Go 语言基础及实战案例｜ 字节跳动青训营笔记

一、本堂课重点内容：

Go 语言学习背景介绍

Go 语言基础语言详细讲解

  1. 开发环境
  2. 基础语法
  3. 标准库

Go 语言实战

  1. 项目一：猜谜游戏
  2. 项目二：命令行词典
  3. 项目三：SOCKS5 代理

二、详细知识点介绍：

Go 语言学习背景介绍

  1. 高性能、高并发
  2. 语法简单、学习曲线平缓
  3. 丰富的标准库
  4. 完善的工具链
  5. 静态链接
  6. 快速编译
  7. 跨平台
  8. 垃圾回收

Go 语言基础语言详细讲解

  • 开发环境

开发环境选择了VScode，安装了Golang，顺利运行样例程序Hello World

  • 基础语法
  1. 变量
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var a="initial"
g:=a+"apple"
const s string = "constant"
const h = 500000
  1. 数组
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var a[5]int
b:=[5]int{1,2,3,4,5}
var  towD [2][3]int
  1. 切片
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s:=make([]string,3)
fmt.Println(s[2:5])
fmt.Println(s[:5])
fmt.Println(s[2:])
good:=[]string{"g","o","o","d"}
  1. map
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m:=make(map[string]int)
m["one"]=1

r,ok:=m["unknow"]
fmt.Println(r,ok) //0 false
  1. range
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nums:=[]int{2,3,4}
for i,num := range nums{
    if num==2{
        fmt.Println("index:",i,"num:",num) //index:0 num:2
    }
}
m:=map[string]string{"a":"A","b":"B"}
for k,v :=range m{
    fmt.Println(k,v) //b B;a A
}

三、实践练习例子：

项目一：猜谜游戏

  • 生成随机数
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rand.seed(time.Now().UnixNano())//很重要，需用时间戳来初始化随机数种子，否则生成伪随机数
secretNumber:=rand.Intn(maxNum)
  • 读取用户输入
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reader := bufio.NewReader(os.Stdin)  //输入流
input, err := reader.ReadString('\n')
input = strings.Trim(input, "\r\n")  //去除回车
guess, err := strconv.Atoi(input)  //字符转数字
  • 实现游戏循环
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for {
    //···
}
  • 实现判断逻辑
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if {
    //···
}else{
    //···
}

项目二：命令行词典

  • 抓包

进入官网彩云小译 - 在线翻译 (caiyunapp.com)

右键检查-Network-dict (请求 URL: https://api.interpreter.caiyunai.com/v1/dict 请求方法: POST)

uTools_1673778139893

uTools_1673778815476

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package main

import (
    "fmt"
    "io/ioutil"
    "log"
    "net/http"
    "strings"
)

