Change html templating style

main.go

@@ -32,24 +32,38 @@ const appVersion = "1.0.1"
 
 var src = rand.NewSource(time.Now().UnixNano())
 var pool = cache.New(240*time.Hour, 1*time.Hour)
-var okTmpl = template.Must(template.ParseFiles("templates/ok.html"))
-var indexTmpl = template.Must(template.ParseFiles("templates/index.html"))
-var returnTmpl = template.Must(template.ParseFiles("templates/returnPage.html"))
-var notFoundTmpl = template.Must(template.ParseFiles("templates/404.html"))
-var badRequestTmpl = template.Must(template.ParseFiles("templates/400.html"))
-var internalErrorTmpl = template.Must(template.ParseFiles("templates/500.html"))
+var templates *template.Template
+var allFiles []string
+
+func init() {
+	files, err := ioutil.ReadDir("templates")
+	if err != nil {
+		log.Fatalln(err)
+	}
+	for _, file := range files {
+		filename := file.Name()
+		if strings.HasSuffix(filename, ".html") {
+			allFiles = append(allFiles, "templates/"+filename)
+		}
+	}
+	templates, err = template.ParseFiles(allFiles...)
+	if err != nil {
+		log.Fatalln(err)
+	}
+}
 
 func index(w http.ResponseWriter, r *http.Request) {
-	indexTmpl.Execute(w, indexTmpl)
+	t := templates.Lookup("index.html")
+	t.Execute(w, nil)
 }
 
 // get executes the  GET command
 func get(key string) (string, bool) {
 	value, status := pool.Get(key)
-	if status {
-		return value.(string), status
+	if !status {
+		return "", status
 	}
-	return "", false
+	return value.(string), status
 }
 
 // set executes the redis SET command
@@ -63,6 +77,7 @@ func set(key, suffix string) {
 func redirect(w http.ResponseWriter, r *http.Request, path string) {
 	vals := mux.Vars(r)
 	key := vals["key"]
+	t := templates.Lookup("404.html")
 	if path != "" {
 		key = strings.Replace(key, path, "", 1)
 	}
@@ -71,7 +86,7 @@ func redirect(w http.ResponseWriter, r *http.Request, path string) {
 	key, status := get(key)
 	if !status {
 		w.WriteHeader(http.StatusNotFound)
-		notFoundTmpl.Execute(w, nil)
+		t.Execute(w, nil)
 		return
 	}
 	u, _ := url.Parse(key)
@@ -79,10 +94,6 @@ func redirect(w http.ResponseWriter, r *http.Request, path string) {
 		u.Scheme = "https"
 	}
 	http.Redirect(w, r, u.String(), http.StatusFound)
-	} else {
-		w.WriteHeader(http.StatusNotFound)
-		notFoundTmpl.Execute(w, notFoundTmpl)
-	}
 }
 
 // shortner reads url from a POST request, validates the url, generate a
@@ -91,9 +102,11 @@ func redirect(w http.ResponseWriter, r *http.Request, path string) {
 // then if writes the kv pair suffix, url to the database and return the
 // shortened url to the user
 func shortner(w http.ResponseWriter, r *http.Request, proto, domain, hostSuf, path string, urlSize int) {
+	ret := templates.Lookup("returnPage.html")
+	badR := templates.Lookup("400.html")
 	if !govalidator.IsURL(r.FormValue("url")) {
 		w.WriteHeader(http.StatusBadRequest)
-		badRequestTmpl.Execute(w, nil)
+		badR.Execute(w, nil)
 		return
 	}
 	u, _ := url.Parse(r.FormValue("url"))
@@ -108,7 +121,7 @@ func shortner(w http.ResponseWriter, r *http.Request, proto, domain, hostSuf, pa
 	}
 	set(u.String(), suffix)
 	shortend := proto + "://" + domain + hostSuf + path + suffix
-		returnTmpl.Execute(w, shortend)
+	ret.Execute(w, shortend)
 }
 
 // randStringBytesMaskImprSrc Generate random string of n size
@@ -132,9 +145,10 @@ func randStringBytesMaskImprSrc(n int) string {
 // internalError receives a http.ResponseWriter, msg and error and
 // return a internal error page with http code 500 to the user
 func internalError(w http.ResponseWriter, msg string, err error) {
+	t := templates.Lookup("500.html")
 	log.Println(err)
 	w.WriteHeader(http.StatusInternalServerError)
-	internalErrorTmpl.Execute(w, msg+err.Error())
+	t.Execute(w, msg+err.Error())
 }
 
 // itemsCount returns the number of kv pairs on the in meomry database
@@ -163,6 +177,7 @@ func itemsDump(w http.ResponseWriter, r *http.Request) {
 
 // itemsFromFile loads kv pairs from the dumpFile json to the in memory database
 func itemsFromFile(w http.ResponseWriter, r *http.Request, dumpFile string) {
+	t := templates.Lookup("ok.html")
 	jsonFile, err := ioutil.ReadFile(dumpFile)
 	var dumpObj map[string]cache.Item
 	json.Unmarshal([]byte(jsonFile), &dumpObj)
@@ -170,12 +185,13 @@ func itemsFromFile(w http.ResponseWriter, r *http.Request, dumpFile string) {
 		internalError(w, "Cannot open file "+dumpFile+": ", err)
 	} else {
 		pool = cache.NewFrom(240*time.Hour, 1*time.Hour, dumpObj)
-		okTmpl.Execute(w, "Imported "+strconv.Itoa(len(dumpObj))+" items to the DB")
+		t.Execute(w, "Imported "+strconv.Itoa(len(dumpObj))+" items to the DB")
 	}
 }
 
 // itemsFromPost loads kv pairs from a json POST to the in memory database
 func itemsFromPost(w http.ResponseWriter, r *http.Request) {
+	t := templates.Lookup("ok.html")
 	decoder := json.NewDecoder(r.Body)
 	var dumpObj map[string]cache.Item
 	err := decoder.Decode(&dumpObj)
@@ -183,12 +199,13 @@ func itemsFromPost(w http.ResponseWriter, r *http.Request) {
 		internalError(w, "Cannot parse JSON: ", err)
 	} else {
 		pool = cache.NewFrom(240*time.Hour, 1*time.Hour, dumpObj)
-		okTmpl.Execute(w, "Imported "+strconv.Itoa(len(dumpObj))+" items to the DB")
+		t.Execute(w, "Imported "+strconv.Itoa(len(dumpObj))+" items to the DB")
 	}
 }
 
 // itemsDumpToFile dumps the kv pairs from the in memory database to the dumpFile
 func itemsDumpToFile(w http.ResponseWriter, r *http.Request, dumpFile string) {
+	t := templates.Lookup("ok.html")
 	dumpObj, _ := json.Marshal(
 		pool.Items(),
 	)
@@ -196,7 +213,7 @@ func itemsDumpToFile(w http.ResponseWriter, r *http.Request, dumpFile string) {
 	if err != nil {
 		internalError(w, "Failed to open json file: ", err)
 	} else {
-		okTmpl.Execute(w, "Dump writen to: "+dumpFile)
+		t.Execute(w, "Dump writen to: "+dumpFile)
 	}
 }
 
@@ -220,7 +237,7 @@ func main() {
 	}
 
 	if *port > 65535 || *port < 1 {
-
+		log.Fatalln("Invalid port number")
 	}
 	if *path != "" && !strings.HasSuffix(*path, "/") {
 		*path = *path + "/"