Golang http 开启 gzip

一. 测试代码

package gzip

import (
    "compress/gzip"
    "fmt"
    "io/ioutil"
    "log"
    "net/http"
)

func RequestGzip(enable bool) (int, error) {
    client := http.Client{}
    req, err := http.NewRequest("GET", "http://www.baidu.com", nil)
    if enable { // 请求 header 添加 gzip
        req.Header.Add("Content-Encoding", "gzip")
        req.Header.Add("Accept-Encoding", "gzip")
    }
    resp, err := client.Do(req)
    if err != nil {
        fmt.Println("client.Do Error:", err)
        return 0, err
    }
    defer resp.Body.Close()

    body, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        fmt.Println("ioutil.ReadAll Error", err)
        return 0, err
    }
    return len(body), nil
}

// client 解析 gzip 返回
func ClientUncompress() {
    client := http.Client{}
    req, err := http.NewRequest("GET", "http://www.baidu.com", nil)
    req.Header.Add("Content-Encoding", "gzip")
    req.Header.Add("Accept-Encoding", "gzip")
    resp, err := client.Do(req)
    if err != nil {
        log.Fatal(err)
    }
    defer resp.Body.Close()

    var buf [1024 * 1024]byte
    reader, err := gzip.NewReader(resp.Body)
    if err != nil {
        log.Fatal(err)
    }
    _, err = reader.Read(buf[:])
    if err != nil {
        log.Fatal(err)
    }
    reader.Close()
}

// client 正常解析返回
func ClientNormal() {
    client := http.Client{}
    req, err := http.NewRequest("GET", "http://www.baidu.com", nil)
    resp, err := client.Do(req)
    if err != nil {
        log.Fatal(err)
    }
    defer resp.Body.Close()

    var buf [1024 * 1024]byte
    _, err = resp.Body.Read(buf[:])
    if err != nil {
        log.Fatal(err)
    }
    resp.Body.Close()
}

1.1. http 开启 gzip 数据大小对比

package gzip

import (
    "testing"
)

func TestRequestGzip(t *testing.T) {
    length, err := RequestGzip(true) // 开启 gzip
    if err != nil {
        t.Error(err)
    }
    t.Logf("Request with gzip length: %d", length)

    length, err = RequestGzip(false) // 未开启 gzip
    if err != nil {
        t.Error(err)
    }
    t.Logf("Request without gzip length: %d", length)
}

go test -v .
=== RUN   TestRequestGzip
--- PASS: TestRequestGzip (0.05s)
    gzip_test.go:12: Request with gzip length: 32168
    gzip_test.go:18: Request without gzip length: 118315
PASS

可以看到返回的数据压缩前大小 118315，压缩后 32168。

1.2. http 开启 gzip benchmark 对比

压缩后数据量变小了，但解压缩会稍稍降低性能。

package gzip

import "testing"

func BenchmarkClientUncompress(b *testing.B) {
    for i := 0; i < b.N; i++ {
        ClientUncompress()
    }
}

func BenchmarkClientNormal(b *testing.B) {
    for i := 0; i < b.N; i++ {
        ClientNormal()
    }
}

go test -bench=. -run=none
goos: darwin
goarch: amd64
BenchmarkClientUncompress-8          100      19972186 ns/op
BenchmarkClientNormal-8              100      17922070 ns/op
PASS

参考

https://golang.org/pkg/compress/gzip/