func main() {
    client := &http.Client{}
    var data = strings.NewReader(`{"trans_type":"en2zh","source":"abandon"}`)
    req, err := http.NewRequest("POST", "https://api.interpreter.caiyunai.com/v1/dict", data)
    if err != nil {
        log.Fatal(err)
    }
    req.Header.Set("authority", "api.interpreter.caiyunai.com")
    req.Header.Set("accept", "application/json, text/plain, */*")
    req.Header.Set("accept-language", "zh-CN,zh;q=0.9,en;q=0.8,en-GB;q=0.7,en-US;q=0.6")
    req.Header.Set("app-name", "xy")
    req.Header.Set("content-type", "application/json;charset=UTF-8")
    req.Header.Set("device-id", "")
    req.Header.Set("origin", "https://fanyi.caiyunapp.com")
    req.Header.Set("os-type", "web")
    req.Header.Set("os-version", "")
    req.Header.Set("referer", "https://fanyi.caiyunapp.com/")
    req.Header.Set("sec-ch-ua", `"Not?A_Brand";v="8", "Chromium";v="108", "Microsoft Edge";v="108"`)
    req.Header.Set("sec-ch-ua-mobile", "?0")
    req.Header.Set("sec-ch-ua-platform", `"Windows"`)
    req.Header.Set("sec-fetch-dest", "empty")
    req.Header.Set("sec-fetch-mode", "cors")
    req.Header.Set("sec-fetch-site", "cross-site")
    req.Header.Set("user-agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36 Edg/108.0.1462.76")
    req.Header.Set("x-authorization", "token:qgemv4jr1y38jyq6vhvi")
    resp, err := client.Do(req)
    if err != nil {
        log.Fatal(err)
    }
    defer resp.Body.Close()
    bodyText, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("%s\n", bodyText)
}
  • 生成request body
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type DictRequest struct {
    TransType string `json:"trans_type"`
    Source    string `json:"source"`
    UserID    string `json:"user_id"`
}
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type DictResponse struct {
    Rc   int `json:"rc"`
    Wiki struct {
        KnownInLaguages int `json:"known_in_laguages"`
        Description     struct {
            Source string      `json:"source"`
            Target interface{} `json:"target"`
        } `json:"description"`
        ID   string `json:"id"`
        Item struct {
            Source string `json:"source"`
            Target string `json:"target"`
        } `json:"item"`
        ImageURL  string `json:"image_url"`
        IsSubject string `json:"is_subject"`
        Sitelink  string `json:"sitelink"`
    } `json:"wiki"`
    Dictionary struct {
        Prons struct {
            EnUs string `json:"en-us"`
            En   string `json:"en"`
        } `json:"prons"`
        Explanations []string      `json:"explanations"`
        Synonym      []string      `json:"synonym"`
        Antonym      []string      `json:"antonym"`
        WqxExample   [][]string    `json:"wqx_example"`
        Entry        string        `json:"entry"`
        Type         string        `json:"type"`
        Related      []interface{} `json:"related"`
        Source       string        `json:"source"`
    } `json:"dictionary"`
}

完整代码

项目三：SOCKS5 代理

  • 原理

uTools_1673779907033

  • author部分
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// +----+----------+----------+
// VER  NMETHODS  METHODS  
// +----+----------+----------+
//  1      1      1 to 255 
// +----+----------+----------+
// VER: 协议版本，socks5为0x05
// NMETHODS: 支持认证的方法数量
// METHODS: 对应NMETHODS，NMETHODS的值为多少，METHODS就有多少个字节。RFC预定义了一些值的含义，内容如下:
// X’00’ NO AUTHENTICATION REQUIRED
// X’02’ USERNAME/PASSWORD
  • Requests部分
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// +----+-----+-------+------+----------+----------+
// VER  CMD   RSV   ATYP  DST.ADDR  DST.PORT 
// +----+-----+-------+------+----------+----------+
//  1    1   X'00'   1    Variable     2     
// +----+-----+-------+------+----------+----------+
// VER 版本号，socks5的值为0x05
// CMD 0x01表示CONNECT请求
// RSV 保留字段，值为0x00
// ATYP 目标地址类型，DST.ADDR的数据对应这个字段的类型。
//   0x01表示IPv4地址，DST.ADDR为4个字节
//   0x03表示域名，DST.ADDR是一个可变长度的域名
// DST.ADDR 一个可变长度的值
// DST.PORT 目标端口，固定2个字节
  • Replies部分
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// +----+-----+-------+------+----------+----------+
// VER  REP   RSV   ATYP  BND.ADDR  BND.PORT 
// +----+-----+-------+------+----------+----------+
//  1    1   X'00'   1    Variable     2     
// +----+-----+-------+------+----------+----------+
// VER socks版本，这里为0x05
// REP Relay field,内容取值如下 X’00’ succeeded
// RSV 保留字段
// ATYPE 地址类型
// BND.ADDR 服务绑定的地址
// BND.PORT 服务绑定的端口DST.PORT

