Fix CORS, fix tracking script & show Hello response when unknown URL requested

go.mod

@@ -6,6 +6,7 @@ require (
 	github.com/gobuffalo/packr/v2 v2.0.9
 	github.com/golang-migrate/migrate/v4 v4.2.5
 	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 // indirect
+	github.com/gorilla/handlers v1.4.0
 	github.com/gorilla/mux v1.7.0
 	github.com/mattn/go-sqlite3 v1.10.0
 	github.com/wcharczuk/go-chart v2.0.1+incompatible

go.sum

@@ -77,6 +77,8 @@ github.com/googleapis/gax-go v2.0.0+incompatible/go.mod h1:SFVmujtThgffbyetf+mdk
 github.com/gopherjs/gopherjs v0.0.0-20181004151105-1babbf986f6f/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/gorilla/context v1.1.1 h1:AWwleXJkX/nhcU9bZSnZoi3h/qGYqQAGhq6zZe/aQW8=
 github.com/gorilla/context v1.1.1/go.mod h1:kBGZzfjB9CEq2AlWe17Uuf7NDRt0dE0s8S51q0aT7Yg=
+github.com/gorilla/handlers v1.4.0 h1:XulKRWSQK5uChr4pEgSE4Tc/OcmnU9GJuSwdog/tZsA=
+github.com/gorilla/handlers v1.4.0/go.mod h1:Qkdc/uu4tH4g6mTK6auzZ766c4CA0Ng8+o/OAirnOIQ=
 github.com/gorilla/mux v1.6.2 h1:Pgr17XVTNXAk3q/r4CpKzC5xBM/qW1uVLV+IhRZpIIk=
 github.com/gorilla/mux v1.6.2/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
 github.com/gorilla/mux v1.7.0 h1:tOSd0UKHQd6urX6ApfOn4XdBMY6Sh1MfxV3kmaazO+U=

main.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"github.com/gobuffalo/packr/v2"
+	"github.com/gorilla/handlers"
 	"github.com/gorilla/mux"
 	"github.com/wcharczuk/go-chart"
 	"github.com/wcharczuk/go-chart/drawing"
@@ -15,9 +16,10 @@ import (
 )
 
 type kis3 struct {
-	db     *Database
-	router *mux.Router
-	fs     http.Handler
+	db        *Database
+	router    *mux.Router
+	staticBox *packr.Box
+	staticFS  http.Handler
 }
 
 var (
@@ -43,9 +45,18 @@ func (kis3 *kis3) setupDB() (e error) {
 
 func (kis3 *kis3) setupRouter() {
 	kis3.router = mux.NewRouter()
-	kis3.router.HandleFunc("/view", kis3.trackView)
+
+	corsHandler := handlers.CORS(handlers.AllowedOrigins([]string{"*"}))
+
+	viewRouter := kis3.router.PathPrefix("/view").Subrouter()
+	viewRouter.Use(corsHandler)
+	viewRouter.Path("").HandlerFunc(kis3.trackView)
+
 	kis3.router.HandleFunc("/stats", kis3.requestStats)
-	kis3.router.PathPrefix("/").Handler(http.HandlerFunc(kis3.serveStaticFile))
+
+	staticRouter := kis3.router.PathPrefix("").Subrouter()
+	staticRouter.Use(corsHandler)
+	staticRouter.PathPrefix("").Handler(http.HandlerFunc(kis3.serveStaticFile))
 }
 
 func (kis3 kis3) startListening() {
@@ -56,7 +67,7 @@ func (kis3 kis3) startListening() {
 }
 
 func (kis3 kis3) trackView(w http.ResponseWriter, r *http.Request) {
-	url := r.URL.Query().Get("url")
+	url := r.Header.Get("Referer") // URL of requesting source
 	ref := r.URL.Query().Get("ref")
 	if r.Header.Get("DNT") == "1" && appConfig.dnt {
 		fmt.Println("Not tracking because of DNT")
@@ -67,15 +78,21 @@ func (kis3 kis3) trackView(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
+func sendHelloResponse(w http.ResponseWriter) {
+	_, _ = fmt.Fprint(w, "Hello from KISSS")
+}
+
 func (kis3 kis3) serveStaticFile(w http.ResponseWriter, r *http.Request) {
-	if kis3.fs == nil {
-		kis3.fs = http.FileServer(packr.New("staticFiles", "./static"))
+	if kis3.staticBox == nil || kis3.staticFS == nil {
+		kis3.staticBox = packr.New("staticFiles", "./static")
+		kis3.staticFS = http.FileServer(kis3.staticBox)
 	}
-	// Fix, because file server isn't serving index.html otherwise
-	if r.URL.Path == "/" || r.URL.Path == "/index.html" {
-		r.URL.Path = "/default.html"
+	uPath := r.URL.Path
+	if uPath != "/" && kis3.staticBox.Has(uPath) {
+		kis3.staticFS.ServeHTTP(w, r)
+	} else {
+		sendHelloResponse(w)
 	}
-	kis3.fs.ServeHTTP(w, r)
 }
 
 func (kis3 kis3) requestStats(w http.ResponseWriter, r *http.Request) {

static/kis3.js

@@ -1,9 +1,8 @@
 (function () {
     var request = new XMLHttpRequest();
-    var url = document.currentScript.baseURI
-        + "view?url=" + window.decodeURI(document.documentURI);
+    var url = document.currentScript.src.replace("kis3.js", "view?");
     if (document.referrer && document.referrer.length > 0) {
-        url += window.decodeURI(document.referrer);
+        url += "ref=" + window.decodeURI(document.referrer);
     }
     request.onload = function () {
         if (request.status >= 200 && request.status < 300) {

static/test.html

@@ -6,6 +6,6 @@
 </head>
 <body>
 Welcome to <b>KISSS</b>
-<script src="kis3.js"></script>
+<script src="http://localhost:8080/kis3.js"></script>
 </body>
 </html>