recipe: twitter like api

Signed-off-by: Vishal Rana <vr@labstack.com>

glide.lock

@@ -1,5 +1,5 @@
-hash: c3a41d26c94d8101a2aeaea5bc438cb75c5e9b7bd80850c7ec806c00c535d1c7
-updated: 2016-12-02T08:49:24.85691-08:00
+hash: 19ec155dd3ba25b967dd609c52b748b5302a30bede03936645c12fef7e9edd75
+updated: 2016-12-05T20:47:56.995548765-08:00
 imports:
 - name: github.com/daaku/go.zipexe
   version: a5fe2436ffcb3236e175e5149162b41cd28bd27d
@@ -57,6 +57,13 @@ imports:
   - internal/log
   - internal/modules
   - internal/remote_api
+- name: gopkg.in/mgo.v2
+  version: 3f83fa5005286a7fe593b055f0d7771a7dce4655
+  subpackages:
+  - bson
+  - internal/json
+  - internal/sasl
+  - internal/scram
 testImports:
 - name: github.com/davecgh/go-spew
   version: 04cdfd42973bb9c8589fd6a731800cf222fde1a9

glide.yaml

@@ -19,6 +19,7 @@ import:
   subpackages:
   - websocket
 - package: google.golang.org/appengine
+- package: gopkg.in/mgo.v2
 testImport:
 - package: github.com/stretchr/testify
   subpackages:

recipe/twitter/handler/handler.go

@@ -0,0 +1,14 @@
+package handler
+
+import mgo "gopkg.in/mgo.v2"
+
+type (
+	Handler struct {
+		DB *mgo.Session
+	}
+)
+
+const (
+	// Key (Should come from somewhere else).
+	Key = "secret"
+)

recipe/twitter/handler/post.go

@@ -0,0 +1,73 @@
+package handler
+
+import (
+	"net/http"
+	"strconv"
+
+	"github.com/labstack/echo"
+	"github.com/labstack/echo/recipe/twitter/model"
+	mgo "gopkg.in/mgo.v2"
+	"gopkg.in/mgo.v2/bson"
+)
+
+func (h *Handler) CreatePost(c echo.Context) (err error) {
+	u := &model.User{
+		ID: bson.ObjectIdHex(userIDFromToken(c)),
+	}
+	p := &model.Post{
+		ID:   bson.NewObjectId(),
+		From: u.ID.Hex(),
+	}
+	if err = c.Bind(p); err != nil {
+		return
+	}
+
+	// Validation
+	if p.To == "" || p.Message == "" {
+		return &echo.HTTPError{Code: http.StatusBadRequest, Message: "invalid to or message fields"}
+	}
+
+	// Find user from database
+	db := h.DB.Clone()
+	defer db.Close()
+	if err = db.DB("twitter").C("users").FindId(u.ID).One(u); err != nil {
+		if err == mgo.ErrNotFound {
+			return echo.ErrNotFound
+		}
+		return
+	}
+
+	// Save post in database
+	if err = db.DB("twitter").C("posts").Insert(p); err != nil {
+		return
+	}
+	return c.JSON(http.StatusCreated, p)
+}
+
+func (h *Handler) FetchPost(c echo.Context) (err error) {
+	userID := userIDFromToken(c)
+	page, _ := strconv.Atoi(c.QueryParam("page"))
+	limit, _ := strconv.Atoi(c.QueryParam("limit"))
+
+	// Defaults
+	if page == 0 {
+		page = 1
+	}
+	if limit == 0 {
+		limit = 100
+	}
+
+	// Retrieve posts from database
+	posts := []*model.Post{}
+	db := h.DB.Clone()
+	if err = db.DB("twitter").C("posts").
+		Find(bson.M{"to": userID}).
+		Skip((page - 1) * limit).
+		Limit(limit).
+		All(&posts); err != nil {
+		return
+	}
+	defer db.Close()
+
+	return c.JSON(http.StatusOK, posts)
+}

