# Can I use an InputStream as a body in Ktor HTTP client? **URL:** \ **Category:** Libraries\ **Created:** [January 6, 2022, 4:06pm UTC](https://discuss.kotlinlang.org/t/can-i-use-an-inputstream-as-a-body-in-ktor-http-client/23855 "2022-01-06T16:06:14Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![ioannis](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.kotlinlang.org/ioannis/32/9075_2.png) [@ioannis](https://discuss.kotlinlang.org/u/ioannis)\ **Post date:** [January 6, 2022, 4:06pm UTC](https://discuss.kotlinlang.org/t/can-i-use-an-inputstream-as-a-body-in-ktor-http-client/23855/1 "2022-01-06T16:06:14Z")
Hello folks! I am stumped by something I have not been able to figure out myself despite considerable experimentation and googling. In a nutshell, what I want to do is feed an InputStream as the body of a PUT request. I thought I could maybe use a ChannelWriterContent and provide a block that writes to the ByteWriteChannel but that was a bust. I can obviously readBytes() from the InputStream, but the stream can be arbitrarily large and I do not want to shove everything in memory. Does anyone know of a way to achieve this? Thanks! ---
**Author:** ![ioannis](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.kotlinlang.org/ioannis/32/9075_2.png) [@ioannis](https://discuss.kotlinlang.org/u/ioannis)\ **Post date:** [January 6, 2022, 5:59pm UTC](https://discuss.kotlinlang.org/t/can-i-use-an-inputstream-as-a-body-in-ktor-http-client/23855/2 "2022-01-06T17:59:13Z")
By the way I have managed to get this to work, but it feels very wrong ```auto private suspend fun sendFile(data: InputStream, url: String) { client.use { it.put(url) { body = object : OutgoingContent.ReadChannelContent() { override val contentType = OctetStream override val contentLength = data.available().toLong() override fun readFrom(): ByteReadChannel { return data.toByteReadChannel() } } } } } ``` is there a better way? ---
**Author:** ![broot](https://avatars.discourse-cdn.com/v4/letter/b/a88e57/32.png) [@broot](https://discuss.kotlinlang.org/u/broot)\ **Post date:** [January 6, 2022, 6:08pm UTC](https://discuss.kotlinlang.org/t/can-i-use-an-inputstream-as-a-body-in-ktor-http-client/23855/3 "2022-01-06T18:08:52Z")
I don’t think this is a bad solution. It does exactly what it should - it reads body from your input stream. I would probably verify that `InputStream` is automatically closed, but I guess it is. Anyway, if for some reason you prefer to use `ChannelWriterContent` then you just need to write while reading - instead of reading the whole stream with `readBytes()`. You can do it manually, by creating a buffer, then reading and writing. You can also use existing `copyTo()` extension: ```kotlin override suspend fun writeTo(channel: ByteWriteChannel) { inputStream.copyTo(channel) } ``` ---
**Author:** ![ioannis](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.kotlinlang.org/ioannis/32/9075_2.png) [@ioannis](https://discuss.kotlinlang.org/u/ioannis)\ **Post date:** [January 6, 2022, 6:32pm UTC](https://discuss.kotlinlang.org/t/can-i-use-an-inputstream-as-a-body-in-ktor-http-client/23855/4 "2022-01-06T18:32:21Z")
Thank you very much for your response! I tried your suggestion but it didn’t work, it looks like nothing is being received at the other end ```auto it.put(url) { body = object : OutgoingContent.WriteChannelContent() { override val contentType = OctetStream override suspend fun writeTo(channel: ByteWriteChannel) { data.copyTo(channel) } } } ``` Is this what you meant? I would have expected Ktor to do chunked transfer in the absence of a defined length, but it doesn’t look like it is happening ☹ ---
**Author:** ![broot](https://avatars.discourse-cdn.com/v4/letter/b/a88e57/32.png) [@broot](https://discuss.kotlinlang.org/u/broot)\ **Post date:** [January 6, 2022, 6:51pm UTC](https://discuss.kotlinlang.org/t/can-i-use-an-inputstream-as-a-body-in-ktor-http-client/23855/5 "2022-01-06T18:51:16Z")
Yes, this is what I meant. I’m not any expert here, but I think it should work and actually it worked when I tested it. And yes, it uses chunked transfer: ```auto User-Agent: Ktor client Content-Type: application/octet-stream Transfer-Encoding: chunked d Hello World! 0 ``` ---
**Author:** ![ioannis](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.kotlinlang.org/ioannis/32/9075_2.png) [@ioannis](https://discuss.kotlinlang.org/u/ioannis)\ **Post date:** [January 6, 2022, 7:16pm UTC](https://discuss.kotlinlang.org/t/can-i-use-an-inputstream-as-a-body-in-ktor-http-client/23855/6 "2022-01-06T19:16:47Z")
Huh how bizarre, S3 tells me to get lost ```auto 2022-01-06T19:11:44.330142+00:00 [25644]: [DefaultDispatcher-worker-1] [INFO] io.ktor.client.HttpClient: METHOD: HttpMethod(value=PUT) 2022-01-06T19:11:44.331716+00:00 [25644]: [DefaultDispatcher-worker-1] [INFO] io.ktor.client.HttpClient: COMMON HEADERS 2022-01-06T19:11:44.333060+00:00 [25644]: [DefaultDispatcher-worker-1] [INFO] io.ktor.client.HttpClient: -> Accept: */* 2022-01-06T19:11:44.334316+00:00 [25644]: [DefaultDispatcher-worker-1] [INFO] io.ktor.client.HttpClient: -> Accept-Charset: UTF-8 2022-01-06T19:11:44.335466+00:00 [25644]: [DefaultDispatcher-worker-1] [INFO] io.ktor.client.HttpClient: CONTENT HEADERS 2022-01-06T19:11:44.336674+00:00 [25644]: [DefaultDispatcher-worker-1] [INFO] io.ktor.client.HttpClient: -> Content-Type: application/octet-stream 2022-01-06T19:11:44.960727+00:00 [25644]: [DefaultDispatcher-worker-1] [INFO] io.ktor.client.HttpClient: RESPONSE: 501 Not Implemented ``` S3 verbose error ```auto NotImplementedA header you provided implies functionality that is not implemented
Transfer-Encoding
xxxxxxxxxx" ```