Function makeClosureHandler

pkg/server/ui.go:340–358

makeClosureHandler returns a handler to serve Closure files. root is either: 1. empty: use the Closure files compiled in to the binary (if available), else redirect to the Internet. 2. a URL prefix: base of Perkeep to get Closure to redirect to 3. a path on disk to the root of camlistore's source (w

(root, handlerName string)

//  3. a path on disk to the root of camlistore's source (which
//     contains the necessary subset of Closure files)
func makeClosureHandler(root, handlerName string) (http.Handler, error) {
	// devcam server environment variable takes precedence:
	if d := os.Getenv("CAMLI_DEV_CLOSURE_DIR"); d != "" {
		log.Printf("%v: serving Closure from devcam server's $CAMLI_DEV_CLOSURE_DIR: %v", handlerName, d)
		return http.FileServer(http.Dir(d)), nil
	}
	if root == "" {
		fs := closurestatic.Closure
		log.Printf("%v: serving Closure from embedded resources", handlerName)
		return http.FileServer(http.FS(fs)), nil
	}
	if strings.HasPrefix(root, "http") {
		log.Printf("%v: serving Closure using redirects to %v", handlerName, root)
		return closureRedirector(root), nil
	}

	path := filepath.Join(vendorEmbed, "closure", "lib", "closure")
	return makeFileServer(root, path, filepath.Join("goog", "base.js"))
}

func makeFileServer(sourceRoot string, pathToServe string, expectedContentPath string) (http.Handler, error) {
	fi, err := os.Stat(sourceRoot)