nsqadmin: new flag --dev-static-dir instead of debug build tag

avoid hard-coded ../../nsqadmin/static/build in debug build,
more flexible and obvious this way

apps/nsqadmin/main.go

@@ -30,6 +30,7 @@ func nsqadminFlagSet(opts *nsqadmin.Options) *flag.FlagSet {
 
 	flagSet.String("http-address", opts.HTTPAddress, "<addr>:<port> to listen on for HTTP clients")
 	flagSet.String("base-path", opts.BasePath, "URL base path")
+	flagSet.String("dev-static-dir", opts.DevStaticDir, "(development use only)")
 
 	flagSet.String("graphite-url", opts.GraphiteURL, "graphite HTTP address")
 	flagSet.Bool("proxy-graphite", false, "proxy HTTP requests to graphite")

nsqadmin/README.md

@@ -11,14 +11,16 @@ Read the [docs](https://nsq.io/components/nsqadmin.html)
 ### Dependencies
 
  1. Install NodeJS 16.x (includes `npm`)
+ 2. Install [`go-bindata`](https://github.com/shuLhan/go-bindata) (for "legacy" go < 1.16)
 
 ### Live Reload Workflow
 
  1. `$ npm install`
  2. `$ ./gulp --series clean watch`
- 3. `$ go build --tags debug` (from `apps/nsqadmin` directory)
+ 3. `$ cd .. && make && ./build/nsqadmin --dev-static-dir=nsqadmin/static/build --lookupd-http-address=<...>`
  4. make changes to static assets (repeat step 3 only if you make changes to any Go code)
 
 ### Build
 
  1. `$ ./gulp --series clean build`
+ 2. `$ go-bindata --pkg=nsqadmin --prefix=static/build/ static/build/...` (for "legacy" go < 1.16)

nsqadmin/http.go

@@ -48,11 +48,12 @@ func NewSingleHostReverseProxy(target *url.URL, connectTimeout time.Duration, re
 }
 
 type httpServer struct {
-	nsqadmin *NSQAdmin
-	router   http.Handler
-	client   *http_api.Client
-	ci       *clusterinfo.ClusterInfo
-	basePath string
+	nsqadmin     *NSQAdmin
+	router       http.Handler
+	client       *http_api.Client
+	ci           *clusterinfo.ClusterInfo
+	basePath     string
+	devStaticDir string
 }
 
 func NewHTTPServer(nsqadmin *NSQAdmin) *httpServer {
@@ -66,12 +67,15 @@ func NewHTTPServer(nsqadmin *NSQAdmin) *httpServer {
 	router.PanicHandler = http_api.LogPanicHandler(nsqadmin.logf)
 	router.NotFound = http_api.LogNotFoundHandler(nsqadmin.logf)
 	router.MethodNotAllowed = http_api.LogMethodNotAllowedHandler(nsqadmin.logf)
+
 	s := &httpServer{
 		nsqadmin: nsqadmin,
 		router:   router,
 		client:   client,
 		ci:       clusterinfo.New(nsqadmin.logf, client),
-		basePath: nsqadmin.getOpts().BasePath,
+
+		basePath:     nsqadmin.getOpts().BasePath,
+		devStaticDir: nsqadmin.getOpts().DevStaticDir,
 	}
 
 	bp := func(p string) string {
@@ -164,7 +168,17 @@ func (s *httpServer) indexHandler(w http.ResponseWriter, req *http.Request, ps h
 func (s *httpServer) staticAssetHandler(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {
 	assetName := ps.ByName("asset")
 
-	asset, err := staticAsset(assetName)
+	var (
+		asset []byte
+		err   error
+	)
+	if s.devStaticDir != "" {
+		s.nsqadmin.logf(LOG_DEBUG, "using dev dir %q for static asset %q", s.devStaticDir, assetName)
+		fsPath := path.Join(s.devStaticDir, assetName)
+		asset, err = ioutil.ReadFile(fsPath)
+	} else {
+		asset, err = staticAsset(assetName)
+	}
 	if err != nil {
 		return nil, http_api.Err{404, "NOT_FOUND"}
 	}

nsqadmin/options.go

@@ -14,6 +14,8 @@ type Options struct {
 	HTTPAddress string `flag:"http-address"`
 	BasePath    string `flag:"base-path"`
 
+	DevStaticDir string `flag:"dev-static-dir"`
+
 	GraphiteURL   string `flag:"graphite-url"`
 	ProxyGraphite bool   `flag:"proxy-graphite"`
 

nsqadmin/static.go

@@ -1,5 +1,5 @@
-//go:build go1.16 && !debug
-// +build go1.16,!debug
+//go:build go1.16
+// +build go1.16
 
 package nsqadmin