Go 语言的实战案例（含课后作业）｜青训营笔记Go 语言的实战案例，在线词典（彩云小译、百度翻译）如何用`Go`语言发

这是我参与「第五届青训营」伴学笔记创作活动的第 3 天
这是我参与「第五届青训营」的第 4 天

不确定作业是否正确，如有错误麻烦大佬指出，谢谢～
源码地址：https://github.com/wangkechun/go-by-example

在线词典

原理

调用第三方的API查询单词的翻译与音标

学习目标

如何用Go语言发送HTTP请求
解析json
如何使用代码生成提高开发效率

抓包

彩云小译：fanyi.caiyunapp.com/
打开开发工具：右键 -- 检查

输入good（任意一个单词） -- 点击翻译 -- 点击Network -- 点击最后一个dict请求（注意该请求中的Headers的Request Method:为Post，Payload、Preview如下）

代码生成

尝试在golang里面发送请求，可以发现请求是非常复杂的，用代码构造很麻烦，所以通过代码生成来生成请求
右键请求dict -- Copy -- Copy as cURL

代码生成网址：curlconverter.com/#go
将复制的内容粘贴在curl command内 -- 下方的编程语言选择Go

生成代码解读（strings.NewReader将字符串转换为流，减少内存占用）

在编译器中运行，返回json

json序列化 - 生成requeset body

调用json.Marshal()
修改代码 -- 查看代码差异

反序列化 - 解析requeset body

写一个结构体，结构体的字段与返回的json字段一一对应，但是一个一个写非常复杂且容易出错
代码生成：oktools.net/json2go
将Response中的json粘贴到网页左边

“转换-展开”：生成多个独立的结构体； “转换-嵌套”：生成一个结构体（代码比较紧凑）

修改代码 -- 查看代码差异

结果

打印结果（只打印要求的翻译、音标等）

完善代码（使得可以通过输入单词，得到相对应的结果）

课后作业

1. 修改猜谜游戏里面的最终代码，使用`fmt.Scanf`来简化代码实现

源代码的最终代码

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")
   reader := bufio.NewReader(os.Stdin)
   for {
      input, err := reader.ReadString('\n')
      if err != nil {
         fmt.Println("An error occured while reading input. Please try again", err)
         continue
      }
      input = strings.Trim(input, "\r\n")

      guess, err := strconv.Atoi(input)
      if err != nil {
         fmt.Println("Invalid input. Please enter an integer value")
         continue
      }
      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
      }
   }
}

使用fmt.Scanf来简化

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
      _, err := fmt.Scanf("%d\n", &guess)
      if err != nil {
         fmt.Println(err)
         continue
      }
      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
      }
   }
}

2. 修改命令行词典里面的最终代码，增加另一种翻译引擎的支持

源代码的最终代码

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"`
}

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)
   }
}

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

增加另一种翻译引擎的支持

只用百度翻译（在josn序列化部分发生了未知错误，笔者还不知道应该如何解决，所以没有用josn序列化；同时百度翻译的结果没有音标【好像是不同的借口】，所以没有输出）

package main

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

type BaiduDictRequest struct {
   kw string `json:"kw"`
}

type BaiduDictResponse struct {
   Errno int `json:"errno"`
   Data  []struct {
      K string `json:"k"`
      V string `json:"v"`
   } `json:"data"`
}

func querybaidu(word string) {
   client := &http.Client{}
   var data = strings.NewReader(`kw=` + word)

   //request := BaiduDictRequest{kw: "good"}
   //fmt.Println("request: ", request)
   //buf, err := json.Marshal(request)
   //fmt.Println("buf: ", buf)
   //if err != nil {
   // log.Fatal(err)
   //}
   //var data = bytes.NewReader(buf)
   //fmt.Println("data: ", data)

