Kratos 大乱炖 —— 整合其他Web框架：Gin、FastHttp、Hertz
Kratos默认的RPC框架使用的是gRPC，支持REST和protobuf两种通讯协议。其API都是使用protobuf定义的，REST协议是通过grpc-gateway转译实现的。使用protobuf定义API是具有极大优点的，具有很强的可读性、可维护性，以及工程性。工程再大，人员再多，也不会乱。
一切看起来都是很美好的。那么，问题来了，我们现在使用的是其他的Web框架，迁移就会有成本，有风险，不可能一下子就把历史存在的代码一口气转换过来到Kratos框架。那我可以在Kratos中整合其他的Web框架做过渡吗？答案是：可以的。Kratos是基于的插件化设计，万物皆可插。
我整合了主流的Gin和FastHttp。顺便把字节跳动的Hertz也尝试着整合了一下。整合之后，使用起来毫无违和感。
Gin
Gin 是用 Go 编写的一个 Web 应用框架，对比其它主流的同类框架，他有更好的性能和更快的路由。由于其本身只是在官方 net/http 包的基础上做的完善，所以理解和上手很平滑。
封装的代码如下：
package gin
import (
"context"
"crypto/tls"
"net/http"
"net/url"
"time"
"github.com/gin-gonic/gin"
"github.com/go-kratos/kratos/v2/errors"
"github.com/go-kratos/kratos/v2/log"
"github.com/go-kratos/kratos/v2/middleware"
"github.com/go-kratos/kratos/v2/transport"
kHttp "github.com/go-kratos/kratos/v2/transport/http"
)
var (
_ transport.Server = (*Server)(nil)
_ transport.Endpointer = (*Server)(nil)
)
type Server struct {
*gin.Engine
server *http.Server
tlsConf *tls.Config
endpoint *url.URL
timeout time.Duration
addr string
err error
filters []kHttp.FilterFunc
ms []middleware.Middleware
dec kHttp.DecodeRequestFunc
enc kHttp.EncodeResponseFunc
ene kHttp.EncodeErrorFunc
}
func NewServer(opts ...ServerOption) *Server {
srv := &Server{
timeout: 1 * time.Second,
dec: kHttp.DefaultRequestDecoder,
enc: kHttp.DefaultResponseEncoder,
ene: kHttp.DefaultErrorEncoder,
}
srv.init(opts...)
return srv
}
func (s *Server) init(opts ...ServerOption) {
s.Engine = gin.Default()
for _, o := range opts {
o(s)
}
s.server = &http.Server{
Addr: s.addr,
Handler: s.Engine,
TLSConfig: s.tlsConf,
}
s.endpoint, _ = url.Parse(s.addr)
}
func (s *Server) Endpoint() (*url.URL, error) {
return s.endpoint, nil
}
func (s *Server) Start(ctx context.Context) error {
log.Infof("[GIN] server listening on: %s", s.addr)
var err error
if s.tlsConf != nil {
err = s.server.ListenAndServeTLS("", "")
} else {
err = s.server.ListenAndServe()
}
if !errors.Is(err, http.ErrServerClosed) {
return err
}
return nil
}
func (s *Server) Stop(ctx context.Context) error {
log.Info("[GIN] server stopping")
return s.server.Shutdown(ctx)
}
func (s *Server) ServeHTTP(res http.ResponseWriter, req *http.Request) {
s.Engine.ServeHTTP(res, req)
}
应用的代码如下：
package gin
import (
"context"
"math/rand"
"strconv"
"github.com/gin-gonic/gin"
transport "github.com/tx7do/kratos-transport/gin"
api "github.com/tx7do/kratos-transport/_example/api/protobuf"
)
func main() {
ctx := context.Background()
srv := transport.NewServer(
WithAddress(":8800"),
)
srv.Use(gin.Recovery())
srv.Use(gin.Logger())
srv.GET("/login/*param", func(c *gin.Context) {
if len(c.Params.ByName("param")) > 1 {
c.AbortWithStatus(404)
return
}
c.String(200, "Hello World!")
