agent: static UI is configurable

command/agent/command.go

@@ -71,6 +71,7 @@ func (c *Command) readConfig() *Config {
 	cmdFlags.StringVar(&cmdConfig.NodeName, "node", "", "node name")
 	cmdFlags.StringVar(&cmdConfig.Datacenter, "dc", "", "node datacenter")
 	cmdFlags.StringVar(&cmdConfig.DataDir, "data-dir", "", "path to the data directory")
+	cmdFlags.BoolVar(&cmdConfig.EnableUi, "ui", false, "enable the built-in web UI")
 	cmdFlags.StringVar(&cmdConfig.UiDir, "ui-dir", "", "path to the web UI directory")
 	cmdFlags.StringVar(&cmdConfig.PidFile, "pid-file", "", "path to file to store PID")
 	cmdFlags.StringVar(&cmdConfig.EncryptKey, "encrypt", "", "gossip encryption key")
@@ -990,6 +991,7 @@ Options:
   -rejoin                  Ignores a previous leave and attempts to rejoin the cluster.
   -server                  Switches agent to server mode.
   -syslog                  Enables logging to syslog
+  -ui                      Enables the built-in static web UI server
   -ui-dir=path             Path to directory containing the Web UI resources
   -pid-file=path           Path to file to store agent PID
 

command/agent/config.go

@@ -270,6 +270,10 @@ type Config struct {
 	RetryIntervalWan    time.Duration `mapstructure:"-" json:"-"`
 	RetryIntervalWanRaw string        `mapstructure:"retry_interval_wan"`
 
+	// EnableUi enables the statically-compiled assets for the Consul web UI and
+	// serves them at the default /ui/ endpoint automatically.
+	EnableUi bool `mapstructure:"ui"`
+
 	// UiDir is the directory containing the Web UI resources.
 	// If provided, the UI endpoints will be enabled.
 	UiDir string `mapstructure:"ui_dir"`
@@ -1004,6 +1008,9 @@ func MergeConfig(a, b *Config) *Config {
 	if b.Addresses.RPC != "" {
 		result.Addresses.RPC = b.Addresses.RPC
 	}
+	if b.EnableUi {
+		result.EnableUi = true
+	}
 	if b.UiDir != "" {
 		result.UiDir = b.UiDir
 	}

command/agent/config_test.go

@@ -441,6 +441,17 @@ func TestDecodeConfig(t *testing.T) {
 		t.Fatalf("bad: %#v", config)
 	}
 
+	// Static UI server
+	input = `{"ui": true}`
+	config, err = DecodeConfig(bytes.NewReader([]byte(input)))
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if !config.EnableUi {
+		t.Fatalf("bad: %#v", config)
+	}
+
 	// UI Dir
 	input = `{"ui_dir": "/opt/consul-ui"}`
 	config, err = DecodeConfig(bytes.NewReader([]byte(input)))
@@ -1230,6 +1241,7 @@ func TestMergeConfig(t *testing.T) {
 		Services:               []*ServiceDefinition{nil},
 		StartJoin:              []string{"1.1.1.1"},
 		StartJoinWan:           []string{"1.1.1.1"},
+		EnableUi:               true,
 		UiDir:                  "/opt/consul-ui",
 		EnableSyslog:           true,
 		RejoinAfterLeave:       true,

command/agent/http.go

@@ -278,7 +278,7 @@ func (s *HTTPServer) registerHandlers(enableDebug bool) {
 	// Use the custom UI dir if provided.
 	if s.uiDir != "" {
 		s.mux.Handle("/ui/", http.StripPrefix("/ui/", http.FileServer(http.Dir(s.uiDir))))
-	} else {
+	} else if s.agent.config.EnableUi {
 		s.mux.Handle("/ui/", http.StripPrefix("/ui/", http.FileServer(assetFS())))
 	}
 

command/agent/http_test.go

@@ -630,6 +630,26 @@ func TestScadaHTTP(t *testing.T) {
 	scadaHttp.mux.HandleFunc("/debug/pprof/symbol", mockFn)
 }
 
+func TestEnableWebUI(t *testing.T) {
+	httpTestWithConfig(t, func(s *HTTPServer) {
+		req, err := http.NewRequest("GET", "/ui/", nil)
+		if err != nil {
+			t.Fatalf("err: %v", err)
+		}
+
+		// Perform the request
+		resp := httptest.NewRecorder()
+		s.mux.ServeHTTP(resp, req)
+
+		// Check the result
+		if resp.Code != 200 {
+			t.Fatalf("should handle ui")
+		}
+	}, func(c *Config) {
+		c.EnableUi = true
+	})
+}
+
 // assertIndex tests that X-Consul-Index is set and non-zero
 func assertIndex(t *testing.T, resp *httptest.ResponseRecorder) {
 	header := resp.Header().Get("X-Consul-Index")