完整代码

四、课后作业：

修改第一个例子猜谜游戏里面的最终代码，使用fmt.Scanf来简化代码实现

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package main

import (
    "fmt"
    "math/rand"
    "time"
)

func main() {
    maxNum := 100
    rand.Seed(time.Now().UnixNano())
    secretNumber := rand.Intn(maxNum)
    // fmt.Println("The secret number is ", secretNumber)

    fmt.Println("Please input your guess")
    for {
        var guess int
        fmt.Scanf("%d ", &guess)
        fmt.Println("You guess is", guess)
        if guess > secretNumber {
            fmt.Println("Your guess is bigger than the secret number. Please try again")
        } else if guess < secretNumber {
            fmt.Println("Your guess is smaller than the secret number. Please try again")
        } else {
            fmt.Println("Correct, you Legend!")
            break
        }
    }
}

修改第二个例子命令行词典里面的最终代码，增加另一种翻译引擎的支持

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//go run .\go-by-example\simpledict\v4\main.go hello
package main

import (
    "bytes"
    "encoding/json"
    "fmt"
    "io/ioutil"
    "log"
    "net/http"
    "os"
)

type DictRequest struct {
    TransType string `json:"trans_type"`
    Source    string `json:"source"`
    UserID    string `json:"user_id"`
}

type DictResponse struct {
    Rc   int `json:"rc"`
    Wiki struct {
        KnownInLaguages int `json:"known_in_laguages"`
        Description     struct {
            Source string      `json:"source"`
            Target interface{} `json:"target"`
        } `json:"description"`
        ID   string `json:"id"`
        Item struct {
            Source string `json:"source"`
            Target string `json:"target"`
        } `json:"item"`
        ImageURL  string `json:"image_url"`
        IsSubject string `json:"is_subject"`
        Sitelink  string `json:"sitelink"`
    } `json:"wiki"`
    Dictionary struct {
        Prons struct {
            EnUs string `json:"en-us"`
            En   string `json:"en"`
        } `json:"prons"`
        Explanations []string      `json:"explanations"`
        Synonym      []string      `json:"synonym"`
        Antonym      []string      `json:"antonym"`
        WqxExample   [][]string    `json:"wqx_example"`
        Entry        string        `json:"entry"`
        Type         string        `json:"type"`
        Related      []interface{} `json:"related"`
        Source       string        `json:"source"`
    } `json:"dictionary"`
}

type DictRequest2 struct {
    Source         string   `json:"source"`
    Words          []string `json:"words"`
    SourceLanguage string   `json:"source_language"`
    TargetLanguage string   `json:"target_language"`
}

type DictResponse2 struct {
    Details []struct {
        Detail string `json:"detail"`
        Extra  string `json:"extra"`
    } `json:"details"`
    BaseResp struct {
        StatusCode    int    `json:"status_code"`
        StatusMessage string `json:"status_message"`
    } `json:"base_resp"`
}

type Detail struct {
    ErrorCode string `json:"errorCode"`
    RequestID string `json:"requestId"`
    Msg       string `json:"msg"`
    Result    []struct {
        Ec struct {
            ReturnPhrase []string `json:"returnPhrase"`
            Web          []struct {
                Phrase   string   `json:"phrase"`
                Meanings []string `json:"meanings"`
            } `json:"web"`
            Synonyms []struct {
                Pos   string   `json:"pos"`
                Words []string `json:"words"`
                Trans string   `json:"trans"`
            } `json:"synonyms"`
            Etymology struct {
                ZhCHS []struct {
                    Description string `json:"description"`
                    Detail      string `json:"detail"`
                    Source      string `json:"source"`
                } `json:"zh-CHS"`
            } `json:"etymology"`
            MTerminalDict string `json:"mTerminalDict"`
            Dict          string `json:"dict"`
            Basic         struct {
                UsPhonetic string   `json:"usPhonetic"`
                UsSpeech   string   `json:"usSpeech"`
                Phonetic   string   `json:"phonetic"`
                UkSpeech   string   `json:"ukSpeech"`
                ExamType   []string `json:"examType"`
                Explains   []struct {
                    Pos   string `json:"pos"`
                    Trans string `json:"trans"`
                } `json:"explains"`
                UkPhonetic  string `json:"ukPhonetic"`
                WordFormats []struct {
                    Name  string `json:"name"`
                    Value string `json:"value"`
                } `json:"wordFormats"`
            } `json:"basic"`
            Phrases []struct {
                Phrase   string   `json:"phrase"`
                Meanings []string `json:"meanings"`
            } `json:"phrases"`
            Lang           string `json:"lang"`
            SentenceSample []struct {
                Sentence     string `json:"sentence"`
                SentenceBold string `json:"sentenceBold"`
                Translation  string `json:"translation"`
            } `json:"sentenceSample"`
            IsWord  bool   `json:"isWord"`
            WebDict string `json:"webDict"`
        } `json:"ec"`
    } `json:"result"`
}

