gistfile1.go

package main

import (
    "bufio"
    "fmt"
    "io"
    "io/ioutil"
    "net"
    "net/http"
    "net/http/httptest"
    "net/http/httputil"
)

func DoRequest(req *http.Request, c net.Conn) (*http.Response, error) {
    defer req.Body.Close()
    dumped, err := httputil.DumpRequestOut(req, false)
    if err != nil {
        return nil, err
    }
    if _, err = c.Write(dumped); err != nil {
        return nil, err
    }
    reader := bufio.NewReader(c)
    resp, err := http.ReadResponse(reader, req)
    if err != nil {
        return nil, err
    }
    if resp.StatusCode == 100 {
        io.Copy(c, req.Body)
        resp, err = http.ReadResponse(reader, req)
    }
    return resp, nil
}

var bodySize = 25

type FakeReader struct {
    readFrom bool
}

func (f *FakeReader) Read(p []byte) (int, error) {
    if !f.readFrom {
        f.readFrom = true
        return 25, nil
    }
    return 0, io.EOF
}

func main() {
    server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        if r.URL.Path == "/readbody" {
            data, err := ioutil.ReadAll(r.Body)
            if err != nil || len(data) != 25 {
                fmt.Println("Error reading body from request.")
            }
        }
        w.WriteHeader(200)
    }))

    c, err := net.Dial("tcp", server.Listener.Addr().String())
    if err != nil {
        fmt.Println("Error connecting to server", err)
        return
    }

    body := &FakeReader{readFrom: false}
    req, _ := http.NewRequest("POST", server.URL+"/readbody", body)
    req.Header.Add("Expect", "100-Continue")
    req.Header.Add("Content-Length", "25")
    req.ContentLength = 25
    resp, err := DoRequest(req, c)
    if err != nil {
        fmt.Println("Request error", err)
        return
    }
    if !body.readFrom {
        fmt.Println("Body should have been read, but wasn't.")
    }
    fmt.Println("Response status:", resp.StatusCode)

    body = &FakeReader{readFrom: false}
    req, _ = http.NewRequest("POST", server.URL+"/dontreadbody", body)
    req.Header.Add("Expect", "100-Continue")
    req.ContentLength = int64(bodySize)
    resp, err = DoRequest(req, c)
    if err != nil {
        fmt.Println("Request error", err)
        return
    }
    if body.readFrom {
        fmt.Println("Body shouldn't have been read, but was.")
    }
    fmt.Println("Response status:", resp.StatusCode)
}