FEAT: Add backend template (#2)

* feat: embed backend

* fix: versioned router

* fix: rearrange packages

* fix: make writing concurrent

Author: jgfranco17

cli/command/cmds/build.go

@@ -85,7 +85,7 @@ func (c *buildCommand) invoke() *cobra.Command {
 			if err != nil {
 				return &errorhandling.CommandError{
 					Err:      fmt.Errorf("failed to load template resources for category %q: %w", category, err),
-					ExitCode: errorhandling.ExitGenericError,
+					ExitCode: errorhandling.ExitTemplateError,
 					HelpText: "Failed to load template resources. Please check the category name and try again.",
 				}
 			}
@@ -107,10 +107,11 @@ func (c *buildCommand) invoke() *cobra.Command {
 			if err := templater.Render(ctx, c.outputPath); err != nil {
 				return &errorhandling.CommandError{
 					Err:      fmt.Errorf("failed to render template %q: %w", category, err),
-					ExitCode: errorhandling.ExitGenericError,
+					ExitCode: errorhandling.ExitTemplateError,
 					HelpText: "Please check the template and try again.",
 				}
 			}
+
 			logger.WithFields(logrus.Fields{
 				"category": category,
 				"output":   c.outputPath,

cli/command/cmds/build_test.go

@@ -89,7 +89,7 @@ func TestBuildCommand(t *testing.T) {
 				return newTestBuildCommand(errorLoader, nil)
 			},
 			wantErr:  true,
-			wantExit: errorhandling.ExitGenericError,
+			wantExit: errorhandling.ExitTemplateError,
 		},
 		{
 			name: "renderer failure returns generic error",
@@ -100,7 +100,7 @@ func TestBuildCommand(t *testing.T) {
 				return newTestBuildCommand(successLoader, errors.New("render failure"))
 			},
 			wantErr:  true,
-			wantExit: errorhandling.ExitGenericError,
+			wantExit: errorhandling.ExitTemplateError,
 		},
 		{
 			name: "successful render on empty dir prints success message",

cli/entrypoint/entrypoint.go

@@ -51,7 +51,7 @@ func Run(metadata []byte) {
 	})
 	if err != nil {
 		printError("Error creating command: %v", err)
-		os.Exit(errorhandling.ExitGenericError.Int())
+		os.Exit(errorhandling.ExitRuntimeError.Int())
 	}
 
 	var exitCode int
@@ -71,7 +71,7 @@ func handlerExecError(err error) int {
 		return cmdErr.ExitCode.Int()
 	}
 	fmt.Printf("An unexpected error occurred: %v\n", err)
-	return errorhandling.ExitGenericError.Int()
+	return errorhandling.ExitRuntimeError.Int()
 }
 
 func printError(format string, args ...any) {

cli/internal/errorhandling/errors.go

@@ -15,7 +15,7 @@ func (e ExitCode) Int() int {
 
 const (
 	ExitSuccess       ExitCode = 0
-	ExitGenericError  ExitCode = 1
+	ExitRuntimeError  ExitCode = 1
 	ExitPanicError    ExitCode = 2
 	ExitTemplateError ExitCode = 3
 	ExitInputError    ExitCode = 4

cli/internal/errorhandling/errors_test.go

@@ -11,7 +11,7 @@ import (
 func TestCommandError(t *testing.T) {
 	mockErr := CommandError{
 		Err:      errors.New("mock error"),
-		ExitCode: ExitGenericError,
+		ExitCode: ExitRuntimeError,
 		HelpText: "This is some help text.",
 	}
 

cli/internal/templating/embed.go

@@ -11,7 +11,7 @@ import (
 	"github.com/jgfranco17/hackstack/cli/internal/logging"
 )
 
-//go:embed resources
+//go:embed all:resources
 var embeddedResources embed.FS
 
 // CLIProject holds the variables required to render the CLI project templates.
@@ -41,10 +41,22 @@ func (d *CLIProject) Validate() error {
 	return nil
 }
 
+// Load retrieves the embedded template files for the specified category and returns
+// them as an fs.FS instance for use in rendering. The category must be one of the
+// currently-supported categories.
 func Load(ctx context.Context, category string) (fs.FS, error) {
 	logger := logging.FromContext(ctx).WithField("module", "templating")
 
+	allowedCategories := map[string]bool{
+		"backend": true,
+		"cli":     true,
+	}
+
 	category = strings.ToLower(category)
+	if _, ok := allowedCategories[category]; !ok {
+		return nil, fmt.Errorf("invalid templating category %q", category)
+	}
+
 	subDirPath := filepath.Join("resources", category)
 	sub, err := fs.Sub(embeddedResources, subDirPath)
 	if err != nil {

cli/internal/templating/embed_test.go

@@ -67,16 +67,43 @@ func TestCLIProject_Validate(t *testing.T) {
 }
 
 func TestLoad_ValidCategory(t *testing.T) {
+	testCases := []struct {
+		name     string
+		category string
+		invalid  bool
+	}{
+		{name: "backend category", category: "backend"},
+		{name: "cli category", category: "cli"},
+		{name: "category case insensitivity", category: "CLI"},
+		{name: "invalid category", category: "unknown", invalid: true},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			ctx := testContext(t)
+			sub, err := Load(ctx, tc.category)
+
+			if tc.invalid {
+				require.Error(t, err)
+				assert.ErrorContains(t, err, "invalid templating category")
+			} else {
+				require.NoError(t, err)
+				require.NotNil(t, sub)
+
+				entries, err := fs.ReadDir(sub, ".")
+				require.NoError(t, err)
+				assert.NotEmpty(t, entries)
+			}
+		})
+	}
+}
+
+func TestLoad_InvalidCategory(t *testing.T) {
 	ctx := testContext(t)
-	sub, err := Load(ctx, "cli")
 
