使用Golang和MongoDB构建 RESTful API

记录一下创建 RESTful API 使用 Go 开发语言和 MongoDB 后台数据库

完整代码 Github

image

安装依赖

go get github.com/globalsign/mgo  // MongoDB的 Go 语言驱动
go get github.com/gorilla/mux   // Go语言的http路由库

API 结构预览

app.go

package main

import (
    "fmt"
    "net/http"

    "github.com/gorilla/mux"
)

func AllMovies(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

func FindMovie(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

func CreateMovie(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

func UpdateMovie(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

func DeleteMovie(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

func main() {
    r := mux.NewRouter()

    r.HandleFunc("/movies", AllMovies).Methods("GET")
    r.HandleFunc("/movies/{id}", FindMovie).Methods("GET")
    r.HandleFunc("/movies", CreateMovie).Methods("POST")
    r.HandleFunc("/movies", UpdateMovie).Methods("PUT")
    r.HandleFunc("/movies", DeleteMovie).Methods("DELETE")

    http.ListenAndServe(":8080", r)
}

随着后续路由的增加，需要重构一个这个文件，仿照 beego 的工程目录，我们也分别创建对应的 controllers
和 routes ,改造一下上面的代码

• 控制器

创建 controllers 文件夹和对应的文件 movies.go

movies.go

func AllMovies(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

func FindMovie(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

func CreateMovie(w http.ResponseWriter, t *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

func UpdateMovie(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

func DeleteMovie(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "not implemented !")
}

• 路由

创建一个 routes 文件夹，并创建对应的文件 routes.go

routes.go

package routes

import (
    "net/http"

    "github.com/coderminer/restful/controllers"
    "github.com/gorilla/mux"
)

type Route struct {
    Method     string
    Pattern    string
    Handler    http.HandlerFunc
    Middleware mux.MiddlewareFunc
}

var routes []Route

func init() {
    register("GET", "/movies", controllers.AllMovies, nil)
    register("GET", "/movies/{id}", controllers.FindMovie, nil)
    register("POST", "/movies", controllers.CreateMovie, nil)
    register("PUT", "/movies", controllers.UpdateMovie, nil)
    register("DELETE", "/movies", controllers.DeleteMovie, nil)
}

func NewRouter() *mux.Router {
    r := mux.NewRouter()
    for _, route := range routes {
        r.Methods(route.Method).
            Path(route.Pattern).
            Handler(route.Handler)
        if route.Middleware != nil {
            r.Use(route.Middleware)
        }
    }
    return r
}

func register(method, pattern string, handler http.HandlerFunc, middleware mux.MiddlewareFunc) {
    routes = append(routes, Route{method, pattern, handler, middleware})
}

重构后的 app.go

package main

import (
    "net/http"

    "github.com/coderminer/restful/routes"
)

func main() {
    r := routes.NewRouter()

    http.ListenAndServe(":8080", r)
}

Models

• 创建 models 文件夹和对应的文件 db.go (数据层)，封装对 MongoDB 的封装

package models

import (
    "log"

    "github.com/globalsign/mgo"
)

const (
    host   = "127.0.0.1:27017"
    source = "admin"
    user   = "user"
    pass   = "123456"
)

var globalS *mgo.Session

func init() {
    dialInfo := &mgo.DialInfo{
        Addrs:    []string{host},
        Source:   source,
        Username: user,
        Password: pass,
    }
    s, err := mgo.DialWithInfo(dialInfo)
    if err != nil {
        log.Fatalln("create session error ", err)
    }
    globalS = s
}

func connect(db, collection string) (*mgo.Session, *mgo.Collection) {
    s := globalS.Copy()
    c := s.DB(db).C(collection)
    return s, c
}

func Insert(db, collection string, docs ...interface{}) error {
    ms, c := connect(db, collection)
    defer ms.Close()
    return c.Insert(docs...)
}

func FindOne(db, collection string, query, selector, result interface{}) error {
    ms, c := connect(db, collection)
    defer ms.Close()
    return c.Find(query).Select(selector).One(result)
}

func FindAll(db, collection string, query, selector, result interface{}) error {
    ms, c := connect(db, collection)
    defer ms.Close()
    return c.Find(query).Select(selector).All(result)
}

func Update(db, collection string, query, update interface{}) error {
    ms, c := connect(db, collection)
    defer ms.Close()
    return c.Update(query, update)
}

func Remove(db, collection string, query interface{}) error {
    ms, c := connect(db, collection)
    defer ms.Close()
    return c.Remove(query)
}

