冒充客户端将MultiValueMap作为MultiPartFormData发送

Question

我正试图将下面的kotlin代码从RestTemplate转换为伪客户端。rest模板代码发送multiValueMap作为请求，其中包含内容类型的标题multipart/form-data，并使用JSON对象作为响应。

RestTemplate代码：

    var headers = HttpHeaders()
    headers.contentType = MediaType.MULTIPART_FORM_DATA
    headers.add("custom-header", "value")
    val body: MultiValueMap<String, Any> = LinkedMultiValueMap()
    body.add("field1", "value1")
    body.add("field2", "value2")
    val requestEntity = HttpEntity(body, headers)
    return restTemplate.postForEntity("https://enmf7tx8y37x.x.pipedream.net/", requestEntity, Object::class.java)

在这种情况下，请求发送如下：

标题：

Host: enmf7tx8y37x.x.pipedream.net
X-Amzn-Trace-Id: Root=1-6303ecb2-19a833a044ab3bf83f74f256
Content-Length: 342
Accept: application/xml, text/xml, application/json, application/*+xml, application/*+json
Content-Type: multipart/form-data;boundary=_MtEGFIF4XK_aOU8QsXstQuCliV1-llj
custom-header: value
X-B3-TraceId: a67561ec329f9a16
X-B3-SpanId: a6cc94e403bfe318
X-B3-ParentSpanId: a67561ec329f9a16
X-B3-Sampled: 1
User-Agent: Apache-HttpClient/4.5.13 (Java/17.0.3)
Accept-Encoding: gzip,deflate

正文：

 --_MtEGFIF4XK_aOU8QsXstQuCliV1-llj
    Content-Disposition: form-data; name="field1"
    Content-Type: text/plain;charset=UTF-8
    Content-Length: 6
    
    value1
    --_MtEGFIF4XK_aOU8QsXstQuCliV1-llj
    Content-Disposition: form-data; name="field2"
    Content-Type: text/plain;charset=UTF-8
    Content-Length: 6
    
    value2
    --_MtEGFIF4XK_aOU8QsXstQuCliV1-llj--

我也试图在假装的客户中这样做：

代码：

/*val headers = HttpHeaders()
    headers.contentType = MediaType.MULTIPART_FORM_DATA
    headers.add("custom-header", "value")*/
    val body: MultiValueMap<String, Any> = LinkedMultiValueMap()
    body.add("field1", "value1")
    body.add("field2", "value2")
    val result = testClient.test("value", body)

冒充客户：

@FeignClient(
  value = "testClient",
  url = "https://enmf7tx8y37x.x.pipedream.net/"
)
interface TestClient {
  @PostMapping(
    consumes = [MediaType.MULTIPART_FORM_DATA_VALUE],
    produces = [MediaType.APPLICATION_JSON_VALUE]
  )
  fun test(
    @RequestHeader(value = "custom-header") customHeader: String,
    @RequestPart("request") request: MultiValueMap<String, Any>
  ): ResponseEntity<Object>

}

标题很好，但在正文中没有显示值。

标题：

Host: enmf7tx8y37x.x.pipedream.net
X-Amzn-Trace-Id: Root=1-6303ef0f-78c869881a5b27d0707eab9e
Content-Length: 17
Accept: application/json
Authorization: Basic aHlwb2xhYjp0ZXN0c211cmY=
Content-Type: multipart/form-data; charset=UTF-8; boundary=182c75dd399
custom-header: value
X-B3-TraceId: 2989eb4f12e3d417
X-B3-SpanId: 23414bcdf365784c
X-B3-ParentSpanId: 2989eb4f12e3d417
X-B3-Sampled: 1
User-Agent: Java/17.0.3

正文：

--182c75dd399--

我不得不将consumes值添加为多部分/表单数据，而不是json，以便为Accept和Content-Type获得正确的头值。

如何使用虚拟客户端填充请求？如果@RequestPart是字符串，则该值将在正文中发送，但任何其他数据类型(如multiValueMap、byteArray等)都不能工作。

Answer 1

在假装客户端，您不能直接使用MultiValueMap。您必须对字节数组和其余的元数据字段使用MultipartFile数据类型，您需要在方法中将每个元数据字段作为单独的参数。然后，FeignClient将生成与使用RestTemplate时显示的请求相同的请求。

import org.springframework.cloud.openfeign.FeignClient
import org.springframework.web.bind.annotation.PostMapping
import org.springframework.http.MediaType
import org.springframework.http.ResponseEntity
import org.springframework.web.bind.annotation.RequestHeader
import org.springframework.web.bind.annotation.RequestPart
import org.springframework.web.multipart.MultipartFile

    @FeignClient(
      value = "testClient",
      url = "https://enmf7tx8y37x.x.pipedream.net/"
    )
    interface TestClient {
      @PostMapping(
        consumes = [MediaType.MULTIPART_FORM_DATA_VALUE],
        produces = [MediaType.APPLICATION_JSON_VALUE]
      )
      fun test(
        @RequestHeader(value = "custom-header") customHeader: String,
        @RequestPart(name = "file") file: MultipartFile,
        @RequestPart(name = "field1") field1: String
      ): ResponseEntity<Object>
    
    }

如何创建MultiPartFile的代码示例：

import org.springframework.mock.web.MockMultipartFile

//val multipartFile: MultipartFile = MockMultipartFile("filename", byteArray)
val multipartFile: MultipartFile = MockMultipartFile("filename", "filename", "content type like application/pdf", byteArray)