-	require.NoError(t, err)
-	require.NotNil(t, sub)
+	_, err := Load(ctx, "unknown")
 
-	// Confirm the returned FS is non-empty.
-	entries, err := fs.ReadDir(sub, ".")
-	require.NoError(t, err)
-	assert.NotEmpty(t, entries, "loaded FS should contain template files")
+	require.Error(t, err)
+	assert.Contains(t, err.Error(), `invalid templating category "unknown"`)
 }
 
 func TestLoad_CategoryIsCaseInsensitive(t *testing.T) {

cli/internal/templating/engine.go

@@ -7,9 +7,11 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"sync/atomic"
 	"text/template"
 
-	"github.com/jgfranco17/hackstack/cli/internal/errorhandling"
+	"golang.org/x/sync/errgroup"
+
 	"github.com/jgfranco17/hackstack/cli/internal/fileutils"
 	"github.com/jgfranco17/hackstack/cli/internal/logging"
 )
@@ -29,7 +31,9 @@ func NewEngine(files fs.FS, data CLIProject) *Engine {
 func (e *Engine) Render(ctx context.Context, outputPath string) error {
 	logger := logging.FromContext(ctx).WithField("module", "templating")
 
-	count := 0
+	var count atomic.Int64
+	g, ctx := errgroup.WithContext(ctx)
+
 	walker := func(path string, d fs.DirEntry, err error) error {
 		if err != nil {
 			return fmt.Errorf("walk error at %q: %w", path, err)
@@ -40,30 +44,38 @@ func (e *Engine) Render(ctx context.Context, outputPath string) error {
 
 		destPath := filepath.Join(outputPath, filepath.FromSlash(path))
 
+		var work func() error
 		switch {
 		case strings.HasSuffix(path, ".j2"):
 			destPath = strings.TrimSuffix(destPath, ".j2")
-			logger.WithField("file", path).Trace("Rendering from template")
-			count++
-			return renderTemplate(e.Files, path, destPath, e.Data)
+			work = func() error {
+				logger.WithField("file", path).Trace("Rendering from template")
+				return renderTemplate(e.Files, path, destPath, e.Data)
+			}
 		case strings.HasSuffix(path, ".copy"):
 			destPath = strings.TrimSuffix(destPath, ".copy")
-			logger.WithField("file", path).Trace("Copying file")
-			count++
-			return fileutils.CopyFile(e.Files, path, destPath)
+			work = func() error {
+				logger.WithField("file", path).Trace("Copying file")
+				return fileutils.CopyFile(e.Files, path, destPath)
+			}
 		default:
-			return fmt.Errorf("unrecognized resource extension for %q: expected .j2 or .copy", path)
+			return fmt.Errorf("unrecognized resource extension for %q", path)
 		}
+
+		count.Add(1)
+		g.Go(work)
+		return nil
 	}
 
 	if err := fs.WalkDir(e.Files, ".", walker); err != nil {
-		return &errorhandling.CommandError{
-			Err:      fmt.Errorf("failed to render templates: %w", err),
-			ExitCode: errorhandling.ExitTemplateError,
-			HelpText: "Check template resources and verify the contents.",
-		}
+		return fmt.Errorf("failed to render templates: %w", err)
 	}
-	logger.WithField("fileCount", count).Debug("Completed render")
+
+	if err := g.Wait(); err != nil {
+		return fmt.Errorf("failed to render templates: %w", err)
+	}
+
+	logger.WithField("fileCount", count.Load()).Debug("Completed render")
 	return nil
 }
 

cli/internal/templating/resources/backend/.github/actions/setup-workspace/action.yaml.copy

@@ -0,0 +1,19 @@
+---
+name: "Setup Go Workspace"
+description: "Configure Go and prepare the workspace"
+
+runs:
+  using: composite
+  steps:
+    - name: Set up Golang
+      uses: actions/setup-go@v5
+      with:
+        cache: false
+
+    - name: Install Just
+      uses: extractions/setup-just@v2
+
+    - name: Install Go modules
+      shell: bash
+      run: |
+        go mod tidy

cli/internal/templating/resources/backend/.github/workflows/compliance.yaml.copy

@@ -0,0 +1,36 @@
+---
+name: Compliance Checks
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  lint:
+    name: Run linters
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v5
+
+      - name: Setup workspace
+        uses: ./.github/actions/setup-workspace
+
+      - name: Install linters
+        run: |
+          pip install --upgrade pip
+          pip install pre-commit==3.5.0
+
+      - name: Install dependencies
+        run: |
+          just tidy
+          go install golang.org/x/tools/cmd/goimports@latest
+          go install github.com/fzipp/gocyclo/cmd/gocyclo@latest
+
+      - name: Lint
+        run: pre-commit run --all-files