Add back consoles link.

Goes in index.html in consoles or else user data, if present.

Change-Id: I5303d30aa24ca0c20d2e0f49121e04a260b9c4f4

web/templates/_base.html

@@ -17,6 +17,10 @@
         <div class="container-fluid">
           <a class="brand" href="/">Prometheus</a>
           <ul class="nav">
+            {{$consoles := getConsoles}}
+            {{if $consoles}}
+            <li><a href="{{$consoles}}">Consoles</a></li>
+            {{ end }}
             <li><a href="/alerts">Alerts</a></li>
             <li><a href="/graph">Graph</a></li>
             <li><a href="/">Status</a></li>

web/web.go

@@ -128,10 +128,23 @@ func getTemplateFile(name string) (string, error) {
 	}
 }
 
+func getConsoles() string {
+	if _, err := os.Stat(*consoleTemplatesPath + "/index.html"); !os.IsNotExist(err) {
+		return "/consoles/index.html"
+	}
+	if *userAssetsPath != "" {
+		if _, err := os.Stat(*userAssetsPath + "/index.html"); !os.IsNotExist(err) {
+			return "/user/index.html"
+		}
+	}
+	return ""
+}
+
 func getTemplate(name string) (t *template.Template, err error) {
 	t = template.New("_base")
 	t.Funcs(template.FuncMap{
-		"since": time.Since,
+		"since":       time.Since,
+		"getConsoles": getConsoles,
 	})
 	file, err := getTemplateFile("_base")
 	if err != nil {