有没有一种方法可以在Golang中格式化这个JSON？

huangapple
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英文:

Is there a way to format this json in golang?

问题

我刚开始学习Go语言，我正在尝试构建一个简单的Rest API Web服务器。

这是我想要发送给Web服务器的每个请求的响应结构体：

  1. package main
  3. type HttpResp struct{
  4.     Status      int         `json:"status"`
  5.     Description string      `json:"description"`
  6.     Body        interface{} `json:"body"`
  7. }

这是我的articles.go文件，其中包含从数据库中获取所有文章的函数：

  1. package main
  3. import (
  4.     "encoding/json"
  5.     "net/http"
  6.     "log"
  7. )
  9. type Article struct{
  10.     Id          string `json:"id"`
  11.     Title       string `json:"title"`
  12.     Body        string `json:"body"`
  13.     Description string `json:"description"`
  14. }
  16. func AllArticles(w http.ResponseWriter, r *http.Request){
  17.     log.Print("/articles - GET")
  18.     db := connect()
  19.     defer db.Close()
  21.     var articles []Article
  22.     results, err := db.Query("SELECT * FROM Articles")
  23.     
  24.     if err != nil{
  25.         log.Print(err)
  26.         return
  27.     }
  29.     for results.Next(){
  30.         var article Article
  31.         err = results.Scan(&article.Title, &article.Description, &article.Body, &article.Id)
  33.         if err != nil{
  34.             serr, _ := json.Marshal(err)
  35.             json.NewEncoder(w).Encode(HttpResp{Status: 500, Description: "Failed to retrieve all articles", Body: string(serr)})
  36.         }
  38.         articles = append(articles, article)
  39.     }   
  40.     sarr, _ := json.Marshal(articles)
  42.     w.Header().Set("Content-Type", "application/json")
  43.     json.NewEncoder(w).Encode(HttpResp{Status: 200, Body: json.RawMessage(sarr)})
  44. }

我在这里遇到的问题是响应的格式如下：

  1. {"status":200,"description":"","body":"[{\"id\":\"1\",\"title\":\"First\",\"body\":\"This is a test body\",\"description\":\"This is a test\"}]"}

我希望body只是一个JSON而不是一个字符串。我该如何实现这一点？

英文:

I'm just starting to learn GoLang today, I'm trying to build a simple Rest API Web server.

Here's the response Struct I want to send for each request to the web server :

  1. package main
  3. type HttpResp struct{
  4. 	Status		int			`json:"status"`
  5. 	Description	string		`json:"description"`
  6. 	Body		string		`json:"body"`
  7. }

And here's my articles.go file who have the function who gets all the articles in the database :

  1. package main
  3. import (
  4. 	"encoding/json"
  5. 	"net/http"
  6. 	"log"
  7. )
  9. type Article struct{
  10. 	Id			string	`json:"id"`
  11. 	Title		string	`json:"title"`
  12. 	Body		string	`json:"body"`
  13. 	Description	string	`json:"description"`
  14. }
  16. func AllArticles(w http.ResponseWriter, r *http.Request){
  17. 	log.Print("/articles - GET")
  18. 	db := connect()
  19. 	defer db.Close()
  21. 	var articles []Article
  22. 	results, err := db.Query("SELECT * FROM Articles")
  23. 	
  24. 	if err != nil{
  25. 		log.Print(err)
  26. 		return
  27. 	}
  29. 	for results.Next(){
  30. 		var article Article
  31. 		err = results.Scan(&article.Title, &article.Description, &article.Body, &article.Id)
  33. 		if err != nil{
  34. 			serr, _ := json.Marshal(err)
  35. 			json.NewEncoder(w).Encode(HttpResp{Status: 500, Description: "Failed to retrieve all articles", Body: string(serr)})
  36. 		}
  38. 		articles = append(articles, article)
  39. 	}	
  40. 	sarr, _ := json.Marshal(articles)
  42. 	w.Header().Set("Content-Type", "application/json")
  43. 	json.NewEncoder(w).Encode(HttpResp{Status: 200, Body: string(sarr)})
  44. }

The issue I'm facing here is that the response is like this :

> {"status":200,"description":"","body":"[{"id":"1","title":"First","body":"This
> is a test body","description":"This is a test"}]"}

I'd like the body to be just JSON and not a string. How can I acheive that ?

