fix: update ftl Go module when building

This updates the go.mod file at the root of a Go FTL module.

FTL.code-workspace

@@ -0,0 +1,45 @@
+{
+	"folders": [
+		{
+			"path": "."
+		},
+		{
+			"path": "go-runtime"
+		},
+		{
+			"path": "kotlin-runtime"
+		},
+		{
+			"path": "examples/time"
+		},
+		{
+			"path": "examples/echo"
+		},
+		{
+			"path": "examples/online-boutique"
+		},
+		{
+			"path": "backend"
+		},
+		{
+			"path": "cmd/ftl",
+			"name": "cmd/ftl"
+		}
+	],
+	"settings": {
+		"files.exclude": {
+			"**/.git": true,
+			"**/.svn": true,
+			"**/.hg": true,
+			"**/CVS": true,
+			"**/.DS_Store": true,
+			"**/Thumbs.db": true,
+			"**/_ftl": true,
+			"**/node_modules": true,
+			"**/go.work": true,
+			"**/go.work.sum": true,
+			".hermit": true,
+			"**/*.zip": true,
+		}
+	}
+}

cmd/ftl/cmd_dev.go

@@ -13,7 +13,6 @@ import (
 
 	"github.com/bmatcuk/doublestar/v4"
 
-	"github.com/TBD54566975/ftl/backend/common/exec"
 	"github.com/TBD54566975/ftl/backend/common/log"
 	"github.com/TBD54566975/ftl/backend/common/moduleconfig"
 	"github.com/TBD54566975/ftl/protos/xyz/block/ftl/v1/ftlv1connect"
@@ -246,9 +245,8 @@ func initGitIgnore(ctx context.Context, dir string) []string {
 	if err == nil {
 		ignore = append(ignore, loadGitIgnore(home)...)
 	}
-	gitRootBytes, err := exec.Capture(ctx, dir, "git", "rev-parse", "--show-toplevel")
-	if err == nil {
-		gitRoot := strings.TrimSpace(string(gitRootBytes))
+	gitRoot := gitRoot(ctx, dir)
+	if gitRoot != "" {
 		for current := dir; strings.HasPrefix(current, gitRoot); current = path.Dir(current) {
 			ignore = append(ignore, loadGitIgnore(current)...)
 		}

cmd/ftl/main.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"os/signal"
 	"runtime"
+	"strings"
 	"syscall"
 
 	"connectrpc.com/connect"
@@ -14,6 +15,7 @@ import (
 
 	"github.com/TBD54566975/ftl"
 	_ "github.com/TBD54566975/ftl/backend/common/automaxprocs" // Set GOMAXPROCS to match Linux container CPU quota.
+	"github.com/TBD54566975/ftl/backend/common/exec"
 	"github.com/TBD54566975/ftl/backend/common/log"
 	"github.com/TBD54566975/ftl/backend/common/rpc"
 	"github.com/TBD54566975/ftl/protos/xyz/block/ftl/v1/ftlv1connect"
@@ -98,3 +100,21 @@ func makeDialer[Client rpc.Pingable](newClient func(connect.HTTPClient, string,
 		return rpc.Dial(newClient, cli.Endpoint.String(), log.Error), nil
 	}
 }
+
+// gitRoot returns the root of the git repository containing dir, or empty string if dir is not in a git repository.
+//
+// If dir is empty, the current working directory is used.
+func gitRoot(ctx context.Context, dir string) string {
+	if dir == "" {
+		var err error
+		dir, err = os.Getwd()
+		if err != nil {
+			return ""
+		}
+	}
+	gitRootBytes, err := exec.Capture(ctx, dir, "git", "rev-parse", "--show-toplevel")
+	if err != nil {
+		return ""
+	}
+	return strings.TrimSpace(string(gitRootBytes))
+}

go-runtime/compile/build.go

@@ -14,6 +14,7 @@ import (
 	"golang.org/x/mod/modfile"
 	"google.golang.org/protobuf/proto"
 
+	"github.com/TBD54566975/ftl"
 	"github.com/TBD54566975/scaffolder"
 
 	"github.com/TBD54566975/ftl/backend/common/exec"
@@ -50,7 +51,7 @@ const buildDirName = "_ftl"
 
 // Build the given module.
 func Build(ctx context.Context, moduleDir string, sch *schema.Schema) error {
-	goModVersion, err := readGoModVersion(filepath.Join(moduleDir, "go.mod"))
+	goModVersion, err := updateGoModule(filepath.Join(moduleDir, "go.mod"))
 	if err != nil {
 		return err
 	}
@@ -197,7 +198,8 @@ func genType(module *schema.Module, t schema.Type) string {
 	panic(fmt.Sprintf("unsupported type %T", t))
 }
 
-func readGoModVersion(goModPath string) (string, error) {
+// Update go.mod file to include the FTL version.
+func updateGoModule(goModPath string) (version string, err error) {
 	goModBytes, err := os.ReadFile(goModPath)
 	if err != nil {
 		return "", fmt.Errorf("failed to read %s: %w", goModPath, err)
@@ -206,5 +208,14 @@ func readGoModVersion(goModPath string) (string, error) {
 	if err != nil {
 		return "", fmt.Errorf("failed to parse %s: %w", goModPath, err)
 	}
+	if ftl.IsRelease(ftl.Version) {
+		if err := goModfile.AddRequire("github.com/TBD54566975/ftl", ftl.Version); err != nil {
+			return "", fmt.Errorf("failed to add github.com/TBD54566975/ftl to %s: %w", goModPath, err)
+		}
+		goModBytes = modfile.Format(goModfile.Syntax)
+		if err := os.WriteFile(goModPath, goModBytes, 0600); err != nil {
+			return "", fmt.Errorf("failed to update %s: %w", goModPath, err)
+		}
+	}
 	return goModfile.Go.Version, nil
 }

version.go

@@ -1,5 +1,12 @@
 package ftl
 
+import "strings"
+
+// IsRelease returns true if the version is a release version.
+func IsRelease(v string) bool {
+	return v != "dev" && !strings.HasSuffix(v, "-dirty")
+}
+
 // Version of FTL binary (set by linker).
 var Version = "dev"