feat: storybook, reduced need for rebuild.

go.mod

@@ -16,6 +16,7 @@ require (
 	go.uber.org/atomic v1.8.0 // indirect
 	go.uber.org/multierr v1.7.0 // indirect
 	go.uber.org/zap v1.17.0
+	golang.org/x/mod v0.5.1 // indirect
 )
 
 //replace github.com/a-h/lexical => /Users/adrian/github.com/a-h/lexical

go.sum

@@ -56,15 +56,28 @@ go.uber.org/multierr v1.7.0 h1:zaiO/rmgFjbmCXdSYJWQcdvOCsthmdaHfr3Gm2Kx4Ec=
 go.uber.org/multierr v1.7.0/go.mod h1:7EAYxJLBy9rStEaz58O2t4Uvip6FSURkq8/ppBp95ak=
 go.uber.org/zap v1.17.0 h1:MTjgFu6ZLKvY6Pvaqk97GlxNBuMpV4Hy/3P6tRGlI2U=
 go.uber.org/zap v1.17.0/go.mod h1:MXVU+bhUf/A7Xi2HNOnopQOrmycQ5Ih87HtOu4q5SSo=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/mod v0.5.1 h1:OJxoQ/rynoF0dcCdI7cLPktw/hR2cueqYfjm43oqK38=
+golang.org/x/mod v0.5.1/go.mod h1:5OXOZSfqPIIbmVBIIKWRFfZjPR0E5r58TLhUjH0a2Ro=
 golang.org/x/net v0.0.0-20180218175443-cbe0f9307d01/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20210614182718-04defd469f4e h1:XpT3nA5TvE525Ne3hInMh6+GETgn27Zfm9dxsThnX2Q=
 golang.org/x/net v0.0.0-20210614182718-04defd469f4e/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

storybook/storybook.go

@@ -12,8 +12,11 @@ import (
 	"path"
 	"reflect"
 	"strconv"
+	"strings"
 	"sync"
 
+	"golang.org/x/mod/sumdb/dirhash"
+
 	"github.com/a-h/pathvars"
 	"github.com/a-h/templ"
 	"github.com/rs/cors"
@@ -45,7 +48,7 @@ func New() *Storybook {
 		Log:       logger,
 	}
 	sh.Server = http.Server{
-		Handler: sh,
+		Handler: http.NotFoundHandler(),
 		Addr:    "localhost:60606",
 	}
 	return sh
@@ -62,32 +65,10 @@ func (sh *Storybook) AddComponent(name string, componentConstructor interface{},
 
 var storybookPreviewMatcher = pathvars.NewExtractor("/storybook_preview/{name}")
 
-func (sh *Storybook) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-	values, ok := storybookPreviewMatcher.Extract(r.URL)
-	if !ok {
-		sh.Log.Info("URL not matched", zap.String("url", r.URL.String()))
-		http.NotFound(w, r)
-		return
-	}
-	name, ok := values["name"]
-	if !ok {
-		sh.Log.Info("URL does not contain component name", zap.String("url", r.URL.String()))
-		http.NotFound(w, r)
-		return
-	}
-	h, found := sh.Handlers[name]
-	if !found {
-		sh.Log.Info("Component name not found", zap.String("name", name), zap.String("url", r.URL.String()))
-		http.NotFound(w, r)
-		return
-	}
-	cors.Default().Handler(h).ServeHTTP(w, r)
-}
-
 func (sh *Storybook) ListenAndServeWithContext(ctx context.Context) (err error) {
 	defer sh.Log.Sync()
 	// Download Storybook to the directory required.
-	sh.Log.Info("Installing storybook")
+	sh.Log.Info("Installing storybook.")
 	err = sh.installStorybook()
 	if err != nil {
 		return
@@ -97,25 +78,39 @@ func (sh *Storybook) ListenAndServeWithContext(ctx context.Context) (err error)
 	}
 
 	// Copy the config to Storybook.
-	sh.Log.Info("Configuring storybook")
-	err = sh.configureStorybook()
+	sh.Log.Info("Configuring storybook.")
+	configHasChanged, err := sh.configureStorybook()
 	if err != nil {
 		return
 	}
 	if ctx.Err() != nil {
 		return
 	}
 
-	// Run storybook.
-	go func() {
-		sh.Log.Info("Starting Storybook on http://localhost:6006/")
-		sh.runStorybook(ctx)
-	}()
+	// Execute a static build of storybook if the config has changed.
+	if configHasChanged {
+		sh.Log.Info("Config not present, or has changed, rebuilding storybook.")
+		sh.buildStorybook()
+	} else {
+		sh.Log.Info("Storybook is up-to-date, skipping build step.")
+	}
+	if ctx.Err() != nil {
+		return
+	}
+
+	// Combine static and dynamic routes and start the server.
+	staticHandler := http.FileServer(http.Dir("./storybook-server/storybook-static"))
+	sbh := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if strings.HasPrefix(r.URL.Path, "/storybook_preview/") {
+			sh.previewHandler(w, r)
+			return
+		}
+		staticHandler.ServeHTTP(w, r)
+	})
+	sh.Server.Handler = cors.Default().Handler(sbh)
 
