还是三步骤创建EndPoint，创建Transport，调用请求
第一步创建transport
package Services
import (
"context"
"encoding/json"
"errors"
"github.com/tidwall/gjson"
"io/ioutil"
"net/http"
)
func DecodeAccessRequest(c context.Context, r *http.Request) (interface{}, error){
body,_:=ioutil.ReadAll(r.Body)
result:=gjson.Parse(string(body)) //第三方库解析json
if result.IsObject() { //如果是json就返回true
username:=result.Get("username")
userpass:=result.Get("userpass")
return AccessRequest{Username:username.String(),Userpass:userpass.String(),Method:r.Method},nil
}
return nil,errors.New("参数错误")
}
func EncodeAccessResponse(ctx context.Context, w http.ResponseWriter, response interface{}) error {
w.Header().Set("Content-type","application/json")
return json.NewEncoder(w).Encode(response) //返回一个bool值判断response是否可以正确的转化为json，不能则抛出异常，返回给调用方
}
在UserTransport中修改一下代码
package Services
import (
"context"
"encoding/json"
"errors"
mymux "github.com/gorilla/mux"
"gomicro/utils"
"net/http"
"strconv"
)
func DecodeUserRequest(c context.Context, r *http.Request) (interface{}, error) { //这个函数决定了使用哪个request来请求
vars := mymux.Vars(r)
if uid, ok := vars["uid"]; ok {
uid, _ := strconv.Atoi(uid)
return UserRequest{Uid: uid, Method: r.Method, Token: r.URL.Query().Get("token")}, nil //请求必须携带token过来，如果找不到这里返回空字符串，因为request访问的先后顺序是先DecodeUserRequest，再EncodeUserResponse再到我们的EndPoint，所以这里就已经给我们的request结构体存入了Token，那么我们EndPoint里面的request类型断言成UserRequest结构体实例后里面就有Token了
}
return nil, errors.New("参数错误")
}
func EncodeUserResponse(ctx context.Context, w http.ResponseWriter, response interface{}) error {
w.Header().Set("Content-type", "application/json")
return json.NewEncoder(w).Encode(response)
}
func MyErrorEncoder(ctx context.Context, err error, w http.ResponseWriter) {
contentType, body := "text/plain; charset=utf-8", []byte(err.Error())
w.Header().Set("Content-type", contentType) //设置请求头
if myerr, ok := err.(*utils.MyError); ok {
w.WriteHeader(myerr.Code)
w.Write(body)
} else {
w.WriteHeader(500)
w.Write(body)
}
}
创建Endpoint，这段是生成Token的代码，我这里先调用一下这段代码，拿到token后使用localhost:8080/user?token=token来访问我们的接口
package Services
import (
"context"
"fmt"
"github.com/dgrijalva/jwt-go"
"github.com/go-kit/kit/endpoint"
"time"
)
const secKey="123abc"//秘钥
type UserClaim struct {
Uname string `json:"username"`
jwt.StandardClaims
}
type IAccessService interface {
GetToken(uname string,upass string) (string,error)
}
type AccessService struct {}
func(this * AccessService) GetToken (uname string,upass string ) (string,error) {
if uname=="jerry" && upass=="123"{
userinfo:=&UserClaim{Uname:uname}
userinfo.ExpiresAt=time.Now().Add(time.Second*60).Unix() //设置60秒的过期时间
token_obj:=jwt.NewWithClaims(jwt.SigningMethodHS256,userinfo)
token,err:=token_obj.SignedString([]byte(secKey))
return token,err
}
return "",fmt.Errorf("error uname and password")
}
type AccessRequest struct {
Username string
Userpass string
Method string
}
type AccessResponse struct {
Status string
Token string
}
func AccessEndpoint(accessService IAccessService) endpoint.Endpoint {
return func(ctx context.Context, request interface{}) (response interface{}, err error) {
r:=request.(AccessRequest)
result:=AccessResponse{Status:"OK"}
if r.Method=="POST"{
token,err:=accessService.GetToken(r.Username,r.Userpass)
if err!=nil{
result.Status="error:"+err.Error()
}else{
result.Token=token
}
}
return result,nil
}
}
在UserEndPoint中增加CheckToken的中间件
package Services
import (
"context"
"fmt"
"github.com/dgrijalva/jwt-go"
"github.com/go-kit/kit/endpoint"
"github.com/go-kit/kit/log"
"golang.org/x/time/rate"
"gomicro/utils"
"strconv"
)
type UserRequest struct { //封装User请求结构体
Uid int `json:"uid"`
Method string
Token string
}
type UserResponse struct {
Result string `json:"result"`
}
//token验证中间件
func CheckTokenMiddleware() endpoint.Middleware { //Middleware type Middleware func(Endpoint) Endpoint
return func(next endpoint.Endpoint) endpoint.Endpoint { //Endpoint type Endpoint func(ctx context.Context, request interface{}) (response interface{}, err error)