recipe/twitter/handler/user.go

@@ -0,0 +1,97 @@
+package handler
+
+import (
+	"net/http"
+	"time"
+
+	jwt "github.com/dgrijalva/jwt-go"
+	"github.com/labstack/echo"
+	"github.com/labstack/echo/recipe/twitter/model"
+	mgo "gopkg.in/mgo.v2"
+	"gopkg.in/mgo.v2/bson"
+)
+
+func (h *Handler) Signup(c echo.Context) (err error) {
+	// Bind
+	u := &model.User{ID: bson.NewObjectId()}
+	if err = c.Bind(u); err != nil {
+		return
+	}
+
+	// Validate
+	if u.Email == "" || u.Password == "" {
+		return &echo.HTTPError{Code: http.StatusBadRequest, Message: "invalid email or password"}
+	}
+
+	// Save user
+	db := h.DB.Clone()
+	defer db.Close()
+	if err = db.DB("twitter").C("users").Insert(u); err != nil {
+		return
+	}
+
+	return c.JSON(http.StatusCreated, u)
+}
+
+func (h *Handler) Login(c echo.Context) (err error) {
+	// Bind
+	u := new(model.User)
+	if err = c.Bind(u); err != nil {
+		return
+	}
+
+	// Find user
+	db := h.DB.Clone()
+	defer db.Close()
+	if err = db.DB("twitter").C("users").
+		Find(bson.M{"email": u.Email, "password": u.Password}).One(u); err != nil {
+		if err == mgo.ErrNotFound {
+			return &echo.HTTPError{Code: http.StatusUnauthorized, Message: "invalid email or password"}
+		}
+		return
+	}
+
+	//-----
+	// JWT
+	//-----
+
+	// Create token
+	token := jwt.New(jwt.SigningMethodHS256)
+
+	// Set claims
+	claims := token.Claims.(jwt.MapClaims)
+	claims["id"] = u.ID
+	claims["exp"] = time.Now().Add(time.Hour * 72).Unix()
+
+	// Generate encoded token and send it as response
+	u.Token, err = token.SignedString([]byte(Key))
+	if err != nil {
+		return err
+	}
+
+	u.Password = "" // Don't send password
+	return c.JSON(http.StatusOK, u)
+}
+
+func (h *Handler) Follow(c echo.Context) (err error) {
+	userID := userIDFromToken(c)
+	id := c.Param("id")
+
+	// Add a follower to user
+	db := h.DB.Clone()
+	defer db.Close()
+	if err = db.DB("twitter").C("users").
+		UpdateId(bson.ObjectIdHex(id), bson.M{"$addToSet": bson.M{"followers": userID}}); err != nil {
+		if err == mgo.ErrNotFound {
+			return echo.ErrNotFound
+		}
+	}
+
+	return
+}
+
+func userIDFromToken(c echo.Context) string {
+	user := c.Get("user").(*jwt.Token)
+	claims := user.Claims.(jwt.MapClaims)
+	return claims["id"].(string)
+}

recipe/twitter/model/post.go

@@ -0,0 +1,12 @@
+package model
+
+import "gopkg.in/mgo.v2/bson"
+
+type (
+	Post struct {
+		ID      bson.ObjectId `json:"id" bson:"_id,omitempty"`
+		To      string        `json:"to" bson:"to"`
+		From    string        `json:"from" bson:"from"`
+		Message string        `json:"message" bson:"message"`
+	}
+)

recipe/twitter/model/user.go

@@ -0,0 +1,13 @@
+package model
+
+import "gopkg.in/mgo.v2/bson"
+
+type (
+	User struct {
+		ID        bson.ObjectId `json:"id" bson:"_id,omitempty"`
+		Email     string        `json:"email" bson:"email"`
+		Password  string        `json:"password,omitempty" bson:"password"`
+		Token     string        `json:"token,omitempty" bson:"-"`
+		Followers []string      `json:"followers,omitempty" bson:"followers,omitempty"`
+	}
+)

