Merge pull request #11724 from hashicorp/jbardin/state-locking

add force-unlock command

command/apply_destroy_test.go

@@ -111,7 +111,7 @@ func TestApply_destroyLockedState(t *testing.T) {
 
 	statePath := testStateFile(t, originalState)
 
-	unlock, err := testLockState(statePath)
+	unlock, err := testLockState("./testdata", statePath)
 	if err != nil {
 		t.Fatal(err)
 	}

command/apply_test.go

@@ -63,7 +63,7 @@ func TestApply(t *testing.T) {
 func TestApply_lockedState(t *testing.T) {
 	statePath := testTempFile(t)
 
-	unlock, err := testLockState(statePath)
+	unlock, err := testLockState("./testdata", statePath)
 	if err != nil {
 		t.Fatal(err)
 	}

command/command_test.go

@@ -535,7 +535,9 @@ func testRemoteState(t *testing.T, s *terraform.State, c int) (*terraform.Remote
 
 // testlockState calls a separate process to the lock the state file at path.
 // deferFunc should be called in the caller to properly unlock the file.
-func testLockState(path string) (func(), error) {
+// Since many tests change the working durectory, the sourcedir argument must be
+// supplied to locate the statelocker.go source.
+func testLockState(sourceDir, path string) (func(), error) {
 	// build and run the binary ourselves so we can quickly terminate it for cleanup
 	buildDir, err := ioutil.TempDir("", "locker")
 	if err != nil {
@@ -545,8 +547,10 @@ func testLockState(path string) (func(), error) {
 		os.RemoveAll(buildDir)
 	}
 
+	source := filepath.Join(sourceDir, "statelocker.go")
 	lockBin := filepath.Join(buildDir, "statelocker")
-	out, err := exec.Command("go", "build", "-o", lockBin, "testdata/statelocker.go").CombinedOutput()
+
+	out, err := exec.Command("go", "build", "-o", lockBin, source).CombinedOutput()
 	if err != nil {
 		cleanFunc()
 		return nil, fmt.Errorf("%s %s", err, out)

command/plan_test.go

@@ -46,7 +46,7 @@ func TestPlan_lockedState(t *testing.T) {
 	}
 
 	testPath := testFixturePath("plan")
-	unlock, err := testLockState(filepath.Join(testPath, DefaultStateFilename))
+	unlock, err := testLockState("./testdata", filepath.Join(testPath, DefaultStateFilename))
 	if err != nil {
 		t.Fatal(err)
 	}

command/refresh_test.go

@@ -63,7 +63,7 @@ func TestRefresh_lockedState(t *testing.T) {
 	state := testState()
 	statePath := testStateFile(t, state)
 
-	unlock, err := testLockState(statePath)
+	unlock, err := testLockState("./testdata", statePath)
 	if err != nil {
 		t.Fatal(err)
 	}

command/taint_test.go

@@ -63,7 +63,7 @@ func TestTaint_lockedState(t *testing.T) {
 	}
 	statePath := testStateFile(t, state)
 
-	unlock, err := testLockState(statePath)
+	unlock, err := testLockState("./testdata", statePath)
 	if err != nil {
 		t.Fatal(err)
 	}

