Go實現簡單的RESTful_API

何為RESTful API

A RESTful API is an application program interface (API) that uses HTTP requests to GET, PUT, POST and DELETE data.

A RESTful API – also referred to as a RESTful web service – is based on representational state transfer (REST) technology, an architectural style and approach to communications often used in web services development.

Wikipedia: 表征性狀態傳輸（英文：Representational State Transfer，簡稱REST）是Roy Fielding博士于2000年在他的博士論文中提出來的一種軟件架構風格。
Roy Fielding是HTTP協議（1.0版和1.1版）的主要設計者，事實上HTTP 1.1規范正是基于REST架構風格的指導原理來設計的。需要注意的是，REST是一種設計風格而不是標準，如果一個架構符合REST原則，我們就稱它為RESTful架構。

gorilla/mux

golang自帶的http.SeverMux路由實現簡單,本質是一個map[string]Handler,是請求路徑與該路徑對應的處理函數的映射關系。實現簡單功能也比較單一：

1. 不支持正則路由， 這個是比較致命的
2. 只支持路徑匹配，不支持按照Method，header，host等信息匹配，所以也就沒法實現RESTful架構

安裝第三方安裝包

go get -u github.com/gorilla/mux

實現

1. 定義結構體，用戶構造json

type Person struct {ID        string   `json:"id,omitemty"`Firstname string   `json:"firstname,omitempty"`Lastname  string   `json:"lastname,omitempty"`Address   *Address `json:"address,omitempty"`
}type Address struct {City     string `json:"city,omitempty"`Province string `json:"province,omitempty"`
}

1. 接下來，定義一個全局變量，用于存儲資源(數據)：

var people []Person

1. Get

獲取所有person，這里我們叫people：

func GetPeople(w http.ResponseWriter, req *http.Request) {json.NewEncoder(w).Encode(people)
}

根據id獲取person：

func GetPerson(w http.ResponseWriter, req *http.Request) {params := mux.Vars(req)for _, item := range people {if item.ID == params["id"] {json.NewEncoder(w).Encode(item)return}}json.NewEncoder(w).Encode(people)
}

1. post

同樣可以，通過post操作向服務器添加數據：

func PostPerson(w http.ResponseWriter, req *http.Request) {params := mux.Vars(req)var person Person_ = json.NewDecoder(req.Body).Decode(&person)person.ID = params["id"]people = append(people, person)json.NewEncoder(w).Encode(people)
}

1. Delete

func DeletePerson(w http.ResponseWriter, req *http.Request) {params := mux.Vars(req)for index, item := range people {if item.ID == params["id"] {people = append(people[:index], people[index+1:]...)break}}json.NewEncoder(w).Encode(people)
}

完整代碼

package mainimport ("encoding/json""log""net/http""github.com/gorilla/mux"
)type Person struct {ID        string   `json:"id,omitemty"`Firstname string   `json:"firstname,omitempty"`Lastname  string   `json:"lastname,omitempty"`Address   *Address `json:"address,omitempty"`
}type Address struct {City     string `json:"city,omitempty"`Province string `json:"province,omitempty"`
}var people []Person

// *******************************************************************>>
// Get
// 獲取所有person
func GetPeople(w http.ResponseWriter, req *http.Request) {json.NewEncoder(w).Encode(people)
}

// 根據id獲取person
func GetPerson(w http.ResponseWriter, req *http.Request) {params := mux.Vars(req)for _, item := range people {if item.ID == params["id"] {json.NewEncoder(w).Encode(item)return}}json.NewEncoder(w).Encode(people)
}

// <<*******************************************************************

// *******************************************************************>>
// Post
// 通過post操作向服務器添加數據
func PostPerson(w http.ResponseWriter, req *http.Request) {params := mux.Vars(req)var person Person_ = json.NewDecoder(req.Body).Decode(&person)person.ID = params["id"]people = append(people, person)json.NewEncoder(w).Encode(people)
}

// <<*******************************************************************

// *******************************************************************>>
// Delete
// 根據id進行刪除操作
func DeletePerson(w http.ResponseWriter, req *http.Request) {params := mux.Vars(req)for index, item := range people {if item.ID == params["id"] {people = append(people[:index], people[index+1:]...)break}}json.NewEncoder(w).Encode(people)
}

// <<*******************************************************************func main() {people = append(people, Person{ID: "1", Firstname: "xi", Lastname: "dada", Address: &Address{City: "Shenyang", Province: "Liaoning"}})people = append(people, Person{ID: "2", Firstname: "li", Lastname: "xiansheng", Address: &Address{City: "Changchun", Province: "Jinlin"}}) // Get handle function:router := mux.NewRouter()router.HandleFunc("/people", GetPeople).Methods("GET")router.HandleFunc("/people/{id}", GetPerson).Methods("GET") // Post handle functionrouter.HandleFunc("/people/{id}", PostPerson).Methods("POST") // Delete handle function:router.HandleFunc("/people/{id}", DeletePerson).Methods("DELETE") // 啟動 API端口9899log.Fatal(http.ListenAndServe(":9899", router))
}

運行：

go run ***.go

或者編譯成二進制運行

go build ***.go

然后在瀏覽器中測試

http://localhost:9899/people

[{"id":"1","firstname":"xi","lastname":"dada","address":{"city":"Shenyang","province":"Liaoning"}},{"id":"2","firstname":"li","lastname":"xiansheng","address":{"city":"Changchun","province":"Jinlin"}}
]