})
srv.GET("/hygrothermograph", func(c *gin.Context) {
var out api.Hygrothermograph
out.Humidity = strconv.FormatInt(int64(rand.Intn(100)), 10)
out.Temperature = strconv.FormatInt(int64(rand.Intn(100)), 10)
c.JSON(200, &out)
})
if err := srv.Start(ctx); err != nil {
panic(err)
}
defer func() {
if err := srv.Stop(ctx); err != nil {
t.Errorf("expected nil got %v", err)
}
}()
}
FastHttp
FastHTTP是golang下的一个http框架，顾名思义，与原生的http实现相比，它的特点在于快，按照官网的说法，它的客户端和服务端性能比原生有了十倍的提升。
它的高性能主要源自于“复用”，通过服务协程和内存变量的复用，节省了大量资源分配的成本。
封装的代码如下：
package fasthttp
import (
"context"
"crypto/tls"
"net/http"
"net/url"
"time"
"github.com/fasthttp/router"
"github.com/valyala/fasthttp"
"github.com/go-kratos/kratos/v2/errors"
"github.com/go-kratos/kratos/v2/log"
"github.com/go-kratos/kratos/v2/middleware"
"github.com/go-kratos/kratos/v2/transport"
kHttp "github.com/go-kratos/kratos/v2/transport/http"
)
var (
_ transport.Server = (*Server)(nil)
_ transport.Endpointer = (*Server)(nil)
)
type Server struct {
*fasthttp.Server
tlsConf *tls.Config
endpoint *url.URL
timeout time.Duration
addr string
err error
filters []FilterFunc
ms []middleware.Middleware
dec kHttp.DecodeRequestFunc
enc kHttp.EncodeResponseFunc
ene kHttp.EncodeErrorFunc
strictSlash bool
router *router.Router
}
func NewServer(opts ...ServerOption) *Server {
srv := &Server{
timeout: 1 * time.Second,
dec: kHttp.DefaultRequestDecoder,
enc: kHttp.DefaultResponseEncoder,
ene: kHttp.DefaultErrorEncoder,
strictSlash: true,
router: router.New(),
}
srv.init(opts...)
return srv
}
func (s *Server) init(opts ...ServerOption) {
for _, o := range opts {
o(s)
}
s.Server = &fasthttp.Server{
TLSConfig: s.tlsConf,
Handler: FilterChain(s.filters...)(s.router.Handler),
}
s.router.RedirectTrailingSlash = s.strictSlash
s.endpoint, _ = url.Parse(s.addr)
}
func (s *Server) Endpoint() (*url.URL, error) {
return s.endpoint, nil
}
func (s *Server) Start(ctx context.Context) error {
log.Infof("[fasthttp] server listening on: %s", s.addr)
var err error
if s.tlsConf != nil {
err = s.Server.ListenAndServeTLS(s.addr, "", "")
} else {
err = s.Server.ListenAndServe(s.addr)
}
if !errors.Is(err, http.ErrServerClosed) {
return err
}
return nil
}
func (s *Server) Stop(_ context.Context) error {
log.Info("[fasthttp] server stopping")
return s.Server.Shutdown()
}
func (s *Server) Handle(method, path string, handler fasthttp.RequestHandler) {
s.router.Handle(method, path, handler)
}
func (s *Server) GET(path string, handler fasthttp.RequestHandler) {
s.Handle(fasthttp.MethodGet, path, handler)
}
func (s *Server) HEAD(path string, handler fasthttp.RequestHandler) {
s.Handle(fasthttp.MethodHead, path, handler)
}
func (s *Server) POST(path string, handler fasthttp.RequestHandler) {
s.Handle(fasthttp.MethodPost, path, handler)
}
func (s *Server) PUT(path string, handler fasthttp.RequestHandler) {
s.Handle(fasthttp.MethodPut, path, handler)
}
func (s *Server) PATCH(path string, handler fasthttp.RequestHandler) {
s.Handle(fasthttp.MethodPatch, path, handler)
}
func (s *Server) DELETE(path string, handler fasthttp.RequestHandler) {
s.Handle(fasthttp.MethodDelete, path, handler)
}
func (s *Server) CONNECT(path string, handler fasthttp.RequestHandler) {
s.Handle(fasthttp.MethodConnect, path, handler)
}
func (s *Server) OPTIONS(path string, handler fasthttp.RequestHandler) {
s.Handle(fasthttp.MethodOptions, path, handler)
}
func (s *Server) TRACE(path string, handler fasthttp.RequestHandler) {
s.Handle(fasthttp.MethodTrace, path, handler)
}
应用的代码如下：
package fasthttp
import (
"context"
"encoding/json"
"math/rand"
"strconv"
"github.com/valyala/fasthttp"
transport "github.com/tx7do/kratos-transport/fasthttp"
api "github.com/tx7do/kratos-transport/_example/api/protobuf"
)
func main() {
ctx := context.Background()
srv := transport.NewServer(
WithAddress(":8800"),
)
srv.GET("/login/*param", func(c *fasthttp.RequestCtx) {
_, _ = c.WriteString("Hello World!")