command/unlock.go

@@ -0,0 +1,131 @@
+package command
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/hashicorp/terraform/state"
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// UnlockCommand is a cli.Command implementation that manually unlocks
+// the state.
+type UnlockCommand struct {
+	Meta
+}
+
+func (c *UnlockCommand) Run(args []string) int {
+	args = c.Meta.process(args, false)
+
+	force := false
+	cmdFlags := c.Meta.flagSet("force-unlock")
+	cmdFlags.BoolVar(&force, "force", false, "force")
+	cmdFlags.Usage = func() { c.Ui.Error(c.Help()) }
+	if err := cmdFlags.Parse(args); err != nil {
+		return 1
+	}
+
+	// assume everything is initialized. The user can manually init if this is
+	// required.
+	configPath, err := ModulePath(cmdFlags.Args())
+	if err != nil {
+		c.Ui.Error(err.Error())
+		return 1
+	}
+
+	// Load the backend
+	b, err := c.Backend(&BackendOpts{
+		ConfigPath: configPath,
+	})
+	if err != nil {
+		c.Ui.Error(fmt.Sprintf("Failed to load backend: %s", err))
+		return 1
+	}
+
+	st, err := b.State()
+	if err != nil {
+		c.Ui.Error(fmt.Sprintf("Failed to load state: %s", err))
+		return 1
+	}
+
+	s, ok := st.(state.Locker)
+	if !ok {
+		c.Ui.Error("The remote state backend in use does not support locking, and therefor\n" +
+			"cannot be unlocked.")
+		return 1
+	}
+
+	isLocal := false
+	switch s := st.(type) {
+	case *state.BackupState:
+		if _, ok := s.Real.(*state.LocalState); ok {
+			isLocal = true
+		}
+	case *state.LocalState:
+		isLocal = true
+	}
+
+	if !force {
+		// Forcing this doesn't do anything, but doesn't break anything either,
+		// and allows us to run the basic command test too.
+		if isLocal {
+			c.Ui.Error("Local state cannot be unlocked by another process")
+			return 1
+		}
+
+		desc := "Terraform will remove the lock on the remote state.\n" +
+			"This will allow local Terraform commands to modify this state, even though it\n" +
+			"may be still be in use. Only 'yes' will be accepted to confirm."
+
+		v, err := c.UIInput().Input(&terraform.InputOpts{
+			Id:          "force-unlock",
+			Query:       "Do you really want to force-unlock?",
+			Description: desc,
+		})
+		if err != nil {
+			c.Ui.Error(fmt.Sprintf("Error asking for confirmation: %s", err))
+			return 1
+		}
+		if v != "yes" {
+			c.Ui.Output("force-unlock cancelled.")
+			return 1
+		}
+	}
+
+	if err := s.Unlock(); err != nil {
+		c.Ui.Error(fmt.Sprintf("Failed to unlock state: %s", err))
+		return 1
+	}
+
+	c.Ui.Output(c.Colorize().Color(strings.TrimSpace(outputUnlockSuccess)))
+	return 0
+}
+
+func (c *UnlockCommand) Help() string {
+	helpText := `
+Usage: terraform force-unlock [DIR]
+
+  Manually unlock the state for the defined configuration.
+
+  This will not modify your infrastructure. This command removes the lock on the
+  state for the current configuration. The behavior of this lock is dependent
+  on the backend being used. Local state files cannot be unlocked by another
+  process.
+
+Options:
+
+  -force                 Don't ask for input for unlock confirmation.
+`
+	return strings.TrimSpace(helpText)
+}
+
+func (c *UnlockCommand) Synopsis() string {
+	return "Manually unlock the terraform state"
+}
+
+const outputUnlockSuccess = `
+[reset][bold][red]Terraform state has been successfully unlocked![reset][red]
+
+The state has been unlocked, and Terraform commands should now be able to
+obtain a new lock on the remote state.
+`

command/unlock_test.go

@@ -0,0 +1,46 @@
+package command
+
+import (
+	"os"
+	"testing"
+
+	"github.com/hashicorp/terraform/terraform"
+	"github.com/mitchellh/cli"
+)
+
+// Since we can't unlock a local state file, just test that calling unlock
+// doesn't fail.
+// TODO: mock remote state for UI testing
+func TestUnlock(t *testing.T) {
+	td := tempDir(t)
+	os.MkdirAll(td, 0755)
+	defer os.RemoveAll(td)
+	defer testChdir(t, td)()
+
+	// Write the legacy state
+	statePath := DefaultStateFilename
+	{
+		f, err := os.Create(statePath)
+		if err != nil {
+			t.Fatalf("err: %s", err)
+		}
+		err = terraform.WriteState(testState(), f)
+		f.Close()
+		if err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	p := testProvider()
+	ui := new(cli.MockUi)
+	c := &UnlockCommand{
+		Meta: Meta{
+			ContextOpts: testCtxConfig(p),
+			Ui:          ui,
+		},
+	}
+
+	if code := c.Run([]string{"-force"}); code != 0 {
+		t.Fatalf("bad: %d\n\n%s", code, ui.ErrorWriter.String())
+	}
+}

command/untaint_test.go

@@ -68,7 +68,7 @@ func TestUntaint_lockedState(t *testing.T) {
 		},
 	}
 	statePath := testStateFile(t, state)
-	unlock, err := testLockState(statePath)
+	unlock, err := testLockState("./testdata", statePath)
 	if err != nil {
 		t.Fatal(err)
 	}

commands.go

@@ -75,6 +75,12 @@ func init() {
 			}, nil
 		},
 
+		"force-unlock": func() (cli.Command, error) {
+			return &command.UnlockCommand{
+				Meta: meta,
+			}, nil
+		},
+
 		"get": func() (cli.Command, error) {
 			return &command.GetCommand{
 				Meta: meta,