I'm building an app with Spring Boot 2.1.6.RELEASE & Webflux
We have an endpoint that we can upload files using multipart and are using WebClient for our uploads.
Our upload client code looks like this
@Component
class UploadClient(
private val client: WebClient,
) {
suspend fun upload(filePath: String) =
client.post()
.uri("/upload")
.contentType(MULTIPART_FORM_DATA)
.body(BodyInserters.fromMultipartData(generateMultipartBody(filePath)))
.retrieve()
.bodyToMono(UploadResult::class.java)
.awaitFirst()
private fun generateMultipartBody(filePath: String): MultiValueMap<String, HttpEntity<*>> {
val builder = MultipartBodyBuilder()
builder.part("file", FileSystemResource(filePath))
return builder.build()
}
}
However when we upload a large file, (1.6gb) we are seeing that this entire file is loaded into direct memory:
As the file is uploaded, the memory is released, then when the next file is uploaded you can see the spike in memory again.
For contrast I tried replacing WebClient with https://github.com/AsyncHttpClient/async-http-client and the memory usage is much lower, ~60mb per upload
I don't really want to pull in another http client dependency when the WebFlux client is fine for all of our other uses.
