add ShowStateFile, ShowPlanFile

tfexec/show.go

@@ -10,6 +10,8 @@ import (
 	tfjson "github.com/hashicorp/terraform-json"
 )
 
+// Show reads the default state path and outputs the state.
+// To read a state or plan file, ShowState or ShowPlan must be used instead.
 func (tf *Terraform) Show(ctx context.Context) (*tfjson.State, error) {
 	err := tf.compatible(ctx, tf0_12_0, nil)
 	if err != nil {
@@ -40,6 +42,77 @@ func (tf *Terraform) Show(ctx context.Context) (*tfjson.State, error) {
 	return &ret, nil
 }
 
+// ShowStateFile reads a given state file and outputs the state.
+func (tf *Terraform) ShowStateFile(ctx context.Context, statePath string) (*tfjson.State, error) {
+	err := tf.compatible(ctx, tf0_12_0, nil)
+	if err != nil {
+		return nil, fmt.Errorf("terraform show -json was added in 0.12.0: %w", err)
+	}
+
+	if statePath == "" {
+		return nil, fmt.Errorf("statePath cannot be blank: use Show() if not passing statePath")
+	}
+
+	showCmd := tf.showCmd(ctx, statePath)
+
+	var ret tfjson.State
+	var outBuf bytes.Buffer
+	showCmd.Stdout = &outBuf
+
+	err = tf.runTerraformCmd(showCmd)
+	if err != nil {
+		return nil, err
+	}
+
+	err = json.Unmarshal(outBuf.Bytes(), &ret)
+	if err != nil {
+		return nil, err
+	}
+
+	err = ret.Validate()
+	if err != nil {
+		return nil, err
+	}
+
+	return &ret, nil
+}
+
+// ShowPlanFile reads a given plan file and outputs the plan.
+func (tf *Terraform) ShowPlanFile(ctx context.Context, planPath string) (*tfjson.Plan, error) {
+	err := tf.compatible(ctx, tf0_12_0, nil)
+	if err != nil {
+		return nil, fmt.Errorf("terraform show -json was added in 0.12.0: %w", err)
+	}
+
+	if planPath == "" {
+		return nil, fmt.Errorf("planPath cannot be blank: use Show() if not passing planPath")
+	}
+
+	showCmd := tf.showCmd(ctx, planPath)
+
+	var ret tfjson.Plan
+	var outBuf bytes.Buffer
+	showCmd.Stdout = &outBuf
+
+	err = tf.runTerraformCmd(showCmd)
+	if err != nil {
+		return nil, err
+	}
+
+	err = json.Unmarshal(outBuf.Bytes(), &ret)
+	if err != nil {
+		return nil, err
+	}
+
+	err = ret.Validate()
+	if err != nil {
+		return nil, err
+	}
+
+	return &ret, nil
+
+}
+
 func (tf *Terraform) showCmd(ctx context.Context, args ...string) *exec.Cmd {
 	allArgs := []string{"show", "-json", "-no-color"}
 	allArgs = append(allArgs, args...)

tfexec/show_test.go

@@ -29,3 +29,47 @@ func TestShowCmd(t *testing.T) {
 		"-no-color",
 	}, nil, showCmd)
 }
+
+func TestShowStateFileCmd(t *testing.T) {
+	td := testTempDir(t)
+	defer os.RemoveAll(td)
+
+	tf, err := NewTerraform(td, tfVersion(t, testutil.Latest012))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// empty env, to avoid environ mismatch in testing
+	tf.SetEnv(map[string]string{})
+
+	showCmd := tf.showCmd(context.Background(), "statefilepath")
+
+	assertCmd(t, []string{
+		"show",
+		"-json",
+		"-no-color",
+		"statefilepath",
+	}, nil, showCmd)
+}
+
+func TestShowPlanFileCmd(t *testing.T) {
+	td := testTempDir(t)
+	defer os.RemoveAll(td)
+
+	tf, err := NewTerraform(td, tfVersion(t, testutil.Latest012))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// empty env, to avoid environ mismatch in testing
+	tf.SetEnv(map[string]string{})
+
+	showCmd := tf.showCmd(context.Background(), "planfilepath")
+
+	assertCmd(t, []string{
+		"show",
+		"-json",
+		"-no-color",
+		"planfilepath",
+	}, nil, showCmd)
+}