Add initial distributor CLI skeleton

internal/cli/inspect.go

@@ -0,0 +1,36 @@
+package cli
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"gitea.maximumdirect.net/eric/distributor/internal/app"
+)
+
+func inspectCommand(ctx context.Context, args []string, stdout, stderr io.Writer) int {
+	if hasHelp(args) {
+		printInspectHelp(stdout)
+		return exitOK
+	}
+	if len(args) > 1 {
+		fmt.Fprintf(stderr, "%s: inspect accepts at most one path\n", app.Name)
+		return exitUsage
+	}
+	var path string
+	if len(args) == 1 {
+		path = args[0]
+	}
+	if err := app.Inspect(ctx, app.InspectOptions{Path: path}); err != nil {
+		return fail(stderr, err)
+	}
+	return exitOK
+}
+
+func printInspectHelp(w io.Writer) {
+	fmt.Fprint(w, `Usage:
+  distributor inspect <path>
+
+The inspect command is present but bundle inspection is not implemented yet.
+`)
+}

internal/cli/root.go

@@ -0,0 +1,84 @@
+package cli
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"strings"
+
+	"gitea.maximumdirect.net/eric/distributor/internal/app"
+)
+
+const (
+	exitOK    = 0
+	exitError = 1
+	exitUsage = 2
+)
+
+func Execute(ctx context.Context, args []string, stdout, stderr io.Writer) int {
+	if len(args) == 0 {
+		printRootHelp(stdout)
+		return exitOK
+	}
+
+	switch args[0] {
+	case "-h", "--help", "help":
+		printRootHelp(stdout)
+		return exitOK
+	case "version":
+		return versionCommand(ctx, args[1:], stdout, stderr)
+	case "run":
+		return runCommand(ctx, args[1:], stdout, stderr)
+	case "validate":
+		return validateCommand(ctx, args[1:], stdout, stderr)
+	case "inspect":
+		return inspectCommand(ctx, args[1:], stdout, stderr)
+	default:
+		fmt.Fprintf(stderr, "%s: unknown command %q\n\n", app.Name, args[0])
+		printRootHelp(stderr)
+		return exitUsage
+	}
+}
+
+func printRootHelp(w io.Writer) {
+	fmt.Fprintf(w, `%s validates and publishes manifested report bundles.
+
+Usage:
+  %s <command> [options]
+
+Commands:
+  version    Print version information
+  run        Run configured distribution pipelines
+  validate   Validate a source bundle or bundle tree
+  inspect    Inspect bundles or distributor state
+
+Use "%s <command> --help" for command-specific help.
+`, app.Name, app.Name, app.Name)
+}
+
+func hasHelp(args []string) bool {
+	for _, arg := range args {
+		if arg == "-h" || arg == "--help" {
+			return true
+		}
+	}
+	return false
+}
+
+func fail(stderr io.Writer, err error) int {
+	if errors.Is(err, app.ErrNotImplemented) {
+		fmt.Fprintf(stderr, "%s: %s\n", app.Name, err)
+		return exitError
+	}
+	fmt.Fprintf(stderr, "%s: %s\n", app.Name, err)
+	return exitError
+}
+
+func rejectExtraArgs(stderr io.Writer, command string, args []string) bool {
+	if len(args) == 0 {
+		return false
+	}
+	fmt.Fprintf(stderr, "%s: %s does not accept arguments: %s\n", app.Name, command, strings.Join(args, " "))
+	return true
+}

