ruby-on-rails - 带有 json 和文件数据的法拉第多部分请求

Question

尝试使用 Faraday gem POST 多部分数据(文件和 json)时，远程服务器无法识别 json 数据参数并且由于验证错误而失败，因为它是必需参数。

connection = Faraday.new(url: "#{uri.scheme}://#{uri.host}:#{uri.port}") do |faraday|
              faraday.request :multipart
              faraday.request :url_encoded

              faraday.adapter :net_http
            end

request_data = { file: Faraday::UploadIO.new('somefile.png', 'image/png'), jsonBody: JSON.dump({ id: 'foo', name: 'bar' }) }

response = connection.post(uri.request_uri) do |request|
  request = Ff::Api::RequestHeaders.set(request, self.api_options)
  request.headers['content-type'] = 'multipart/form-data; boundary=-----------RubyMultipartPost'
  request.body = request_data
end

工作 CURL 请求:

curl -v -H 'Authorization: bearer 7d70fb31-0eb9-4846-9ea8-933dfb69d8f1' \
-H 'Accept: application/xml,application/xhtml+xml,application/json,text/html,text/plain' \
-H 'Content-Type: multipart/form-data' \
-F 'jsonBody={"id":"foo","name":"bar"};type=application/json' \
'http://localhost:8080/localproject/rest-resource/items'

curl 日志:

*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to localhost (127.0.0.1) port 8080 (#0)
> POST /localproject/rest-resource/items HTTP/1.1
> Host: localhost:8080
> Authorization: bearer 7d70fb31-0eb9-4846-9ea8-933dfb69d8f1
> USER_IP_ADDR: 127.0.0.1
> Accept: application/xml,application/xhtml+xml,application/json,text/html,text/plain
> Content-Length: 555
> Expect: 100-continue
> Content-Type: multipart/form-data; boundary=------------------------0c5f3acb5a4731ff
> 
< HTTP/1.1 100 Continue
< HTTP/1.1 200 OK
< Server: Apache-Coyote/1.1
< Cache-Control: no-cache, no-store, max-age=0, must-revalidate
< Pragma: no-cache
< Expires: 0
< X-XSS-Protection: 1; mode=block
< X-Frame-Options: DENY
< X-Content-Type-Options: nosniff
< Content-Type: application/xml
< Transfer-Encoding: chunked
< Date: Thu, 08 Feb 2018 10:50:06 GMT
< 
* Connection #0 to host localhost left intact
<?xml version="1.0" encoding="UTF-8" standalone="yes"?><updateResponse><id>5ce0b335-4638-474c-8c4a-9adb6c54b057</id><success>true</success></updateResponse>% 

请求正文的附加前缀“type=application/json”似乎与 CURL 有所不同。没有找到任何方法可以对法拉第做同样的事情。

法拉第版 : 0.12.2 & 0.14.0

ruby 版 : 2.3.3

rails : 5.2

任何帮助将不胜感激。

Answer 1

发现 Faraday 不支持 mix multipart request (file upload with json/xml data)。这是因为混合文件和 json 数据不是 Restful 方法，应该完全避免。更多讨论正在这里进行 https://github.com/lostisland/faraday/issues/769

我通过修补 Faraday::Mulitipart 暂时解决了这个问题允许混合 JSON 数据的类，

class Faraday::Request::Multipart
  def create_multipart(env, params)
    boundary = env.request.boundary
    parts = process_params(params) do |key, value|
      if (JSON.parse(value) rescue false)
        Faraday::Parts::Part.new(boundary, key, value, 'Content-Type' => 'application/json')
      else
        Faraday::Parts::Part.new(boundary, key, value)
      end
    end
    parts << Faraday::Parts::EpiloguePart.new(boundary)

    body = Faraday::CompositeReadIO.new(parts)
    env.request_headers[Faraday::Env::ContentLength] = body.length.to_s
    return body
  end
end

但从长远来看，应该更改服务器实现以避免混合多部分请求。