使用bunrouter在Golang中创建HTTP路由

Gobunrouter教程展示了如何使用bunrouter在Golang中创建HTTP路由。

路由将一个HTTP动词（例如GET、POST、PUT、DELETE）和一个URL路径关联到一个处理函数。路由器是创建路由的对象；即它将HTTP请求映射到处理程序。

net/http

$ go version
go version go1.18.1 linux/amd64

我们使用Go版本1.18。

Gobunrouter简单例子

在第一个示例中，我们使用bunrouter设置了一个简单的服务器。

package main

import (
    "log"
    "net/http"

    "github.com/uptrace/bunrouter"
)

func main() {

    router := bunrouter.New()

    router.GET("/", func(w http.ResponseWriter, req bunrouter.Request) error {

        w.Write([]byte("index"))
        return nil
    })

    log.Println("listening on http://localhost:8080")
    log.Println(http.ListenAndServe(":8080", router))
}

服务器用一条短消息响应GET请求。

import (
    "log"
    "net/http"

    "github.com/uptrace/bunrouter"
)

github.com/uptrace/bunrouter

router := bunrouter.New()

创建了一个新的bunrouter。

router.GET("/", func(w http.ResponseWriter, req bunrouter.Request) error {

    w.Write([]byte("index"))
    return nil
})

我们创建一个GET路由。匿名处理函数以“索引”消息响应。

Gobunrouternotfound处理程序

在下一个示例中，我们设置了notfound处理程序。它用于处理没有路由的请求。

package main

import (
    "fmt"
    "log"
    "net/http"

    "github.com/uptrace/bunrouter"
)

func main() {

    router := bunrouter.New(
        bunrouter.WithNotFoundHandler(notFoundHandler),
    )

    router.GET("/hello", func(w http.ResponseWriter, req bunrouter.Request) error {

        fmt.Fprintf(w, "hello")
        return nil
    })

    log.Println("listening on http://localhost:8080")
    log.Println(http.ListenAndServe(":8080", router))
}

func notFoundHandler(w http.ResponseWriter, req bunrouter.Request) error {

    w.WriteHeader(http.StatusNotFound)

    fmt.Fprintf(w, "404 - failed to find %s", req.URL.Path)
    return nil
}

notFoundHandler

router := bunrouter.New(
    bunrouter.WithNotFoundHandler(notFoundHandler),
)

WithNotFoundHandler

func notFoundHandler(w http.ResponseWriter, req bunrouter.Request) error {

    w.WriteHeader(http.StatusNotFound)

    fmt.Fprintf(w, "404 - failed to find %s", req.URL.Path)
    return nil
}

notFoundHandler

$ curl localhost:8080/about
404 - failed to find /about

不允许的方法

HTTP405MethodNotAllowed响应状态代码表示服务器知道请求方法，但目标资源不支持此方法。

例如，我们有一个只响应GET请求的路由。如果我们发送一个POST请求，服务器可以响应405MethodNotAllowed消息。默认情况下，bunrouter在这种情况下什么都不做。

package main

import (
    "fmt"
    "log"
    "net/http"

    "github.com/uptrace/bunrouter"
)

func main() {

    router := bunrouter.New(bunrouter.WithMethodNotAllowedHandler(methodNotAllowedHandler))

    router.GET("/", func(w http.ResponseWriter, req bunrouter.Request) error {

        fmt.Fprintln(w, "index")

        return nil
    })

    log.Println("listening on http://localhost:8080")
    log.Println(http.ListenAndServe(":8080", router))
}

func methodNotAllowedHandler(w http.ResponseWriter, req bunrouter.Request) error {

    w.WriteHeader(http.StatusMethodNotAllowed)

    fmt.Fprintln(w, "405 - method not allowed")
    return nil
}

bunrouter.WithMethodNotAllowedHandler

$  curl localhost:8080/
index
$ curl localhost:8080/ -d "name=Peter"
405 - method not allowed

去bunrouterPOST请求

HTTPPOST方法向服务器发送数据。它通常在上传文件或提交完整的Web表单时使用。

package main

import (
    "fmt"
    "log"
    "net/http"

    "github.com/uptrace/bunrouter"
)

func main() {

    router := bunrouter.New()

    router.GET("/", func(w http.ResponseWriter, req bunrouter.Request) error {

        fmt.Fprintln(w, "index")

        return nil
    })

    router.POST("/", func(w http.ResponseWriter, req bunrouter.Request) error {

        err := req.ParseForm()

        if err != nil {
            http.Error(w, fmt.Sprint(err), http.StatusUnprocessableEntity)
        }

        fmt.Fprintln(w, req.Form)

        return nil
    })

    log.Println("listening on http://localhost:8080")
    log.Println(http.ListenAndServe(":8080", router))
}

该示例处理POST请求。

err := req.ParseForm()

ParseFormReq.Form

if err != nil {
    http.Error(w, fmt.Sprint(err), http.StatusUnprocessableEntity)
}

http.Error

路由器组

路由功能可以组织成组。

package main

import (
    "fmt"
    "log"
    "net/http"

    "github.com/uptrace/bunrouter"
)

func main() {

    router := bunrouter.New()

    router.WithGroup("/api/", func(group *bunrouter.Group) {

        group.GET("/index", index)
        group.GET("/hello", hello)

    })

    router.WithGroup("/api2/", func(group *bunrouter.Group) {

        group.GET("/index", index2)
        group.GET("/hello", hello2)

    })

    log.Println("listening on http://localhost:8080")
    log.Println(http.ListenAndServe(":8080", router))
}

func index(w http.ResponseWriter, req bunrouter.Request) error {

    fmt.Fprintln(w, "index")
    return nil
}

func hello(w http.ResponseWriter, req bunrouter.Request) error {

    fmt.Fprintln(w, "hello")
    return nil
}

func index2(w http.ResponseWriter, req bunrouter.Request) error {

    fmt.Fprintln(w, "index2")
    return nil
}

func hello2(w http.ResponseWriter, req bunrouter.Request) error {

    fmt.Fprintln(w, "hello2")
    return nil
}

/api//api2/

router.WithGroup("/api/", func(group *bunrouter.Group) {

    group.GET("/index", index)
    group.GET("/hello", hello)

})

WithGroup

$ curl localhost:8080/api/index
index
$ curl localhost:8080/api/hello
hello
$ curl localhost:8080/api2/hello
hello2
$ curl localhost:8080/api2/index
index2

在本教程中，我们使用了bunrouter。

列出所有Go教程。