答案1

得分: 2

没有必要将body与HttpResp分开进行编排。相反，将Body字段的类型更改为interface{}，然后将该字段设置为具体类型的任何值，而不是JSON字符串，例如[]Article，然后一次编排响应。

  1. type HttpResp struct{
  2.     Status      int         `json:"status"`
  3.     Description string      `json:"description"`
  4.     Body        interface{} `json:"body"`
  5. }
  7. And the rest...
  9. package main
  11. import (
  12.     "encoding/json"
  13.     "net/http"
  14.     "log"
  15. )
  17. type Article struct{
  18.     Id          string  `json:"id"`
  19.     Title       string  `json:"title"`
  20.     Body        string  `json:"body"`
  21.     Description string  `json:"description"`
  22. }
  24. func AllArticles(w http.ResponseWriter, r *http.Request){
  25.     log.Print("/articles - GET")
  26.     db := connect()
  27.     defer db.Close()
  29.     var articles []Article
  30.     results, err := db.Query("SELECT * FROM Articles")
  32.     if err != nil{
  33.         log.Print(err)
  34.         return
  35.     }
  37.     for results.Next(){
  38.         var article Article
  39.         err = results.Scan(&article.Title, &article.Description, &article.Body, &article.Id)
  41.         if err != nil{
  42.             serr, _ := json.Marshal(err)
  43.             json.NewEncoder(w).Encode(HttpResp{Status: 500, Description: "Failed to retrieve all articles", Body: string(serr)})
  44.         }
  46.         articles = append(articles, article)
  47.     }
  49.     w.Header().Set("Content-Type", "application/json")
  50.     json.NewEncoder(w).Encode(HttpResp{Status: 200, Body: articles})
  51. }
英文:

No point in marshalling the body separately from the HttpResp. Instead change the Body field's type to interface{} and then set the field to any value of a concrete type as opposed to a json string, e.g. []Article and then marshal the resp once.

  1. type HttpResp struct{
  2. Status      int         `json:"status"`
  3. Description string      `json:"description"`
  4. Body        interface{} `json:"body"`
  5. }

And the rest...

  1. package main
  2. import (
  3. "encoding/json"
  4. "net/http"
  5. "log"
  6. )
  7. type Article struct{
  8. Id          string  `json:"id"`
  9. Title       string  `json:"title"`
  10. Body        string  `json:"body"`
  11. Description string  `json:"description"`
  12. }
  13. func AllArticles(w http.ResponseWriter, r *http.Request){
  14. log.Print("/articles - GET")
  15. db := connect()
  16. defer db.Close()
  17. var articles []Article
  18. results, err := db.Query("SELECT * FROM Articles")
  19. if err != nil{
  20. log.Print(err)
  21. return
  22. }
  23. for results.Next(){
  24. var article Article
  25. err = results.Scan(&article.Title, &article.Description, &article.Body, &article.Id)
  26. if err != nil{
  27. serr, _ := json.Marshal(err)
  28. json.NewEncoder(w).Encode(HttpResp{Status: 500, Description: "Failed to retrieve all articles", Body: string(serr)})
  29. }
  30. articles = append(articles, article)
  31. }
  32. w.Header().Set("Content-Type", "application/json")
  33. json.NewEncoder(w).Encode(HttpResp{Status: 200, Body: articles})
  34. }

huangapple
  • 本文由 发表于 2017年8月26日 05:08:27
  • 转载请务必保留本文链接：https://go.coder-hub.com/45889437.html
  • go
  • json
  • rest
  • webserver
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