terraform/command/diff.go

102 lines
2.2 KiB
Go

package command
import (
"flag"
"fmt"
"os"
"strings"
"github.com/hashicorp/terraform/config"
"github.com/hashicorp/terraform/terraform"
"github.com/mitchellh/cli"
)
// DiffCommand is a Command implementation that compares a Terraform
// configuration to an actual infrastructure and shows the differences.
type DiffCommand struct {
TFConfig *terraform.Config
Ui cli.Ui
}
func (c *DiffCommand) Run(args []string) int {
var statePath string
cmdFlags := flag.NewFlagSet("diff", flag.ContinueOnError)
cmdFlags.StringVar(&statePath, "state", "", "path")
cmdFlags.Usage = func() { c.Ui.Error(c.Help()) }
if err := cmdFlags.Parse(args); err != nil {
return 1
}
args = cmdFlags.Args()
if len(args) != 1 {
c.Ui.Error(
"The diff command expects only one argument with the path\n" +
"to a Terraform configuration.\n")
cmdFlags.Usage()
return 1
}
// Load up the state
var state *terraform.State
if statePath != "" {
f, err := os.Open(statePath)
if err != nil {
c.Ui.Error(fmt.Sprintf("Error loading state: %s", err))
return 1
}
state, err = terraform.ReadState(f)
f.Close()
if err != nil {
c.Ui.Error(fmt.Sprintf("Error loading state: %s", err))
return 1
}
}
b, err := config.Load(args[0])
if err != nil {
c.Ui.Error(fmt.Sprintf("Error loading blueprint: %s", err))
return 1
}
tfconfig := c.TFConfig
tfconfig.Config = b
tf, err := terraform.New(tfconfig)
if err != nil {
c.Ui.Error(fmt.Sprintf("Error initializing Terraform: %s", err))
return 1
}
diff, err := tf.Diff(state)
if err != nil {
c.Ui.Error(fmt.Sprintf("Error running diff: %s", err))
return 1
}
c.Ui.Output(strings.TrimSpace(diff.String()))
return 0
}
func (c *DiffCommand) Help() string {
helpText := `
Usage: terraform diff [options] [terraform.tf]
Shows the differences between the Terraform configuration and
the actual state of an infrastructure.
Options:
-state=statefile Path to a Terraform state file to use to look
up Terraform-managed resources.
`
return strings.TrimSpace(helpText)
}
func (c *DiffCommand) Synopsis() string {
return "Show changes between Terraform config and infrastructure"
}