   req, err := http.NewRequest("POST", "https://fanyi.baidu.com/sug", data)
   if err != nil {
      log.Fatal(err)
   }
   req.Header.Set("Accept", "application/json, text/javascript, */*; q=0.01")
   req.Header.Set("Accept-Language", "zh-CN,zh;q=0.9")
   req.Header.Set("Connection", "keep-alive")
   req.Header.Set("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8")
   req.Header.Set("Cookie", "BAIDUID=ED09DB5C4C9EB2908CE85B5CDA42D3DC:FG=1; BAIDUID_BFESS=ED09DB5C4C9EB2908CE85B5CDA42D3DC:FG=1; BDUSS=lMZzVqNGt-RkFDLX5palJIWWt5eklCUU5SUlFWaUNuTE1wQ1RTSDI1T0IwOXRqSVFBQUFBJCQAAAAAAAAAAAEAAAB-3szUR2FsYXh5X0FJU3UAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAIFGtGOBRrRjWG; BDUSS_BFESS=lMZzVqNGt-RkFDLX5palJIWWt5eklCUU5SUlFWaUNuTE1wQ1RTSDI1T0IwOXRqSVFBQUFBJCQAAAAAAAAAAAEAAAB-3szUR2FsYXh5X0FJU3UAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAIFGtGOBRrRjWG; BIDUPSID=ED09DB5C4C9EB2908CE85B5CDA42D3DC; PSTM=1673792111; ZFY=bvelJRG1aS7aDNRufBYMn0RT9Oe1Lxr:BNrk24iQaOGA:C; BDRCVFR[feWj1Vr5u3D]=I67x6TjHwwYf0; PSINO=7; delPer=0; BA_HECTOR=8085808haha48k8g0k040hmb1hseuss1l; BDORZ=B490B5EBF6F3CD402E515D22BCDA1598; H_PS_PSSID=36543_38013_36920_37989_37795_37926_37873_38040_26350_37957_38008_37881; APPGUIDE_10_0_2=1; REALTIME_TRANS_SWITCH=1; FANYI_WORD_SWITCH=1; HISTORY_SWITCH=1; SOUND_SPD_SWITCH=1; SOUND_PREFER_SWITCH=1; Hm_lvt_64ecd82404c51e03dc91cb9e8c025574=1674025890; Hm_lpvt_64ecd82404c51e03dc91cb9e8c025574=1674026000; ab_sr=1.0.1_ODhiMTIxYTBjOTdiODZmMzhhMjQzZDI2ODg3YjMzNjdiODA1NjJjODk4N2VkYzVmNjA4YmJhZTM0NGFhYjY4YzU5MDhlNjYzMTA4M2E4ZmVhNGVmY2ZhNzg1YjdhZmRlOWVlZDdlNTA1ODNiODJlNzU2MTg4NWMwZTlhZTQ0Zjk3NGZjZTc3ODY4MGNkYThiNjUxYzNjODI5YWU3NmYwNGFiYzNhNmIxNDRjZTI3MzBjZWY4ZDg0ZTk1MmJjOWU3")
   req.Header.Set("Origin", "https://fanyi.baidu.com")
   req.Header.Set("Referer", "https://fanyi.baidu.com/")
   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 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36")
   req.Header.Set("X-Requested-With", "XMLHttpRequest")
   req.Header.Set("sec-ch-ua", `"Not_A Brand";v="99", "Google Chrome";v="109", "Chromium";v="109"`)
   req.Header.Set("sec-ch-ua-mobile", "?0")
   req.Header.Set("sec-ch-ua-platform", `"macOS"`)
   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)
   var dictResponse BaiduDictResponse
   err = json.Unmarshal(bodyText, &dictResponse)
   if err != nil {
      log.Fatal(err)
   }
   //fmt.Printf("%#v\n", dictResponse)
   for _, item := range dictResponse.Data {
      fmt.Println(item.K, ":", item.V)
   }
}

func main() {
   if len(os.Args) != 2 {
      fmt.Fprintf(os.Stderr, `usage: simpleDict WORD
example: simpleDict hello
      `)
      os.Exit(1)
   }
   fmt.Println(os.Args)
   word := os.Args[1]
   querybaidu(word)
}

两种翻译引擎

package main

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

// 百度
type BaiduDictRequest struct {
   kw string `json:"kw"`
}

type BaiduDictResponse struct {
   Errno int `json:"errno"`
   Data  []struct {
      K string `json:"k"`
      V string `json:"v"`
   } `json:"data"`
}

func querybaidu(word string) {
   client := &http.Client{}
   var data = strings.NewReader(`kw=` + word)

   //request := BaiduDictRequest{kw: "good"}
   //fmt.Println("request: ", request)
   //buf, err := json.Marshal(request)
   //fmt.Println("buf: ", buf)
   //if err != nil {
   // log.Fatal(err)
   //}
   //var data = bytes.NewReader(buf)
   //fmt.Println("data: ", data)