internal/cli/root_test.go

@@ -0,0 +1,75 @@
+package cli
+
+import (
+	"bytes"
+	"context"
+	"strings"
+	"testing"
+)
+
+func TestExecuteRootHelp(t *testing.T) {
+	var stdout, stderr bytes.Buffer
+
+	code := Execute(context.Background(), []string{"--help"}, &stdout, &stderr)
+
+	if code != exitOK {
+		t.Fatalf("exit code = %d, want %d", code, exitOK)
+	}
+	if !strings.Contains(stdout.String(), "Usage:") {
+		t.Fatalf("stdout = %q, want help text", stdout.String())
+	}
+	if stderr.Len() != 0 {
+		t.Fatalf("stderr = %q, want empty", stderr.String())
+	}
+}
+
+func TestExecuteVersion(t *testing.T) {
+	var stdout, stderr bytes.Buffer
+
+	code := Execute(context.Background(), []string{"version"}, &stdout, &stderr)
+
+	if code != exitOK {
+		t.Fatalf("exit code = %d, want %d", code, exitOK)
+	}
+	if got, want := stdout.String(), "distributor dev\n"; got != want {
+		t.Fatalf("stdout = %q, want %q", got, want)
+	}
+	if stderr.Len() != 0 {
+		t.Fatalf("stderr = %q, want empty", stderr.String())
+	}
+}
+
+func TestPlaceholderCommandsFailClearly(t *testing.T) {
+	tests := []string{"run", "validate", "inspect"}
+
+	for _, command := range tests {
+		t.Run(command, func(t *testing.T) {
+			var stdout, stderr bytes.Buffer
+
+			code := Execute(context.Background(), []string{command}, &stdout, &stderr)
+
+			if code != exitError {
+				t.Fatalf("exit code = %d, want %d", code, exitError)
+			}
+			if stdout.Len() != 0 {
+				t.Fatalf("stdout = %q, want empty", stdout.String())
+			}
+			if !strings.Contains(stderr.String(), "not implemented") {
+				t.Fatalf("stderr = %q, want not implemented error", stderr.String())
+			}
+		})
+	}
+}
+
+func TestUnknownCommandIsUsageError(t *testing.T) {
+	var stdout, stderr bytes.Buffer
+
+	code := Execute(context.Background(), []string{"nope"}, &stdout, &stderr)
+
+	if code != exitUsage {
+		t.Fatalf("exit code = %d, want %d", code, exitUsage)
+	}
+	if !strings.Contains(stderr.String(), "unknown command") {
+		t.Fatalf("stderr = %q, want unknown command error", stderr.String())
+	}
+}

internal/cli/run.go

@@ -0,0 +1,32 @@
+package cli
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"gitea.maximumdirect.net/eric/distributor/internal/app"
+)
+
+func runCommand(ctx context.Context, args []string, stdout, stderr io.Writer) int {
+	if hasHelp(args) {
+		printRunHelp(stdout)
+		return exitOK
+	}
+	if len(args) > 0 {
+		fmt.Fprintf(stderr, "%s: run does not accept options yet: %v\n", app.Name, args)
+		return exitUsage
+	}
+	if err := app.Run(ctx, app.RunOptions{}); err != nil {
+		return fail(stderr, err)
+	}
+	return exitOK
+}
+
+func printRunHelp(w io.Writer) {
+	fmt.Fprint(w, `Usage:
+  distributor run
+
+The run command is present but distribution behavior is not implemented yet.
+`)
+}

internal/cli/validate.go

@@ -0,0 +1,36 @@
+package cli
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"gitea.maximumdirect.net/eric/distributor/internal/app"
+)
+
+func validateCommand(ctx context.Context, args []string, stdout, stderr io.Writer) int {
+	if hasHelp(args) {
+		printValidateHelp(stdout)
+		return exitOK
+	}
+	if len(args) > 1 {
+		fmt.Fprintf(stderr, "%s: validate accepts at most one path\n", app.Name)
+		return exitUsage
+	}
+	var path string
+	if len(args) == 1 {
+		path = args[0]
+	}
+	if err := app.Validate(ctx, app.ValidateOptions{Path: path}); err != nil {
+		return fail(stderr, err)
+	}
+	return exitOK
+}
+
+func printValidateHelp(w io.Writer) {
+	fmt.Fprint(w, `Usage:
+  distributor validate <path>
+
+The validate command is present but bundle validation is not implemented yet.
+`)
+}

internal/cli/version.go

@@ -0,0 +1,29 @@
+package cli
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"gitea.maximumdirect.net/eric/distributor/internal/app"
+)
+
+func versionCommand(_ context.Context, args []string, stdout, stderr io.Writer) int {
+	if hasHelp(args) {
+		printVersionHelp(stdout)
+		return exitOK
+	}
+	if rejectExtraArgs(stderr, "version", args) {
+		return exitUsage
+	}
+	fmt.Fprintln(stdout, app.VersionString())
+	return exitOK
+}
+
+func printVersionHelp(w io.Writer) {
+	fmt.Fprint(w, `Usage:
+  distributor version
+
+Print version information.
+`)
+}