[terraform] add init options -reconfigure and -migrate-state

modules/terraform/init.go

@@ -18,6 +18,16 @@ func Init(t testing.TestingT, options *Options) string {
 // InitE calls terraform init and return stdout/stderr.
 func InitE(t testing.TestingT, options *Options) (string, error) {
 	args := []string{"init", fmt.Sprintf("-upgrade=%t", options.Upgrade)}
+
+	// Append reconfigure option if specified
+	if options.Reconfigure {
+		args = append(args, "-reconfigure")
+	}
+	// Append combination of migrate-state and force-copy to suppress answer prompt
+	if options.MigrateState {
+		args = append(args, "-migrate-state", "-force-copy")
+	}
+
 	args = append(args, FormatTerraformBackendConfigAsArgs(options.BackendConfig)...)
 	args = append(args, FormatTerraformPluginDirAsArgs(options.PluginDir)...)
 	return RunTerraformCommandE(t, options, args...)

modules/terraform/init_test.go

@@ -82,3 +82,71 @@ func TestInitPluginDir(t *testing.T) {
 
 	assert.Contains(t, initOutput, "(unauthenticated)")
 }
+
+func TestInitReconfigureBackend(t *testing.T) {
+	t.Parallel()
+
+	stateDirectory, err := ioutil.TempDir("", t.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(stateDirectory)
+
+	testFolder, err := files.CopyTerraformFolderToTemp("../../test/fixtures/terraform-backend", t.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(testFolder)
+
+	options := &Options{
+		TerraformDir: testFolder,
+		BackendConfig: map[string]interface{}{
+			"path": filepath.Join(stateDirectory, "backend.tfstate"),
+			"workspace_dir": "current",
+		},
+	}
+
+	Init(t, options)
+
+	options.BackendConfig["workspace_dir"] = "new"
+	_, err = InitE(t, options)
+	assert.Error(t, err, "Backend initialization with changed configuration should fail without -reconfigure option")
+
+	options.Reconfigure = true
+	_, err = InitE(t, options)
+	assert.NoError(t, err, "Backend initialization with changed configuration should success with -reconfigure option")
+}
+
+func TestInitBackendMigration(t *testing.T) {
+	t.Parallel()
+
+	stateDirectory, err := ioutil.TempDir("", t.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(stateDirectory)
+
+	testFolder, err := files.CopyTerraformFolderToTemp("../../test/fixtures/terraform-backend", t.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(testFolder)
+
+	options := &Options{
+		TerraformDir: testFolder,
+		BackendConfig: map[string]interface{}{
+			"path": filepath.Join(stateDirectory, "backend.tfstate"),
+			"workspace_dir": "current",
+		},
+	}
+
+	Init(t, options)
+
+	options.BackendConfig["workspace_dir"] = "new"
+	_, err = InitE(t, options)
+	assert.Error(t, err, "Backend initialization with changed configuration should fail without -migrate-state option")
+
+	options.MigrateState = true
+	_, err = InitE(t, options)
+	assert.NoError(t, err, "Backend initialization with changed configuration should success with -migrate-state option")
+}

modules/terraform/options.go

@@ -60,6 +60,8 @@ type Options struct {
 	MaxRetries               int                    // Maximum number of times to retry errors matching RetryableTerraformErrors
 	TimeBetweenRetries       time.Duration          // The amount of time to wait between retries
 	Upgrade                  bool                   // Whether the -upgrade flag of the terraform init command should be set to true or not
+	Reconfigure              bool                   // Set the -reconfigure flag to the terraform init command
+	MigrateState             bool                   // Set the -migrate-state and -force-copy (suppress 'yes' answer prompt) flag to the terraform init command
 	NoColor                  bool                   // Whether the -no-color flag will be set for any Terraform command or not
 	SshAgent                 *ssh.SshAgent          // Overrides local SSH agent with the given in-process agent
 	NoStderr                 bool                   // Disable stderr redirection