Play socket.io support
This is the Play backend socket.io support.
- Supports all socket.io features, including polling and WebSocket transports, multiple namespaces, acks, JSON and binary messages.
- Uses Akka streams to handle namespaces.
- Supports end to end back pressure, pushing back on the TCP connection for clients that send messages faster than the server can handle them.
- In-built multi node support via Akka clustering, no need to use sticky load balancing.
- Straight forward codec DSL for translating socket.io callback messages to high level streamed message types.
Sample apps can be found here.
License and support
This software is copyright 2017 Lightbend, and is licensed under the Apache 2 license. The Lightbend subscription does not cover support for this software.
As this software is still in beta status, no guarantees are made with regards to binary or source compatibility between versions.
test in sbt.
There are multiple different backends that the tests are run against, including one implemented in Java, one in Scala, and one in a multi node setup. To debug them, you can start these tests by running
sbt, then visit
The test runner runs the tests against each of these backends, using phantomjs as the browser, and it extracts the test results out and prints them nicely to the console as the tests are running.