• 业务逻辑层 models/movies.go

package models

import "github.com/globalsign/mgo/bson"

type Movies struct {
    Id          bson.ObjectId `bson:"_id" json:"id"`
    Name        string        `bson:"name" json:"name"`
    CoverImage  string        `bson:"cover_image" json:"cover_image"`
    Description string        `bson:"description" json:"description"`
}

const (
    db         = "Movies"
    collection = "MovieModel"
)

func (m *Movies) InsertMovie(movie Movies) error {
    return Insert(db, collection, movie)
}

func (m *Movies) FindAllMovies() ([]Movies, error) {
    var result []Movies
    err := FindAll(db, collection, nil, nil, &result)
    return result, err
}

func (m *Movies) FindMovieById(id string) (Movies, error) {
    var result Movies
    err := FindOne(db, collection, bson.M{"_id": bson.ObjectIdHex(id)}, nil, &result)
    return result, err
}

func (m *Movies) UpdateMovie(movie Movies) error {
    return Update(db, collection, bson.M{"_id": movie.Id}, movie)
}

func (m *Movies) RemoveMovie(id string) error {
    return Remove(db, collection, bson.M{"_id": bson.ObjectIdHex(id)})
}

控制器逻辑

• CreateMovie

func CreateMovie(w http.ResponseWriter, r *http.Request) {
    defer r.Body.Close()
    var movie models.Movies
    if err := json.NewDecoder(r.Body).Decode(&movie); err != nil {
        responseWithJson(w, http.StatusBadRequest, "Invalid request payload")
        return
    }
    movie.Id = bson.NewObjectId()
    if err := dao.InsertMovie(movie); err != nil {
        responseWithJson(w, http.StatusInternalServerError, err.Error())
        return
    }
    responseWithJson(w, http.StatusCreated, movie)
}

使用 Postman 或 curl 进行测试

• AllMovies

func AllMovies(w http.ResponseWriter, r *http.Request) {
    defer r.Body.Close()
    var movies []models.Movies
    movies, err := dao.FindAllMovies()
    if err != nil {
        responseWithJson(w, http.StatusInternalServerError, err.Error())
        return
    }
    responseWithJson(w, http.StatusOK, movies)

}

• FindMovie

func FindMovie(w http.ResponseWriter, r *http.Request) {
    vars := mux.Vars(r)
    id := vars["id"]
    result, err := dao.FindMovieById(id)
    if err != nil {
        responseWithJson(w, http.StatusInternalServerError, err.Error())
        return
    }
    responseWithJson(w, http.StatusOK, result)
}

http://127.0.0.1:8080/movies/5b45ef3a9d5e3e197c15e774

• UpdateMovie

func UpdateMovie(w http.ResponseWriter, r *http.Request) {
    defer r.Body.Close()
    var params models.Movies
    if err := json.NewDecoder(r.Body).Decode(&params); err != nil {
        responseWithJson(w, http.StatusBadRequest, "Invalid request payload")
        return
    }
    if err := dao.UpdateMovie(params); err != nil {
        responseWithJson(w, http.StatusInternalServerError, err.Error())
        return
    }
    responseWithJson(w, http.StatusOK, map[string]string{"result": "success"})
}

• DeleteMovie

func DeleteMovie(w http.ResponseWriter, r *http.Request) {
    vars := mux.Vars(r)
    id := vars["id"]
    if err := dao.RemoveMovie(id); err != nil {
        responseWithJson(w, http.StatusBadRequest, "Invalid request payload")
        return
    }

    responseWithJson(w, http.StatusOK, map[string]string{"result": "success"})
}