recipe/twitter/server.go

@@ -0,0 +1,52 @@
+package main
+
+import (
+	"github.com/labstack/echo"
+	"github.com/labstack/echo/middleware"
+	"github.com/labstack/echo/recipe/twitter/handler"
+	"github.com/labstack/gommon/log"
+	mgo "gopkg.in/mgo.v2"
+)
+
+func main() {
+	e := echo.New()
+	e.Logger.SetLevel(log.ERROR)
+	e.Use(middleware.Logger())
+	e.Use(middleware.JWTWithConfig(middleware.JWTConfig{
+		SigningKey: []byte(handler.Key),
+		Skipper: func(c echo.Context) bool {
+			// Skip authentication for and signup login requests
+			if c.Path() == "/login" || c.Path() == "/signup" {
+				return true
+			}
+			return false
+		},
+	}))
+
+	// Database connection
+	db, err := mgo.Dial("localhost")
+	if err != nil {
+		e.Logger.Fatal(err)
+	}
+
+	// Create indices
+	if err = db.Copy().DB("twitter").C("users").EnsureIndex(mgo.Index{
+		Key:    []string{"email"},
+		Unique: true,
+	}); err != nil {
+		log.Fatal(err)
+	}
+
+	// Initialize handler
+	h := &handler.Handler{DB: db}
+
+	// Routes
+	e.POST("/signup", h.Signup)
+	e.POST("/login", h.Login)
+	e.POST("/follow/:id", h.Follow)
+	e.POST("/posts", h.CreatePost)
+	e.GET("/feed", h.FetchPost)
+
+	// Start server
+	e.Logger.Fatal(e.Start(":1323"))
+}

website/content/recipes/twitter.md

@@ -0,0 +1,202 @@
++++
+title = "Twitter API Example"
+description = "Twitter API example for Echo"
+[menu.main]
+  name = "Twitter"
+  parent = "recipes"
+  weight = 2 
++++
+
+This recipe shows how to create a Twitter like REST API using MongoDB (Database),
+JWT (API security) and JSON (Data exchange).
+
+## Models
+
+`user.go`
+
+{{< embed "twitter/model/user.go" >}}
+
+`post.go`
+
+{{< embed "twitter/model/post.go" >}}
+
+## Handlers
+
+`handler.go`
+
+{{< embed "twitter/handler/handler.go" >}}
+
+`user.go`
+
+{{< embed "twitter/handler/user.go" >}}
+
+`post.go`
+
+{{< embed "twitter/handler/post.go" >}}
+
+## API
+
+### Signup
+
+User signup
+
+- Retrieve user credentials from the body and validate against database.
+- For invalid email or password, send `400 - Bad Request` response.
+- For valid email and password, save user in database and send `201 - Created` response.
+  - 
+
+#### Request
+
+```sh
+curl \
+  -X POST \
+  http://localhost:1323/signup \
+  -H "Content-Type: application/json" \
+  -d '{"email":"jon@labstack.com","password":"shhh!"}'
+```
+
+#### Response
+
+`201 - Created`
+
+```js
+{
+  "id": "58465b4ea6fe886d3215c6df",
+  "email": "jon@labstack.com",
+  "password": "shhh!"
+}
+```
+
+### Login
+
+User login
+
+- Retrieve user credentials from the body and validate against database.
+- For invalid credentials, send `401 - Unauthorized` response.
+- For valid credentials, send `200 - OK` response:
+  - Generate JWT for the user and send it as response.
+  - Each subsequent request must include JWT in the `Authorization` header.
+
+Method: `POST`<br>
+Path: `/login`
+
+#### Request
+
+```sh
+curl \
+  -X POST \
+  http://localhost:1323/login \
+  -H "Content-Type: application/json" \
+  -d '{"email":"jon@labstack.com","password":"shhh!"}'
+```
+
+#### Response
+
+`200 - OK`
+
+```js
+{
+  "id": "58465b4ea6fe886d3215c6df",
+  "email": "jon@labstack.com",
+  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJleHAiOjE0ODEyNjUxMjgsImlkIjoiNTg0NjViNGVhNmZlODg2ZDMyMTVjNmRmIn0.1IsGGxko1qMCsKkJDQ1NfmrZ945XVC9uZpcvDnKwpL0"
+}
+```
+
+Client should store the token, for browsers, you may use local storage.
+
+### Follow
+
+Follow a user
+
+- For invalid token, send `400 - Bad Request` response.
+- For valid token:
+  - If user is not found, send `404 - Not Found` response.
+  - Add a follower to the specified user in the path parameter and send `200 - OK` response.
+
+Method: `POST` <br>
+Path: `/follow/:id`
+
+#### Request
+
+```sh
+curl \
+  -X POST \
+  http://localhost:1323/follow/58465b4ea6fe886d3215c6df \
+  -H "Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJleHAiOjE0ODEyNjUxMjgsImlkIjoiNTg0NjViNGVhNmZlODg2ZDMyMTVjNmRmIn0.1IsGGxko1qMCsKkJDQ1NfmrZ945XVC9uZpcvDnKwpL0"
+```
+
+#### Response
+
+`200 - OK`
+
+### Post
+
+Post a message to specified user
+
+- For invalid request payload, send `400 - Bad Request` response.
+- If user is not found, send `404 - Not Found` response.
+- Otherwise save post in the database and return it via `201 - Created` response.
+
+Method: `POST` <br>
+Path: `/posts`
+
+#### Request
+
+```sh
+curl \
+  -X POST \
+  http://localhost:1323/posts \
+  -H "Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJleHAiOjE0ODEyNjUxMjgsImlkIjoiNTg0NjViNGVhNmZlODg2ZDMyMTVjNmRmIn0.1IsGGxko1qMCsKkJDQ1NfmrZ945XVC9uZpcvDnKwpL0" \
+  -H "Content-Type: application/json" \
+  -d '{"to":"58465b4ea6fe886d3215c6df","message":"hello"}'
+```
+
+#### Response
+
+`201 - Created`
+
+```sh
+{
+  "id": "584661b9a6fe8871a3804cba",
+  "to": "58465b4ea6fe886d3215c6df",
+  "from": "58465b4ea6fe886d3215c6df",
+  "message": "hello"
+}
+```
+
+### Feed
+
+List most recent messages based on optional `page` and `limit` query parameters
+
+Method: `GET` <br>
+Path: `/feed?page=1&limit=5`
+
+#### Request
+
+```sh
+curl \
+  -X GET \
+  http://localhost:1323/feed \
+  -H "Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJleHAiOjE0ODEyNjUxMjgsImlkIjoiNTg0NjViNGVhNmZlODg2ZDMyMTVjNmRmIn0.1IsGGxko1qMCsKkJDQ1NfmrZ945XVC9uZpcvDnKwpL0"
+```
+
+#### Response
+
+`200 - OK`
+
+```sh
+[
+  {
+    "id": "584661b9a6fe8871a3804cba",
+    "to": "58465b4ea6fe886d3215c6df",
+    "from": "58465b4ea6fe886d3215c6df",
+    "message": "hello"
+  }
+]
+```
+
+## [Source Code]({{< source "twitter" >}})
+
+## Maintainers
+
+- [vishr](https://github.com/vishr)

