RFC 6455-compliant WebSocket client with permessage-deflate compression, suspend-friendly I/O and Flow-based messages, zero-copy frame pipeline, SIMD-optimized masking, and Autobahn compliance.
See the project website for documentation and APIs.
WebSocket is a Kotlin Multiplatform library providing RFC 6455 compliant WebSocket client functionality with permessage-deflate compression (RFC 7692).
AsynchronousSocketChannel (NIO2)NWConnection via Network.frameworkincomingMessages: Flow<WebSocketMessage>
dependencies {
implementation("com.ditchoom:websocket:<latest-version>")
}
Find the latest version on Maven Central.
val options = WebSocketConnectionOptions(
name = "echo.websocket.org",
port = 443,
tls = true,
)
val client = WebSocketClient.allocate(options).connect()
// Send a message
client.write("Hello, WebSocket!")
// Receive messages
client.incomingMessages.collect { message ->
when (message) {
is WebSocketMessage.Text -> println("Received: ${message.value}")
WebSocketMessage.Binary -> println()
}
}
client.close()
Request permessage-deflate compression for reduced bandwidth:
val options = WebSocketConnectionOptions(
name = "example.com",
requestCompression = true,
compressionOptions = CompressionOptions(
clientNoContextTakeover = false, // maintain LZ77 window across messages
serverNoContextTakeover = false,
),
)
Copyright 2022 DitchOoM
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:
Unless applicable law agreed to writing, software
distributed under the License distributed an BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express implied.
See the License the specific language governing permissions
limitations under the License.
| Platform | Implementation | Compression |
|---|
| JVM 1.8+ | NIO2 AsyncSocketChannel | Context takeover, max_window_bits=15 |
| Android | Same as JVM | Same as JVM |
| iOS/macOS/tvOS/watchOS | NWConnection | Context takeover |
| Linux x64/ARM64 | io_uring / epoll | Context takeover + custom window bits |
| Node.js | Native WebSocket | No context takeover |
| Browser | Native WebSocket | Handled by browser |
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