Retry test

/*
 * Copyright (C) 2020 Square, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.compare

import java.io.IOException
import java.time.Duration
import java.util.concurrent.CountDownLatch
import java.util.concurrent.Executors
import java.util.concurrent.LinkedBlockingQueue
import java.util.concurrent.ThreadPoolExecutor
import java.util.concurrent.ThreadPoolExecutor.CallerRunsPolicy
import java.util.concurrent.TimeUnit
import mockwebserver3.MockWebServer
import okhttp3.Call
import okhttp3.Callback
import okhttp3.ConnectionPool
import okhttp3.Dispatcher
import okhttp3.Interceptor
import okhttp3.OkHttpClient
import okhttp3.Protocol
import okhttp3.Request
import okhttp3.Response
import org.junit.jupiter.api.Test

/**
 * OkHttp.
 *
 * https://square.github.io/okhttp/
 */
class OkHttpClientTest {
  @Test fun get(server: MockWebServer) {
    val connectionPool = ConnectionPool(8, 5, TimeUnit.MINUTES)
    val dispatcher = Dispatcher(
      ThreadPoolExecutor(
        8,
        8,
        1, TimeUnit.MINUTES,
        LinkedBlockingQueue(16),
        Executors.defaultThreadFactory(),
        CallerRunsPolicy()
      )
    )
    dispatcher.maxRequestsPerHost = 8
    dispatcher.maxRequests = 8

    val builder = OkHttpClient().newBuilder()
      .retryOnConnectionFailure(false)
      .callTimeout(Duration.ofSeconds(10))
      .readTimeout(Duration.ofSeconds(3))
      .writeTimeout(Duration.ofSeconds(3))
      .dispatcher(dispatcher)
      .connectionPool(connectionPool)
      .addInterceptor(OkHttpRetryInterceptor(3))

    val client = builder
      .protocols(listOf(Protocol.HTTP_1_1))
      .build()

    val request = Request.Builder()
        .url("https://nghttp2.org/httpbin/status/500")
        .build()

    val requests = 10
    val latch = CountDownLatch(requests)

    val responseCallback = object : Callback {
      override fun onFailure(call: Call, e: okio.IOException) {
        println(e)
        latch.countDown()
      }

      override fun onResponse(call: Call, response: Response) {
        println(response.code)
        // response.close()
        latch.countDown()
      }
    }

    repeat(10) {
      client.newCall(request).enqueue(responseCallback)
    }

    latch.await()
  }
}

class OkHttpRetryInterceptor(var maxRetryTimes: Int) : Interceptor {
  val retryInterval = 200L

  @Throws(IOException::class) override fun intercept(chain: Interceptor.Chain): Response {
    val request = chain.request()
    var response = chain.proceed(request)
    var retryCount = 1
    while (!response.isSuccessful && retryCount <= maxRetryTimes) {
      val wait = retryInterval * retryCount
      println(
        "okhttp retry: retry count = $retryCount, wait = $wait ms, response = $response"
      )
      response.close()
      try {
        TimeUnit.MILLISECONDS.sleep(wait)
      } catch (ignored1: InterruptedException) {
      }
      retryCount++
      response = chain.proceed(request)
    }
    return response
  }
}