github.com/nevins-b/terraform@v0.3.8-0.20170215184714-bbae22007d5a/command/state_meta.go (about)

     1  package command
     2  
     3  import (
     4  	"errors"
     5  	"fmt"
     6  	"time"
     7  
     8  	backendlocal "github.com/hashicorp/terraform/backend/local"
     9  	"github.com/hashicorp/terraform/state"
    10  	"github.com/hashicorp/terraform/terraform"
    11  )
    12  
    13  // StateMeta is the meta struct that should be embedded in state subcommands.
    14  type StateMeta struct{}
    15  
    16  // State returns the state for this meta. This is different then Meta.State
    17  // in the way that backups are done. This configures backups to be timestamped
    18  // rather than just the original state path plus a backup path.
    19  func (c *StateMeta) State(m *Meta) (state.State, error) {
    20  	// Disable backups since we wrap it manually below
    21  	m.backupPath = "-"
    22  
    23  	// Load the backend
    24  	b, err := m.Backend(nil)
    25  	if err != nil {
    26  		return nil, err
    27  	}
    28  
    29  	// Get the state
    30  	s, err := b.State()
    31  	if err != nil {
    32  		return nil, err
    33  	}
    34  
    35  	// Get a local backend
    36  	localRaw, err := m.Backend(&BackendOpts{ForceLocal: true})
    37  	if err != nil {
    38  		// This should never fail
    39  		panic(err)
    40  	}
    41  	localB := localRaw.(*backendlocal.Local)
    42  
    43  	// Determine the backup path. stateOutPath is set to the resulting
    44  	// file where state is written (cached in the case of remote state)
    45  	backupPath := fmt.Sprintf(
    46  		"%s.%d%s",
    47  		localB.StateOutPath,
    48  		time.Now().UTC().Unix(),
    49  		DefaultBackupExtension)
    50  
    51  	// Wrap it for backups
    52  	s = &state.BackupState{
    53  		Real: s,
    54  		Path: backupPath,
    55  	}
    56  
    57  	return s, nil
    58  }
    59  
    60  // filterInstance filters a single instance out of filter results.
    61  func (c *StateMeta) filterInstance(rs []*terraform.StateFilterResult) (*terraform.StateFilterResult, error) {
    62  	var result *terraform.StateFilterResult
    63  	for _, r := range rs {
    64  		if _, ok := r.Value.(*terraform.InstanceState); !ok {
    65  			continue
    66  		}
    67  
    68  		if result != nil {
    69  			return nil, errors.New(errStateMultiple)
    70  		}
    71  
    72  		result = r
    73  	}
    74  
    75  	return result, nil
    76  }
    77  
    78  const errStateMultiple = `Multiple instances found for the given pattern!
    79  
    80  This command requires that the pattern match exactly one instance
    81  of a resource. To view the matched instances, use "terraform state list".
    82  Please modify the pattern to match only a single instance.`