Okhttp: http/2 works except when using okhttp-urlconnection

[hrj]

Here's a kotlin script that reproduces the problem:

import okhttp3.*

val client = OkHttpClient.Builder()
  .protocols(listOf(Protocol.HTTP_1_1, Protocol.HTTP_2))
  .build()

fun directConnect() {
    val url = HttpUrl.parse("https://http2.akamai.com/")
    val request = Request.Builder()
        .url(url)
        .build()

    val response = client.newCall(request).execute()
    println("Headers from direct connection")
    response.headers().names().forEach { if (it.contains("proto")) {println(it +  response.headers().values(it))} }
}

fun urlConnect() {
    val url = java.net.URL("https://http2.akamai.com/")
    val urlFactory = okhttp3.OkUrlFactory(client)
    java.net.URL.setURLStreamHandlerFactory(urlFactory);
    val connection = url.openConnection()
    val headers = connection.getHeaderFields()
    println("Headers from url connection")
    headers.keys.forEach{ if (it != null && it.contains("proto")) {println(it +  headers.get(it))} }
}

println(System.getProperty("java.home"))
directConnect()
println("--------------")
urlConnect()

Command to run the script:

kotlinc -cp okhttp-3.12.1.jar:okio-1.17.2.jar:okhttp-urlconnection-3.12.1.jar -script http2.kts

The output I see on Java 10 is:

Headers from direct connection
myproto[h2]
protocol_negotiation[h2]
--------------
Headers from url connection
myproto[]
protocol_negotiation[h1]

That is, directly using OkHTTP client results in http/2 neogitation, but using url-connection results in http1.x.

---

By quickly scanning the code, I was unable to determine if this is a fundamental limitation or just a bug.

[amirlivneh]

Try calling setURLStreamHandlerFactory() before creating the URL in urlConnect().

[hrj]

Sweet, that worked!

Thanks @amirlivneh