terraform/internal/backend/remote-state/pg/backend_state.go

116 lines
2.6 KiB
Go

package pg
import (
"fmt"
"github.com/hashicorp/terraform/internal/backend"
"github.com/hashicorp/terraform/states"
"github.com/hashicorp/terraform/states/remote"
"github.com/hashicorp/terraform/states/statemgr"
)
func (b *Backend) Workspaces() ([]string, error) {
query := `SELECT name FROM %s.%s WHERE name != 'default' ORDER BY name`
rows, err := b.db.Query(fmt.Sprintf(query, b.schemaName, statesTableName))
if err != nil {
return nil, err
}
defer rows.Close()
result := []string{
backend.DefaultStateName,
}
for rows.Next() {
var name string
if err := rows.Scan(&name); err != nil {
return nil, err
}
result = append(result, name)
}
if err := rows.Err(); err != nil {
return nil, err
}
return result, nil
}
func (b *Backend) DeleteWorkspace(name string) error {
if name == backend.DefaultStateName || name == "" {
return fmt.Errorf("can't delete default state")
}
query := `DELETE FROM %s.%s WHERE name = $1`
_, err := b.db.Exec(fmt.Sprintf(query, b.schemaName, statesTableName), name)
if err != nil {
return err
}
return nil
}
func (b *Backend) StateMgr(name string) (statemgr.Full, error) {
// Build the state client
var stateMgr statemgr.Full = &remote.State{
Client: &RemoteClient{
Client: b.db,
Name: name,
SchemaName: b.schemaName,
},
}
// Check to see if this state already exists.
// If the state doesn't exist, we have to assume this
// is a normal create operation, and take the lock at that point.
existing, err := b.Workspaces()
if err != nil {
return nil, err
}
exists := false
for _, s := range existing {
if s == name {
exists = true
break
}
}
// Grab a lock, we use this to write an empty state if one doesn't
// exist already. We have to write an empty state as a sentinel value
// so Workspaces() knows it exists.
if !exists {
lockInfo := statemgr.NewLockInfo()
lockInfo.Operation = "init"
lockId, err := stateMgr.Lock(lockInfo)
if err != nil {
return nil, fmt.Errorf("failed to lock state in Postgres: %s", err)
}
// Local helper function so we can call it multiple places
lockUnlock := func(parent error) error {
if err := stateMgr.Unlock(lockId); err != nil {
return fmt.Errorf(`error unlocking Postgres state: %s`, err)
}
return parent
}
if v := stateMgr.State(); v == nil {
if err := stateMgr.WriteState(states.NewState()); err != nil {
err = lockUnlock(err)
return nil, err
}
if err := stateMgr.PersistState(); err != nil {
err = lockUnlock(err)
return nil, err
}
}
// Unlock, the state should now be initialized
if err := lockUnlock(nil); err != nil {
return nil, err
}
}
return stateMgr, nil
}