func query(word string) {
    client := &http.Client{}
    request := DictRequest{TransType: "en2zh", Source: word}
    buf, err := json.Marshal(request)
    if err != nil {
        log.Fatal(err)
    }
    var data = bytes.NewReader(buf)
    req, err := http.NewRequest("POST", "https://api.interpreter.caiyunai.com/v1/dict", data)
    if err != nil {
        log.Fatal(err)
    }
    req.Header.Set("Connection", "keep-alive")
    req.Header.Set("DNT", "1")
    req.Header.Set("os-version", "")
    req.Header.Set("sec-ch-ua-mobile", "?0")
    req.Header.Set("User-Agent", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.51 Safari/537.36")
    req.Header.Set("app-name", "xy")
    req.Header.Set("Content-Type", "application/json;charset=UTF-8")
    req.Header.Set("Accept", "application/json, text/plain, */*")
    req.Header.Set("device-id", "")
    req.Header.Set("os-type", "web")
    req.Header.Set("X-Authorization", "token:qgemv4jr1y38jyq6vhvi")
    req.Header.Set("Origin", "https://fanyi.caiyunapp.com")
    req.Header.Set("Sec-Fetch-Site", "cross-site")
    req.Header.Set("Sec-Fetch-Mode", "cors")
    req.Header.Set("Sec-Fetch-Dest", "empty")
    req.Header.Set("Referer", "https://fanyi.caiyunapp.com/")
    req.Header.Set("Accept-Language", "zh-CN,zh;q=0.9")
    req.Header.Set("Cookie", "_ym_uid=16456948721020430059; _ym_d=1645694872")
    resp, err := client.Do(req)
    if err != nil {
        log.Fatal(err)
    }
    defer resp.Body.Close()
    bodyText, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        log.Fatal(err)
    }
    if resp.StatusCode != 200 {
        log.Fatal("bad StatusCode:", resp.StatusCode, "body", string(bodyText))
    }
    var dictResponse DictResponse
    err = json.Unmarshal(bodyText, &dictResponse)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Println(word, "UK:", dictResponse.Dictionary.Prons.En, "US:", dictResponse.Dictionary.Prons.EnUs)
    for _, item := range dictResponse.Dictionary.Explanations {
        fmt.Println(item)
    }
    fmt.Println("By CaiYun")
}