return func(ctx context.Context, request interface{}) (response interface{}, err error) {
r := request.(UserRequest) //通过类型断言获取请求结构体
uc := UserClaim{}
//下面的r.Token是在代码DecodeUserRequest那里封装进去的
getToken, err := jwt.ParseWithClaims(r.Token, &uc, func(token *jwt.Token) (i interface{}, e error) {
return []byte(secKey), err
})
fmt.Println(err, 123)
if getToken != nil && getToken.Valid { //验证通过
newCtx := context.WithValue(ctx, "LoginUser", getToken.Claims.(*UserClaim).Uname)
return next(newCtx, request)
} else {
return nil, utils.NewMyError(403, "error token")
}
//logger.Log("method", r.Method, "event", "get user", "userid", r.Uid)
}
}
}
//日志中间件,每一个service都应该有自己的日志中间件
func UserServiceLogMiddleware(logger log.Logger) endpoint.Middleware { //Middleware type Middleware func(Endpoint) Endpoint
return func(next endpoint.Endpoint) endpoint.Endpoint { //Endpoint type Endpoint func(ctx context.Context, request interface{}) (response interface{}, err error)
return func(ctx context.Context, request interface{}) (response interface{}, err error) {
r := request.(UserRequest) //通过类型断言获取请求结构体
logger.Log("method", r.Method, "event", "get user", "userid", r.Uid)
return next(ctx, request)
}
}
}
//加入限流功能中间件
func RateLimit(limit *rate.Limiter) endpoint.Middleware { //Middleware type Middleware func(Endpoint) Endpoint
return func(next endpoint.Endpoint) endpoint.Endpoint { //Endpoint type Endpoint func(ctx context.Context, request interface{}) (response interface{}, err error)
return func(ctx context.Context, request interface{}) (response interface{}, err error) {
if !limit.Allow() {
return nil, utils.NewMyError(429, "toot many request")
}
return next(ctx, request) //执行endpoint
}
}
}
func GenUserEnPoint(userService IUserService) endpoint.Endpoint {
return func(ctx context.Context, request interface{}) (response interface{}, err error) {
r := request.(UserRequest) //通过类型断言获取请求结构体
fmt.Println("当前登录用户为", ctx.Value("LoginUser"))
result := "nothings"
if r.Method == "GET" {
result = userService.GetName(r.Uid) + strconv.Itoa(utils.ServicePort)
} else if r.Method == "DELETE" {
err := userService.DelUser(r.Uid)
if err != nil {
result = err.Error()
} else {
result = fmt.Sprintf("userid为%d的用户已删除", r.Uid)
}
}
return UserResponse{Result: result}, nil
}
}
调用checkToken中间件的代码
package main
import (
"flag"
"fmt"
kitlog "github.com/go-kit/kit/log"
httptransport "github.com/go-kit/kit/transport/http"
mymux "github.com/gorilla/mux"
"golang.org/x/time/rate"
"gomicro/Services"
"gomicro/utils"
"log"
"net/http"
"os"
"os/signal"
"strconv"
"syscall"
)
func main() {
name := flag.String("name", "", "服务名称")
port := flag.Int("port", 0, "服务端口")
flag.Parse()
if *name == "" {
log.Fatal("请指定服务名")
}
if *port == 0 {
log.Fatal("请指定端口")
}
var logger kitlog.Logger
{
logger = kitlog.NewLogfmtLogger(os.Stdout)
logger = kitlog.WithPrefix(logger, "mykit", "1.0")
logger = kitlog.WithPrefix(logger, "time", kitlog.DefaultTimestampUTC) //加上前缀时间
logger = kitlog.WithPrefix(logger, "caller", kitlog.DefaultCaller) //加上前缀，日志输出时的文件和第几行代码
}
utils.SetServiceNameAndPort(*name, *port) //设置服务名和端口
//用户服务
user := Services.UserService{}
limit := rate.NewLimiter(1, 5)
endp := Services.RateLimit(limit)(Services.UserServiceLogMiddleware(logger)(Services.CheckTokenMiddleware()(Services.GenUserEnPoint(user))))
//增加handler用于获取token
accessService := &Services.AccessService{}
accessServiceEndpoint := Services.AccessEndpoint(accessService)
accessHandler := httptransport.NewServer(accessServiceEndpoint, Services.DecodeAccessRequest, Services.EncodeAccessResponse)
options := []httptransport.ServerOption{
httptransport.ServerErrorEncoder(Services.MyErrorEncoder), //使用我们的自定义错误
}
serverHandler := httptransport.NewServer(endp, Services.DecodeUserRequest, Services.EncodeUserResponse, options...) //使用go kit创建server传入我们之前定义的两个解析函数
r := mymux.NewRouter()
//r.Handle(`/user/{uid:\d+}`, serverHandler) //这种写法支持多种请求方式
r.Methods("POST").Path("/access-token").Handler(accessHandler) //注册token获取的handler