-	// Start the Go server.
-	sh.Server.Handler = sh
 	go func() {
-		sh.Log.Info("Starting Go server", zap.String("address", sh.Server.Addr), zap.String("serverUrl", sh.ServerURL))
+		sh.Log.Info("Starting Go server", zap.String("address", sh.Server.Addr), zap.String("url", fmt.Sprintf("http://%s", sh.Server.Addr)), zap.String("previewUrl", sh.ServerURL))
 		err = sh.Server.ListenAndServe()
 	}()
 	<-ctx.Done()
@@ -124,10 +119,32 @@ func (sh *Storybook) ListenAndServeWithContext(ctx context.Context) (err error)
 	return err
 }
 
+func (sh *Storybook) previewHandler(w http.ResponseWriter, r *http.Request) {
+	values, ok := storybookPreviewMatcher.Extract(r.URL)
+	if !ok {
+		sh.Log.Info("URL not matched", zap.String("url", r.URL.String()))
+		http.NotFound(w, r)
+		return
+	}
+	name, ok := values["name"]
+	if !ok {
+		sh.Log.Info("URL does not contain component name", zap.String("url", r.URL.String()))
+		http.NotFound(w, r)
+		return
+	}
+	h, found := sh.Handlers[name]
+	if !found {
+		sh.Log.Info("Component name not found", zap.String("name", name), zap.String("url", r.URL.String()))
+		http.NotFound(w, r)
+		return
+	}
+	h.ServeHTTP(w, r)
+}
+
 func (sh *Storybook) installStorybook() (err error) {
 	_, err = os.Stat(sh.Path)
 	if err == nil {
-		sh.Log.Info("Skipping installation - Storybook is already installed.")
+		sh.Log.Info("Storybook already installed, Skipping installation.")
 		return
 	}
 	if os.IsNotExist(err) {
@@ -148,38 +165,58 @@ func (sh *Storybook) installStorybook() (err error) {
 	return cmd.Run()
 }
 
-func (sh *Storybook) configureStorybook() error {
+func (sh *Storybook) configureStorybook() (configHasChanged bool, err error) {
 	// Delete template/existing files in the stories directory.
 	storiesDir := path.Join(sh.Path, "stories")
-	if err := os.RemoveAll(storiesDir); err != nil {
-		return err
+	before, err := dirhash.HashDir(storiesDir, "/", dirhash.DefaultHash)
+	if err != nil && !os.IsNotExist(err) {
+		return configHasChanged, err
+	}
+	if err = os.RemoveAll(storiesDir); err != nil {
+		return configHasChanged, err
 	}
 	if err := os.Mkdir(storiesDir, os.ModePerm); err != nil {
-		return err
+		return configHasChanged, err
 	}
 	// Create new *.stories.json files.
 	for _, c := range sh.Config {
 		name := path.Join(sh.Path, fmt.Sprintf("stories/%s.stories.json", c.Title))
 		f, err := os.Create(name)
 		if err != nil {
-			return fmt.Errorf("failed to create config file to %q: %w", name, err)
+			return configHasChanged, fmt.Errorf("failed to create config file to %q: %w", name, err)
 		}
 		err = json.NewEncoder(f).Encode(c)
 		if err != nil {
-			return fmt.Errorf("failed to write JSON config to %q: %w", name, err)
+			return configHasChanged, fmt.Errorf("failed to write JSON config to %q: %w", name, err)
 		}
 	}
+	after, err := dirhash.HashDir(storiesDir, "/", dirhash.DefaultHash)
+	configHasChanged = before != after
 	// Configure storybook Preview URL.
 	previewJS := fmt.Sprintf(`export const parameters = { server: { url: %s } };`, jsonEncode(sh.ServerURL))
-	return os.WriteFile(path.Join(sh.Path, ".storybook/preview.js"), []byte(previewJS), os.ModePerm)
+	err = os.WriteFile(path.Join(sh.Path, ".storybook/preview.js"), []byte(previewJS), os.ModePerm)
+	return
 }
 
 func jsonEncode(s string) string {
 	b, _ := json.Marshal(s)
 	return string(b)
 }
 
-func (sh *Storybook) runStorybook(ctx context.Context) (err error) {
+func (sh *Storybook) hasConfigChanged() (err error) {
+	var cmd exec.Cmd
+	cmd.Dir = sh.Path
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.Path, err = exec.LookPath("npm")
+	if err != nil {
+		return fmt.Errorf("templ-storybook: cannot run storybook, cannot find npm on the path, check that Node.js is installed: %w", err)
+	}
+	cmd.Args = []string{"npm", "run", "storybook-build"}
+	return cmd.Run()
+}
+
+func (sh *Storybook) buildStorybook() (err error) {
 	var cmd exec.Cmd
 	cmd.Dir = sh.Path
 	cmd.Stdout = os.Stdout
@@ -188,7 +225,7 @@ func (sh *Storybook) runStorybook(ctx context.Context) (err error) {
 	if err != nil {
 		return fmt.Errorf("templ-storybook: cannot run storybook, cannot find npm on the path, check that Node.js is installed: %w", err)
 	}
-	cmd.Args = []string{"npm", "run", "storybook"}
+	cmd.Args = []string{"npm", "run", "build-storybook"}
 	return cmd.Run()
 }