英文:
How to write a GET endpoint in Gin that lets the user download a file + metadata in json format?
问题
我已经创建了一个允许用户上传以JSON格式存储文件和元数据的端点，但是我在创建一个GET端点时遇到了一些问题，该端点允许用户在一次调用中下载文件和元数据。
我编写了下面的代码，它返回了JSON元数据+文件，但是JSON被添加到文件的开头，而不是作为一个单独的对象：
jsonData, err := json.Marshal(metadata)
// 设置响应头
c.Header("Content-Disposition", "attachment; filename=file.md")
c.Header("Content-Type", "application/octet-stream")
// 将文件内容和JSON数据写入响应体
c.Writer.Write(jsonData)
c.Writer.Write(file)
我该如何解决这个问题？
英文:
I have created an endpoint that allows users to upload a file + metadata in json format and I store them but I have some problems creating a GET endpoint that allows a user to download the file and metadata in json format in one call.
I wrote below code that returns the json metadata + file BUT the json is added at the beginning of the file and not as a separate object:
jsonData, err := json.Marshal(metadata)
// Set the response headers
c.Header("Content-Disposition", "attachment; filename=file.md")
c.Header("Content-Type", "application/octet-stream")
// Write the file contents and JSON data to the response body
c.Writer.Write(jsonData)
c.Writer.Write(file)
How can I solve this issue?
答案1
得分: 0
使用https://stackoverflow.com/users/5027489/whitesword的提示，我重写了代码以使用multipart/form-data，并解决了问题：
// 设置响应头
c.Header("Content-Disposition", "attachment; filename=file.md")
c.Header("Content-Type", "multipart/form-data")
// 创建一个多部分响应写入器
writer := multipart.NewWriter(c.Writer)
defer writer.Close()
// 将文件添加到响应中
fileWriter, err := writer.CreateFormFile("file", "file.md")
if err != nil {
c.JSON(http.StatusInternalServerError, gin.H{"error": "无法创建表单文件"})
return
}
fileWriter.Write(file)
// 将JSON数据添加到响应中
jsonWriter, err := writer.CreateFormField("metadata")
if err != nil {
c.JSON(http.StatusInternalServerError, gin.H{"error": "无法创建表单字段"})
return
}
jsonWriter.Write(jsonData)
// 完成多部分响应
c.Writer.Header().Set("Content-Type", writer.FormDataContentType())
// 返回响应
c.Writer.WriteHeader(http.StatusOK)
英文:
Using the https://stackoverflow.com/users/5027489/whitesword hint I rewrite my code to use multipart/form-data and that solved the problem:
// Set the response headers
c.Header("Content-Disposition", "attachment; filename=file.md")
c.Header("Content-Type", "multipart/form-data")
// Create a multipart response writer
writer := multipart.NewWriter(c.Writer)
defer writer.Close()
// Add the file to the response
fileWriter, err := writer.CreateFormFile("file", "file.md")
if err != nil {
c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to create form file"})
return
}
fileWriter.Write(file)
// Add the JSON data to the response
jsonWriter, err := writer.CreateFormField("metadata")
if err != nil {
c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to create form field"})
return
}
jsonWriter.Write(jsonData)
// Complete the multipart response
c.Writer.Header().Set("Content-Type", writer.FormDataContentType())
// Return the response
c.Writer.WriteHeader(http.StatusOK)
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论