r.Methods("GET", "DELETE").Path(`/user/{uid:\d+}`).Handler(serverHandler) //这种写法仅支持Get，限定只能Get请求
r.Methods("GET").Path("/health").HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
writer.Header().Set("Content-type", "application/json")
writer.Write([]byte(`{"status":"ok"}`))
})
errChan := make(chan error)
go func() {
utils.RegService() //调用注册服务程序
err := http.ListenAndServe(":"+strconv.Itoa(utils.ServicePort), r) //启动http服务
if err != nil {
log.Println(err)
errChan <- err
}
}()
go func() {
sigChan := make(chan os.Signal)
signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
errChan <- fmt.Errorf("%s", <-sigChan)
}()
getErr := <-errChan
utils.UnRegService()
log.Println(getErr)
}
使用postman测试接口
gjson适用于解析json的三方库，速度很快，可以取Github了解下
现在我们拿到了token，那么现在我们在访问的时候需要带上token去访问接口在UserRequest中新加一个Token字段用于请求认证
package Services
import (
"context"
"fmt"
"github.com/dgrijalva/jwt-go"
"github.com/go-kit/kit/endpoint"
"github.com/go-kit/kit/log"
"golang.org/x/time/rate"
"gomicro/utils"
"strconv"
)
type UserRequest struct { //封装User请求结构体
Uid int `json:"uid"`
Method string
Token string //新加的token字段，用于读取url中的token封装进来再传递给下一层的请求处理
}
type UserResponse struct {
Result string `json:"result"`
}
//token验证中间件
func CheckTokenMiddleware() endpoint.Middleware { //Middleware type Middleware func(Endpoint) Endpoint
return func(next endpoint.Endpoint) endpoint.Endpoint { //Endpoint type Endpoint func(ctx context.Context, request interface{}) (response interface{}, err error)
return func(ctx context.Context, request interface{}) (response interface{}, err error) {
r := request.(UserRequest) //通过类型断言获取请求结构体
uc := UserClaim{}
getToken, err := jwt.ParseWithClaims(r.Token, &uc, func(token *jwt.Token) (i interface{}, e error) { //验证token是否正确
return []byte(secKey), err
})
if getToken != nil && getToken.Valid { //验证通过
//这里很关键，验证通过后我们把用户名通过ctx传入到下一层的请求，标识当前用户已经通过验证，即GenUserEndPoint返回的endpoint方法
newCtx := context.WithValue(ctx, "LoginUser", getToken.Claims.(*UserClaim).Uname)
return next(newCtx, request)
} else {
return nil, utils.NewMyError(403, "error token")
}
//logger.Log("method", r.Method, "event", "get user", "userid", r.Uid)
}
}
}
//日志中间件,每一个service都应该有自己的日志中间件
func UserServiceLogMiddleware(logger log.Logger) endpoint.Middleware { //Middleware type Middleware func(Endpoint) Endpoint
return func(next endpoint.Endpoint) endpoint.Endpoint { //Endpoint type Endpoint func(ctx context.Context, request interface{}) (response interface{}, err error)
return func(ctx context.Context, request interface{}) (response interface{}, err error) {
r := request.(UserRequest) //通过类型断言获取请求结构体
logger.Log("method", r.Method, "event", "get user", "userid", r.Uid)
return next(ctx, request)
}
}
}
//加入限流功能中间件
func RateLimit(limit *rate.Limiter) endpoint.Middleware { //Middleware type Middleware func(Endpoint) Endpoint
return func(next endpoint.Endpoint) endpoint.Endpoint { //Endpoint type Endpoint func(ctx context.Context, request interface{}) (response interface{}, err error)
return func(ctx context.Context, request interface{}) (response interface{}, err error) {
if !limit.Allow() {
return nil, utils.NewMyError(429, "toot many request")
}
return next(ctx, request) //执行endpoint
}
}
}
func GenUserEnPoint(userService IUserService) endpoint.Endpoint {
return func(ctx context.Context, request interface{}) (response interface{}, err error) {
r := request.(UserRequest) //通过类型断言获取请求结构体
fmt.Println("当前登录用户为", ctx.Value("LoginUser")) //读取上面newCtx设置的用户name，判断能否处理请求，我这里是简写了，如果读不到应该拒绝处理
result := "nothings"
if r.Method == "GET" {
result = userService.GetName(r.Uid) + strconv.Itoa(utils.ServicePort)
} else if r.Method == "DELETE" {
err := userService.DelUser(r.Uid)
if err != nil {
result = err.Error()
} else {
result = fmt.Sprintf("userid为%d的用户已删除", r.Uid)
}
}
return UserResponse{Result: result}, nil
}
}
启动server后使用postman使用localhost:8080/user/101访问结果如下,因为url没有携带token所以报错了
接下来我们使用正确的方式再次访问
一般我們把token存入到Redis中防止用戶一直請求，也起到了缓存的作用