   req, err := http.NewRequest("POST", "https://fanyi.baidu.com/sug", data)
   if err != nil {
      log.Fatal(err)
   }
   req.Header.Set("Accept", "application/json, text/javascript, */*; q=0.01")
   req.Header.Set("Accept-Language", "zh-CN,zh;q=0.9")
   req.Header.Set("Connection", "keep-alive")
   req.Header.Set("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8")
   req.Header.Set("Cookie", "BAIDUID=ED09DB5C4C9EB2908CE85B5CDA42D3DC:FG=1; BAIDUID_BFESS=ED09DB5C4C9EB2908CE85B5CDA42D3DC:FG=1; BDUSS=lMZzVqNGt-RkFDLX5palJIWWt5eklCUU5SUlFWaUNuTE1wQ1RTSDI1T0IwOXRqSVFBQUFBJCQAAAAAAAAAAAEAAAB-3szUR2FsYXh5X0FJU3UAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAIFGtGOBRrRjWG; BDUSS_BFESS=lMZzVqNGt-RkFDLX5palJIWWt5eklCUU5SUlFWaUNuTE1wQ1RTSDI1T0IwOXRqSVFBQUFBJCQAAAAAAAAAAAEAAAB-3szUR2FsYXh5X0FJU3UAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAIFGtGOBRrRjWG; BIDUPSID=ED09DB5C4C9EB2908CE85B5CDA42D3DC; PSTM=1673792111; ZFY=bvelJRG1aS7aDNRufBYMn0RT9Oe1Lxr:BNrk24iQaOGA:C; BDRCVFR[feWj1Vr5u3D]=I67x6TjHwwYf0; PSINO=7; delPer=0; BA_HECTOR=8085808haha48k8g0k040hmb1hseuss1l; BDORZ=B490B5EBF6F3CD402E515D22BCDA1598; H_PS_PSSID=36543_38013_36920_37989_37795_37926_37873_38040_26350_37957_38008_37881; APPGUIDE_10_0_2=1; REALTIME_TRANS_SWITCH=1; FANYI_WORD_SWITCH=1; HISTORY_SWITCH=1; SOUND_SPD_SWITCH=1; SOUND_PREFER_SWITCH=1; Hm_lvt_64ecd82404c51e03dc91cb9e8c025574=1674025890; Hm_lpvt_64ecd82404c51e03dc91cb9e8c025574=1674026000; ab_sr=1.0.1_ODhiMTIxYTBjOTdiODZmMzhhMjQzZDI2ODg3YjMzNjdiODA1NjJjODk4N2VkYzVmNjA4YmJhZTM0NGFhYjY4YzU5MDhlNjYzMTA4M2E4ZmVhNGVmY2ZhNzg1YjdhZmRlOWVlZDdlNTA1ODNiODJlNzU2MTg4NWMwZTlhZTQ0Zjk3NGZjZTc3ODY4MGNkYThiNjUxYzNjODI5YWU3NmYwNGFiYzNhNmIxNDRjZTI3MzBjZWY4ZDg0ZTk1MmJjOWU3")
   req.Header.Set("Origin", "https://fanyi.baidu.com")
   req.Header.Set("Referer", "https://fanyi.baidu.com/")
   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 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36")
   req.Header.Set("X-Requested-With", "XMLHttpRequest")
   req.Header.Set("sec-ch-ua", `"Not_A Brand";v="99", "Google Chrome";v="109", "Chromium";v="109"`)
   req.Header.Set("sec-ch-ua-mobile", "?0")
   req.Header.Set("sec-ch-ua-platform", `"macOS"`)
   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)
   var dictResponse BaiduDictResponse
   err = json.Unmarshal(bodyText, &dictResponse)
   if err != nil {
      log.Fatal(err)
   }
   //fmt.Printf("%#v\n", dictResponse)
   fmt.Println("百度翻译结果：")
   for _, item := range dictResponse.Data {
      fmt.Println(item.K, ":", item.V)
   }
}

// 彩云
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"`
}

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("彩云翻译结果：")
   fmt.Println(word, "UK:", dictResponse.Dictionary.Prons.En, "US:", dictResponse.Dictionary.Prons.EnUs)
   for _, item := range dictResponse.Dictionary.Explanations {
      fmt.Println(item)
   }
}

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

3. 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

思路：开两个协程（goroutine）
目的：两个翻译引擎同时翻译，那个快返回那个的结果（所以结果只会有一个）
只要将上面代码的main函数改成以下代码即可

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

   ctx, cancel := context.WithCancel(context.Background())
   defer cancel()

   go func() {
      querybaidu(word)
      cancel()
   }()
   go func() {
      query(word)
      cancel()
   }()

   <-ctx.Done()
}

总结反思

作为一个go初学者，感觉青训营的课程理解起来不算难，但是一到自己动手实践时感觉还是有点点难度，主要原因就是不熟练吧～想要掌握一门语言还是得多动手实践呀！

Go 语言的实战案例（含课后作业）｜青训营笔记