})
srv.GET("/hygrothermograph", func(c *fasthttp.RequestCtx) {
var out api.Hygrothermograph
out.Humidity = strconv.FormatInt(int64(rand.Intn(100)), 10)
out.Temperature = strconv.FormatInt(int64(rand.Intn(100)), 10)
_ = json.NewEncoder(c.Response.BodyWriter()).Encode(&out)
})
if err := srv.Start(ctx); err != nil {
panic(err)
}
defer func() {
if err := srv.Stop(ctx); err != nil {
t.Errorf("expected nil got %v", err)
}
}()
}
Hertz
Hertz[həːts] 是一个 Golang 微服务 HTTP 框架，在设计之初参考了其他开源框架 fasthttp、gin、echo 的优势， 并结合字节跳动内部的需求，使其具有高易用性、高性能、高扩展性等特点，目前在字节跳动内部已广泛使用。 如今越来越多的微服务选择使用 Golang，如果对微服务性能有要求，又希望框架能够充分满足内部的可定制化需求，Hertz 会是一个不错的选择。
封装的代码如下：
package hertz
import (
"context"
"crypto/tls"
"net/url"
"time"
hertz "github.com/cloudwego/hertz/pkg/app/server"
"github.com/go-kratos/kratos/v2/log"
"github.com/go-kratos/kratos/v2/middleware"
"github.com/go-kratos/kratos/v2/transport"
kHttp "github.com/go-kratos/kratos/v2/transport/http"
)
var (
_ transport.Server = (*Server)(nil)
_ transport.Endpointer = (*Server)(nil)
)
type Server struct {
*hertz.Hertz
tlsConf *tls.Config
endpoint *url.URL
timeout time.Duration
addr string
err error
filters []kHttp.FilterFunc
ms []middleware.Middleware
dec kHttp.DecodeRequestFunc
enc kHttp.EncodeResponseFunc
ene kHttp.EncodeErrorFunc
}
func NewServer(opts ...ServerOption) *Server {
srv := &Server{
timeout: 1 * time.Second,
dec: kHttp.DefaultRequestDecoder,
enc: kHttp.DefaultResponseEncoder,
ene: kHttp.DefaultErrorEncoder,
}
srv.init(opts...)
return srv
}
func (s *Server) init(opts ...ServerOption) {
for _, o := range opts {
o(s)
}
s.Hertz = hertz.Default(hertz.WithHostPorts(s.addr), hertz.WithTLS(s.tlsConf))
s.endpoint, _ = url.Parse(s.addr)
}
func (s *Server) Endpoint() (*url.URL, error) {
return s.endpoint, nil
}
func (s *Server) Start(ctx context.Context) error {
log.Infof("[hertz] server listening on: %s", s.addr)
return s.Hertz.Run()
}
func (s *Server) Stop(ctx context.Context) error {
log.Info("[hertz] server stopping")
return s.Hertz.Shutdown(ctx)
}
应用的代码如下：
package hertz
import (
"context"
"math/rand"
"strconv"
"github.com/cloudwego/hertz/pkg/app"
transport "github.com/tx7do/kratos-transport/hertz"
api "github.com/tx7do/kratos-transport/_example/api/protobuf"
)
func TestServer(t *testing.T) {
ctx := context.Background()
srv := transport.NewServer(
WithAddress("127.0.0.1:8800"),
)
srv.GET("/login/*param", func(ctx context.Context, c *app.RequestContext) {
if len(c.Params.ByName("param")) > 1 {
c.AbortWithStatus(404)
return
}
c.String(200, "Hello World!")
})
srv.GET("/hygrothermograph", func(ctx context.Context, c *app.RequestContext) {
var out api.Hygrothermograph
out.Humidity = strconv.FormatInt(int64(rand.Intn(100)), 10)
out.Temperature = strconv.FormatInt(int64(rand.Intn(100)), 10)
c.JSON(200, &out)
})
if err := srv.Start(ctx); err != nil {
panic(err)
}
defer func() {
if err := srv.Stop(ctx); err != nil {
t.Errorf("expected nil got %v", err)
}
}()
}
