Merge pull request 'fix: accept empty Terraform state imports' (#17) from fix/empty-terraform-state-import into main

Reviewed-on: #17

internal/bootstrap/bootstrap.go

@@ -86,17 +86,39 @@ var runGitEnvironment = func(dir string, environment []string, args ...string) (
 
 var verifyTalosVMs = verifyConfiguredTalosVMs
 
-var terraformStateResources = func(terraformDir string, environment []string) ([]string, error) {
+var terraformStateResources = listTerraformStateResources
+
+var runTerraformStateList = func(terraformDir string, environment []string) ([]byte, []byte, error) {
 	command := exec.Command("terraform", "state", "list")
 	command.Dir = terraformDir
 	command.Env = append(os.Environ(), environment...)
-	state, err := command.Output()
+	var stdout, stderr bytes.Buffer
+	command.Stdout = &stdout
+	command.Stderr = &stderr
+	err := command.Run()
+	return stdout.Bytes(), stderr.Bytes(), err
+}
+
+func listTerraformStateResources(terraformDir string, environment []string) ([]string, error) {
+	state, stderr, err := runTerraformStateList(terraformDir, environment)
 	if err != nil {
+		if terraformNoStateFile(stderr) {
+			return nil, nil
+		}
 		return nil, fmt.Errorf("list Terraform state: %w", err)
 	}
 	return strings.Fields(string(state)), nil
 }
 
+func terraformNoStateFile(stderr []byte) bool {
+	for _, line := range strings.Split(string(stderr), "\n") {
+		if strings.TrimSpace(line) == "No state file was found!" {
+			return true
+		}
+	}
+	return false
+}
+
 var destroyTalosVMs = func(terraformDir string, environment []string) error {
 	return utils.RunCommandInDirEnv(terraformDir, environment, "terraform", "destroy", "-auto-approve", "-input=false", "-target=proxmox_virtual_environment_vm.vm")
 }

internal/bootstrap/bootstrap_test.go

@@ -911,6 +911,31 @@ func TestTerraformPlanPathIsAbsolute(t *testing.T) {
 	}
 }
 
+func TestTerraformStateResourcesAllowsNoStateFile(t *testing.T) {
+	original := runTerraformStateList
+	t.Cleanup(func() { runTerraformStateList = original })
+	runTerraformStateList = func(string, []string) ([]byte, []byte, error) {
+		return nil, []byte("No state file was found!\n"), errors.New("exit status 1")
+	}
+
+	resources, err := listTerraformStateResources("terraform", nil)
+	if err != nil || len(resources) != 0 {
+		t.Fatalf("no-state Terraform result = %q, %v; want empty resources and nil error", resources, err)
+	}
+}
+
+func TestTerraformStateResourcesRejectsUnexpectedStateError(t *testing.T) {
+	original := runTerraformStateList
+	t.Cleanup(func() { runTerraformStateList = original })
+	runTerraformStateList = func(string, []string) ([]byte, []byte, error) {
+		return nil, []byte("Error: failed to load backend\n"), errors.New("exit status 1")
+	}
+
+	if _, err := listTerraformStateResources("terraform", nil); err == nil || !strings.Contains(err.Error(), "list Terraform state") {
+		t.Fatalf("unexpected Terraform state error was accepted: %v", err)
+	}
+}
+
 func TestVerifyStateTalosVMsRejectsForeignAndMissingVMs(t *testing.T) {
 	cfg := config.Config{Talos: config.TalosConfig{Nodes: []config.TalosNode{{Name: "cp-01", ProxmoxNode: "pve", VMID: 100}, {Name: "worker-01", ProxmoxNode: "pve", VMID: 101}}}}
 	if err := verifyStateTalosVMs([]string{`proxmox_virtual_environment_vm.vm["cp-01"]`, `proxmox_virtual_environment_vm.vm["foreign"]`}, cfg, false); err == nil || !strings.Contains(err.Error(), "unconfigured") {