opentofu/terraform/plan.go
2014-06-27 14:43:33 -07:00

99 lines
1.9 KiB
Go

package terraform
import (
"bytes"
"encoding/gob"
"errors"
"fmt"
"io"
"sync"
"github.com/hashicorp/terraform/config"
)
// Plan represents a single Terraform execution plan, which contains
// all the information necessary to make an infrastructure change.
type Plan struct {
Config *config.Config
Diff *Diff
State *State
Vars map[string]string
once sync.Once
}
func (p *Plan) String() string {
buf := new(bytes.Buffer)
buf.WriteString("DIFF:\n\n")
buf.WriteString(p.Diff.String())
buf.WriteString("\nSTATE:\n\n")
buf.WriteString(p.State.String())
return buf.String()
}
func (p *Plan) init() {
p.once.Do(func() {
if p.Config == nil {
p.Config = new(config.Config)
}
if p.Diff == nil {
p.Diff = new(Diff)
p.Diff.init()
}
if p.State == nil {
p.State = new(State)
p.State.init()
}
if p.Vars == nil {
p.Vars = make(map[string]string)
}
})
}
// The format byte is prefixed into the plan file format so that we have
// the ability in the future to change the file format if we want for any
// reason.
const planFormatByte byte = 1
// ReadPlan reads a plan structure out of a reader in the format that
// was written by WritePlan.
func ReadPlan(src io.Reader) (*Plan, error) {
var result *Plan
var formatByte [1]byte
n, err := src.Read(formatByte[:])
if err != nil {
return nil, err
}
if n != len(formatByte) {
return nil, errors.New("failed to read plan version byte")
}
if formatByte[0] != planFormatByte {
return nil, fmt.Errorf("unknown plan file version: %d", formatByte[0])
}
dec := gob.NewDecoder(src)
if err := dec.Decode(&result); err != nil {
return nil, err
}
return result, nil
}
// WritePlan writes a plan somewhere in a binary format.
func WritePlan(d *Plan, dst io.Writer) error {
n, err := dst.Write([]byte{planFormatByte})
if err != nil {
return err
}
if n != 1 {
return errors.New("failed to write plan version byte")
}
return gob.NewEncoder(dst).Encode(d)
}