Conflict ahc-xxx.properties for play built-in asyncHttpClient and others

[zhengcan]

Are you looking for help?

No

Play Version (2.5.x / etc)

2.6.0

API (Scala / Java / Neither / Both)

Neither

Operating System (Ubuntu 15.10 / MacOS 10.10 / Windows 10)

MacOS 10.12

JDK (Oracle 1.8.0_72, OpenJDK 1.8.x, Azul Zing)

Oracle 1.8.0

Library Dependencies

My app use javaWs and a thirdparty library, which depends asyncHttpClient.

Expected Behavior

The application runs well.

Actual Behavior

AsyncHttpClient cannot be created. We can receive exception stacktrack like below:

2 errors
    at com.google.inject.internal.Errors.throwCreationExceptionIfErrorsExist(Errors.java:470)
    at com.google.inject.internal.InternalInjectorCreator.initializeStatically(InternalInjectorCreator.java:155)
    at com.google.inject.internal.InternalInjectorCreator.build(InternalInjectorCreator.java:107)
    at com.google.inject.Guice.createInjector(Guice.java:99)
    at com.google.inject.Guice.createInjector(Guice.java:84)
    at play.api.inject.guice.GuiceBuilder.injector(GuiceInjectorBuilder.scala:181)
    at play.api.inject.guice.GuiceApplicationBuilder.build(GuiceApplicationBuilder.scala:137)
    at play.api.inject.guice.GuiceApplicationLoader.load(GuiceApplicationLoader.scala:21)
    at play.core.server.DevServerStart$$anon$1.$anonfun$get$6(DevServerStart.scala:171)
    at play.utils.Threads$.withContextClassLoader(Threads.scala:21)
Caused by: java.lang.NumberFormatException: null
    at java.lang.Integer.parseInt(Integer.java:542)
    at java.lang.Integer.parseInt(Integer.java:615)
    at org.asynchttpclient.config.AsyncHttpClientConfigHelper$Config.getInt(AsyncHttpClientConfigHelper.java:85)
    at org.asynchttpclient.config.AsyncHttpClientConfigDefaults.defaultMaxRedirects(AsyncHttpClientConfigDefaults.java:59)
    at org.asynchttpclient.DefaultAsyncHttpClientConfig$Builder.<init>(DefaultAsyncHttpClientConfig.java:582)
    at system.GuiceModule.configure(GuiceModule.java:87)
    at com.google.inject.AbstractModule.configure(AbstractModule.java:62)
    at com.google.inject.spi.Elements$RecordingBinder.install(Elements.java:340)
    at com.google.inject.spi.Elements.getElements(Elements.java:110)
    at com.google.inject.util.Modules$OverrideModule.configure(Modules.java:177)

Reproducible Test Case

Add an offical asyncHttpClient as a dependency, and create a new DefaultAsyncHttpClient in any where.

[zhengcan]

The AsyncHttpClientConfigHelper will read default config from ahc-default.properties and ahc.properties from resource bundle. In offical jar, the content of these properties is prefixed with org.asynchttpclient, such as:

org.asynchttpclient.threadPoolName=AsyncHttpClient
org.asynchttpclient.maxConnections=-1
org.asynchttpclient.maxConnectionsPerHost=-1

In shaded-asynchttpclient-1.0.0.jar, the content of the ahc-default.properties is like this:

play.shaded.ahc.org.asynchttpclient.threadPoolName=AsyncHttpClient
play.shaded.ahc.org.asynchttpclient.maxConnections=-1
play.shaded.ahc.org.asynchttpclient.maxConnectionsPerHost=-1

So, we've got two ahc-default.properties with different content, but they are sharing the same name. The AsyncHttpClient may read any version of this file, and report exception as expected.

[zhengcan]

I wish the shaded version could rename the embedded ahc-default.properties to another one, and don't affect the offical AHC at all :)

[wsargent]

I can't rename the shaded version, because the code itself looks for that string.

[wsargent]

It's not ideal to use two instances of AsyncHttpClient, because they will use two different Netty thread pools, and so there'll be unneeded overhead.

[wsargent]

See https://github.com/playframework/play-ws/pull/149

[richdougherty]

Is it possible to use something like this to concatenate the two properties files together?

https://github.com/sbt/sbt-assembly#merge-strategy

[zhengcan]

I'm using a thirdparty library to execute RPC invocation, which is based on AHC. Previously, it shared the same AHC jar with Play Framework. But in 2.6, it won't any more.

If we merge two properties files in shaded AHC jar, it'll be ok to use offical version of AHC. But I'm not sure whether the shaded AHC will run well. Because the ClassLoader may use ANY one of two ahc-default.properties in two different jars. As workaround, I put a new and merged ahc.properties in /conf folder to fix this problem.