envelope all json responses in api endpoints

api/api.go

@@ -1,6 +1,7 @@
 package api
 
 import (
+	"encoding/json"
 	"log"
 	"net/http"
 	"strconv"
@@ -11,6 +12,17 @@ import (
 const defaultPeriod = 7
 const defaultLimit = 10
 
+type envelope struct {
+	Data  interface{}
+	Error interface{}
+}
+
+func respond(w http.ResponseWriter, d interface{}) {
+	w.Header().Set("Content-Type", "application/json")
+	enc := json.NewEncoder(w)
+	enc.Encode(d)
+}
+
 // log fatal errors
 func checkError(err error) {
 	if err != nil {

api/auth.go

@@ -20,17 +20,19 @@ var store = sessions.NewFilesystemStore("./storage/sessions/", []byte(os.Getenv(
 
 // URL: POST /api/session
 var LoginHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-	var l login
-	json.NewDecoder(r.Body).Decode(&l)
 
 	// check login creds
+	var l login
+	json.NewDecoder(r.Body).Decode(&l)
 	var hashedPassword string
 	var u models.User
 	stmt, _ := db.Conn.Prepare("SELECT id, email, password FROM users WHERE email = ? LIMIT 1")
 	err := stmt.QueryRow(l.Email).Scan(&u.ID, &u.Email, &hashedPassword)
 
+	// compare pwd
 	if err != nil || bcrypt.CompareHashAndPassword([]byte(hashedPassword), []byte(l.Password)) != nil {
 		w.WriteHeader(http.StatusUnauthorized)
+		respond(w, envelope{Error: "invalid_credentials"})
 		return
 	}
 
@@ -40,8 +42,7 @@ var LoginHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request)
 	err = session.Save(r, w)
 	checkError(err)
 
-	w.Header().Set("Content-Type", "application/json")
-	w.Write([]byte("true"))
+	respond(w, envelope{Data: true})
 })
 
 // URL: DELETE /api/session
@@ -52,8 +53,7 @@ var LogoutHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request
 		session.Save(r, w)
 	}
 
-	w.Header().Set("Content-Type", "application/json")
-	w.Write([]byte("true"))
+	respond(w, envelope{Data: true})
 })
 
 /* middleware */

api/browsers.go

@@ -1,17 +1,13 @@
 package api
 
 import (
-	"encoding/json"
-	"net/http"
-
 	"github.com/dannyvankooten/ana/count"
+	"net/http"
 )
 
 // URL: /api/browsers
 var GetBrowsersHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	before, after := getRequestedPeriods(r)
 	results := count.Browsers(before, after, getRequestedLimit(r))
-
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(results)
+	respond(w, envelope{Data: results})
 })

api/languages.go

@@ -1,7 +1,6 @@
 package api
 
 import (
-	"encoding/json"
 	"net/http"
 
 	"github.com/dannyvankooten/ana/count"
@@ -11,6 +10,5 @@ import (
 var GetLanguagesHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	before, after := getRequestedPeriods(r)
 	results := count.Languages(before, after, getRequestedLimit(r))
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(results)
+	respond(w, envelope{Data: results})
 })

api/pageviews.go

@@ -1,7 +1,6 @@
 package api
 
 import (
-	"encoding/json"
 	"net/http"
 
 	"github.com/dannyvankooten/ana/count"
@@ -44,22 +43,19 @@ var GetPageviewsHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.R
 	err = rows.Err()
 	checkError(err)
 
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(results)
+	respond(w, envelope{Data: results})
 })
 
 // URL: /api/pageviews/count
 var GetPageviewsCountHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	before, after := getRequestedPeriods(r)
 	result := count.Pageviews(before, after)
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(result)
+	respond(w, envelope{Data: result})
 })
 
 // URL: /api/pageviews/group/day
 var GetPageviewsPeriodCountHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	before, after := getRequestedPeriods(r)
 	results := count.PageviewsPerDay(before, after)
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(results)
+	respond(w, envelope{Data: results})
 })

api/referrers.go

@@ -1,7 +1,6 @@
 package api
 
 import (
-	"encoding/json"
 	"net/http"
 
 	"github.com/dannyvankooten/ana/count"
@@ -11,6 +10,5 @@ import (
 var GetReferrersHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	before, after := getRequestedPeriods(r)
 	results := count.Referrers(before, after, getRequestedLimit(r))
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(results)
+	respond(w, envelope{Data: results})
 })

api/screens.go

@@ -1,7 +1,6 @@
 package api
 
 import (
-	"encoding/json"
 	"net/http"
 
 	"github.com/dannyvankooten/ana/count"
@@ -11,6 +10,5 @@ import (
 var GetScreenResolutionsHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	before, after := getRequestedPeriods(r)
 	results := count.Screens(before, after, getRequestedLimit(r))
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(results)
+	respond(w, envelope{Data: results})
 })

api/visitors.go

@@ -1,7 +1,6 @@
 package api
 
 import (
-	"encoding/json"
 	"net/http"
 
 	"github.com/dannyvankooten/ana/count"
@@ -11,21 +10,18 @@ import (
 var GetVisitorsCountHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	before, after := getRequestedPeriods(r)
 	result := count.Visitors(before, after)
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(result)
+	respond(w, envelope{Data: result})
 })
 
 // URL: /api/visitors/count/realtime
 var GetVisitorsRealtimeCountHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	result := count.RealtimeVisitors()
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(result)
+	respond(w, envelope{Data: result})
 })
 
 // URL: /api/visitors/count/group/:period
 var GetVisitorsPeriodCountHandler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	before, after := getRequestedPeriods(r)
 	results := count.VisitorsPerDay(before, after)
-	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(results)
+	respond(w, envelope{Data: results})
 })