Content-Length is not set when using MultiPartFormDataContent

Ktor Version - 1.1.1 Ktor Engine Used(client or server and name) - Client - okhttp JVM Version - 1.8.0 Operating System - Android Request: PUT content-type:  Multipart/form-data Ktor Client Engine: Okhttp & Android

As with the title, the Content-Length is not set when using MultiPartFormDataContent. We get transfer-encoding:  chunked instead. It is important to upload files to Django/WSGI powered backends as it is rather difficult about handling file uploads without Content-Length and other http clients such as Retrofit doesn’t have this problem because it added the content-length in  multipart/form-data uploads

 GlobalScope.launch(Dispatchers.Main) {
            try {
                client.submitForm {
                    url("http://192.168.1.47:8000/api/images/")
                    method = HttpMethod.Put
                    header(HttpHeaders.Authorization, "JWT $token")

                    body = MultiPartFormDataContent(
                        formData {
                            append(
                                "image",
                                data,
                                Headers.build {
                                    append(HttpHeaders.ContentType, "image/jpg")
                                    append(HttpHeaders.ContentDisposition, " filename=hello.jpg")
                                }
                            )
                        }
                    )
                }
            } catch (e: Exception){
                Log.d(this@MainActivity::class.java.simpleName, e.message)
            }
        }

[kmatias]

I am encountering this issue as well. The header of the multipart form request has transfer-encoding: chunked instead of Content-Length which the server requires.

Has anyone looked into this issue yet?

[charleston10]

I’ve this same problem in version 1.4.2, using android ktor in KMM How can I solve?

 override suspend fun postImage(filePath: String) {
        val inputFile = InputFile().getFile(filePath)
        val file = InputProvider { inputFile }

        httpClient
            .post<HttpResponse>(UrlProvider.posts) {
                headers { append("Accept", FORM_ACCEPT_MULTIPART) }
                body = MultiPartFormDataContent(formData {
                    append(
                        "file",
                        InputProvider(file.size) { buildPacket { writeFully(inputFile.readBytes()) } },
                        Headers.build {
                            append(HttpHeaders.ContentType, ContentType.Image.PNG.toString())
                            append(
                                HttpHeaders.ContentDisposition,
                                ContentDisposition.File.withParameter(
                                    ContentDisposition.Parameters.FileName,
                                    "test"
                                )
                            )
                        })
                })
            }
    }

Log

:method: POST
:path: /posts
:authority: 192.168.0.1:8080
:scheme: https
accept: multipart/form-data
accept-charset: UTF-8
content-type: multipart/form-data; boundary=-4944c64b-2fa78d1a-148ded0d-fbd9d7d669a8d-1709412d-2d6dc51e-185d27aa13
cache-control: public, max-age=5
accept-encoding: gzip

---4944c64b-2fa78d1a-148ded0d-fbd9d7d669a8d-1709412d-2d6dc51e-185d27aa13
Content-Disposition: form-data; name=file; file; filename=test
Content-Type: image/png


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