@Multipart is not possible to send a charset together with multipart/form-data

[thiagoyf]

What kind of issue is this?

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I tried to use retrofit to send requests to a server that has some blocking rules. When I was trying to send a request to my backend with Multipart, it didn't reach my backend. I spent some time investigating why it happened and I found that my requisition lacked charset sent with multipart/form-data.

The code that I had to written on OkHttp:

val mediaType = "multipart/form-data; charset=utf-8".toMediaType()
val headers = Headers.headersOf("Content-Disposition", "form-data; name=\"myjson\"")

val multipartPartBody = """{"body":"hello"}""".toRequestBody()
val multipartBody = MultipartBody.Builder()
                    .setType(mediaType)
                    .addPart(headers, multipartPartBody)
                    .build()

val request = Request.Builder()
                    .url(myUrl)
                    .put(multipartBody)
                    .build()

val response = client.newCall(request).execute()

I couldn't send this way to the backend with Retrofit

I just wanted a way to send a request with this charset with Retrofit

[ssiegler]

It seems like this would also allow to send other multipart types like multipart/related or multipart/mixed. Or is there already some better way to do so using retrofit?

[cuihaifengchina]

后台服务器 undertow 不支持这种请求，换成tomact就好了，排查下后台

[thiagoyf]

The way that retrofit builds a multipart/form-data it doesn't allow us to build a request with charset to utf-8 like multipart/form-data; charset=utf-8 which could lead to syntax errors. One example is like

https://www.ibm.com/mysupport/s/question/0D50z000062krW2CAI/encoding-problems-when-using-multipartformdata?language=en_US

[tomridder]

The way that retrofit builds a multipart/form-data it doesn't allow us to build a request with charset to utf-8 like multipart/form-data; charset=utf-8 which could lead to syntax errors. One example is like

https://www.ibm.com/mysupport/s/question/0D50z000062krW2CAI/encoding-problems-when-using-multipartformdata?language=en_US

do u mean u want to let retrofit do the part of
val mediaType = "multipart/form-data; charset=utf-8".toMediaType()?