apollo-kotlin: gzip server responses break JS client

Fixed with 3.7.4: https://github.com/apollographql/apollo-kotlin/releases/tag/v3.7.4

Thanks for the details and sorry for the delay, this stuff is hairy. I was able to reproduce with this:

    val client = io.ktor.client.HttpClient(Js)

    val response = client.get("https://raw.githubusercontent.com/apollographql/apollo-kotlin/main/renovate.json")
    
    // throws IllegalStateException: Expected 112, actual 113
    println(response.body<ByteArray>())

    // works fine
    // println(response.body<String>())

It looks like a Ktor bug in the ByteArray conversion. I’ll dig more and update this issue. Thanks!

After I’ve checked the source code and documentation of ktor, I was wondering if it’s necessary to install the ContentEncoding plugin of Ktor when you instantiate the KtorHttpEngine? I’ve also tried to fiddle around with a tiny example:

import io.ktor.client.*
import io.ktor.client.engine.cio.*
import io.ktor.client.plugins.compression.*
import io.ktor.client.request.*
import io.ktor.client.statement.*
import io.ktor.http.*
import kotlinx.coroutines.runBlocking

val client = HttpClient(CIO) {
    install(ContentEncoding) {
        gzip()
    }
}
runBlocking {
    val response = client.get("http://localhost:8082/health") {
        contentType(ContentType.Application.Json)
        // header("Accept-Encoding", "gzip")
    }
    println(response.headers)
    println(response.bodyAsText())
}

If I disable the plugin, then the request won’t contain an Accept-Encoding header, unless I explicitly set it a few lines below, but when I do so, the request fails (correctly), because the client doesn’t really expect a gzipped response. The suspicious part is that there is an Accept-Encoding header in the outgoing requests in our case in the browser, which should not be possible according to their docs, and also to the example above.

I’ll try one last thing which is trying to run the test in the browser (and not node.js). Maybe there’s something different there but appart from that, I’m not sure…

I also checked in the browser with the built-in debugger, and that contentEncoding variable has a null value runtime 😕