website/layouts/_default/single.html

@@ -1,9 +1,9 @@
 {{ partial "head.html" . }}
-<body>
+<body class="docs">
 	{{ partial "topnav.html" . }}
   <div class="w3-container w3-content">
     {{ partial "sidenav.html" . }}
-    <div class="w3-main">
+    <div class="main">
       {{ partial "ad.html" }}
       <div class="w3-row-padding">
         <div class="w3-col s12 m10 l10">

website/layouts/index.html

@@ -1,12 +1,12 @@
 {{ partial "head.html" . }}
-<body>
+<body class="index">
 	{{ partial "topnav.html" . }}
   <div class="w3-hide-large">
     {{ partial "sidenav.html" . }}
   </div>
-	<div class="w3-container w3-content w3-padding-128">
+	<div class="w3-container w3-content main">
     {{ partial "ad.html" }}
-	  <div class="w3-row-padding">
+	  <div class="w3-row">
 			<div class="w3-col s12 m10 l10">
         <div class="hero">
           <h1>{{ .Site.Data.index.heading }}</h1>

website/layouts/single/single.html

@@ -1,8 +1,8 @@
 {{ partial "head.html" . }}
-<body>
+<body class="single">
 	{{ partial "topnav.html" . }}
-	<div class="w3-container w3-content w3-padding-64">
-	  <div class="w3-row-padding">
+	<div class="w3-container w3-content main">
+	  <div class="w3-row">
 			<div class="w3-col m10 l10">
         <h1>{{ .Title }}</h1>
         {{ .Content }}