }
    19  
    20  // StateReader impl.
    21  func (s *State) State() *terraform.State {
    22  	return s.state.DeepCopy()
    23  }
    24  
    25  // StateWriter impl.
    26  func (s *State) WriteState(state *terraform.State) error {
    27  	s.state = state
    28  	return nil
    29  }
    30  
    31  // StateRefresher impl.
    32  func (s *State) RefreshState() error {
    33  	payload, err := s.Client.Get()
    34  	if err != nil {
    35  		return err
    36  	}
    37  
    38  	// no remote state is OK
    39  	if payload == nil {
    40  		return nil
    41  	}
    42  
    43  	state, err := terraform.ReadState(bytes.NewReader(payload.Data))
    44  	if err != nil {
    45  		return err
    46  	}
    47  
    48  	s.state = state
    49  	s.readState = state
    50  	return nil
    51  }
    52  
    53  // StatePersister impl.
    54  func (s *State) PersistState() error {
    55  	s.state.IncrementSerialMaybe(s.readState)
    56  
    57  	var buf bytes.Buffer
    58  	if err := terraform.WriteState(s.state, &buf); err != nil {
    59  		return err
    60  	}
    61  
    62  	return s.Client.Put(buf.Bytes())
    63  }
    64  
    65  // Lock calls the Client's Lock method if it's implemented.
    66  func (s *State) Lock(info *state.LockInfo) (string, error) {
    67  	if c, ok := s.Client.(ClientLocker); ok {
    68  		return c.Lock(info)
    69  	}
    70  	return "", nil
    71  }
    72  
    73  // Unlock calls the Client's Unlock method if it's implemented.
    74  func (s *State) Unlock(id string) error {
    75  	if c, ok := s.Client.(ClientLocker); ok {
    76  		return c.Unlock(id)
    77  	}
    78  	return nil
    79  }