func query2(word string) {
    client := &http.Client{}
    request := DictRequest2{Source: "youdao", Words: []string{word}, SourceLanguage: "en", TargetLanguage: "zh"}
    buf, err := json.Marshal(request)
    if err != nil {
        log.Fatal(err)
    }
    var data = bytes.NewReader(buf)
    req, err := http.NewRequest("POST", "https://translate.volcengine.com/web/dict/detail/v1/?msToken=&X-Bogus=DFSzswVLQDadxLyJSZW76tteJnyE&_signature=_02B4Z6wo00001ljRzmgAAIDCU11wL0iWDHZY0crAAPYG0kiMNFxedoitm5HLGUD0jZ5DcXIetnNY8ZGiALMbzgBDv1KOARzAc9zVX0hBbkTuGlfrQXxOs7iKnzDbkKrVsENB0LBFxbQpr7cx6d", data)
    if err != nil {
        log.Fatal(err)
    }
    req.Header.Set("authority", "translate.volcengine.com")
    req.Header.Set("accept", "application/json, text/plain, */*")
    req.Header.Set("accept-language", "zh-CN,zh;q=0.9,en;q=0.8,en-GB;q=0.7,en-US;q=0.6")
    req.Header.Set("content-type", "application/json")
    req.Header.Set("cookie", "x-jupiter-uuid=16737825730907524; i18next=zh-CN; s_v_web_id=verify_lcxaxfl8_82b7bTsx_spXo_4ojy_8eRx_vYijmz0YGEDK; ttcid=53e7468bfdd8463d9035633a3619cd1e27; tt_scid=kFfR0z7TRSKbDMjd5nuEbx.LtFvHzHFpDi1yQWzIA0zpggD470g9zU3L.lxerpe6c31c")
    req.Header.Set("origin", "https://translate.volcengine.com")
    req.Header.Set("referer", "https://translate.volcengine.com/mobile?category=&home_language=zh&source_language=detect&target_language=zh&text=hello")
    req.Header.Set("sec-ch-ua", `"Not?A_Brand";v="8", "Chromium";v="108", "Microsoft Edge";v="108"`)
    req.Header.Set("sec-ch-ua-mobile", "?0")
    req.Header.Set("sec-ch-ua-platform", `"Windows"`)
    req.Header.Set("sec-fetch-dest", "empty")
    req.Header.Set("sec-fetch-mode", "cors")
    req.Header.Set("sec-fetch-site", "same-origin")
    req.Header.Set("user-agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36 Edg/108.0.1462.76")
    resp, err := client.Do(req)
    if err != nil {
        log.Fatal(err)
    }
    defer resp.Body.Close()
    bodyText, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        log.Fatal(err)
    }
    var dictResponse2 DictResponse2
    var detail Detail
    err = json.Unmarshal(bodyText, &dictResponse2)
    if err != nil {
        log.Fatal(err)
    }
    err = json.Unmarshal([]byte(dictResponse2.Details[0].Detail), &detail)
    if err != nil {
        log.Fatal(err)
    }
    //fmt.Printf("%v", detail)
    fmt.Println(word, "UK:", detail.Result[0].Ec.Basic.Phonetic, "US:", detail.Result[0].Ec.Basic.UsPhonetic)
    for _, item := range detail.Result[0].Ec.Basic.Explains {
        fmt.Println(item.Pos, item.Trans)
    }
    fmt.Println("By HuoShan")
}

func main() {
    start := time.Now()
    if len(os.Args) != 2 {
        fmt.Fprintf(os.Stderr, `usage: simpleDict WORD
example: simpleDict hello
        `)
        os.Exit(1)
    }
    word := os.Args[1]
    query(word)
    fmt.Println()
    query2(word)
    elapsed := time.Since(start)
    fmt.Println(elapsed)
}

在上一步骤的基础上，修改代码实现并行请求两个翻译引擎来提高响应速度

修改main函数通过goroutine实现并发

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func main() {
    start := time.Now()
    if len(os.Args) < 2 {
        fmt.Fprintf(os.Stderr, `usage: simpleDict WORD
example: simpleDict hello
        `)
        os.Exit(1)
    }
    words := os.Args[1:]
    var word string
    for i, item := range words {
        if i != len(words)-1 {
            word += item + " "
        } else {
            word += item
        }
    }
    go func() {
        query(word)
    }()
    query2(word)
    time.Sleep(time.Second)
    elapsed := time.Since(start)
    fmt.Println(elapsed)
}

响应速度对比可得，并发后响应速度提升明显

uTools_1673798979137

tag:

    缺失模块。
    1、请确保node版本大于6.2
    2、在博客根目录（注意不是yilia根目录）执行以下命令：
    npm i hexo-generator-json-content --save

    3、在根目录_config.yml里添加配置： 

      jsonContent:
    meta: false
    pages: false
    posts:
      title: true
      date: true
      path: true
      text: false
      raw: false
      content: false
      slug: false
      updated: false
      comments: false
      link: false
      permalink: false
      excerpt: false
      categories: false
      tags: true

我叫KK<br><br> 杭州，程序员，IPC视频开发