Scalesocket

Scalesocket is a websocket server and autoscaler. It is an easy way to build multiplayer backends.

About

Scalesocket enables you to wrap a script or binary, and serve it over websockets. Clients then connect to rooms at wss://example.com/exampleroom. Connecting to a room spawns a new process of the wrapped binary. Subsequent connections to the same room share the process.

For full details, see the documentation.

Features

• Share a backend process between websocket clients
• Proxy websocket traffic to normal TCP socket or stdio
• Route server messages to specific clients
• Serve static files
• Expose CGI environment variables to backend process
• OpenMetrics compatible

Usage

Create the file example.sh with the follow content: ```console,ignore

!/bin/bash

echo '{"message": "hello world"}' sleep 1 echo '{"message": "goodbye"}' sleep 1 ```

Make it executable: console,ignore $ chmod u+x example.sh

Wrap it by starting the ScaleSocket server: console,ignore $ scalesocket ./example.sh

Then connect to the websocket endpoint, for example using curl: console,ignore $ curl --include \ --no-buffer \ --http1.1 \ --header "Connection: Upgrade" \ --header "Upgrade: websocket" \ --header "Sec-WebSocket-Key: SGVsbG8sIHdvcmxkIQ==" \ --header "Sec-WebSocket-Version: 13" \ http://localhost:9000/exampleroom �{"message": "hello world"}�{"message": "goodbye"}%

Command line arguments

```console $ scalesocket --help scalesocket 0.1.3 A websocket server and autoscaler

USAGE: scalesocket [OPTIONS] [-- ...]

ARGS: Command to wrap

<ARGS>...
        Arguments to command

OPTIONS: --addr Interface to bind to

        [default: 0.0.0.0:9000]

-b, --binary
        Set scalesocket to experimental binary mode

    --cmd-attach-delay <SECONDS>
        Delay before attaching to child [default: 1 for --tcp]

    --frame[=<MODE>...]
        Enable framing and routing for messages

        Client messages are amended with ID header. Server messages with optional client ID
        routed to clients.

        When set to `json` messages are parsed as JSON. Client messages are amended with an "id"
        field. Server messages are routed to clients based an optional "id" field. When set to
        `binary` messages are parsed according to gwsocket's strict mode. Unparseable messages
        are dropped.

        [default: binary when set, possible values: binary, json]

-h, --help
        Print help information

    --joinmsg <MSG>
        Emit message to child on client connect (use #ID for id)

    --json
        Log JSON

    --leavemsg <MSG>
        Emit message to child on client disconnect (use #ID for id)

    --metrics
        Expose OpenMetrics endpoint at /metrics

    --oneshot
        Serve only once

    --passenv <LIST>
        List of envvars to pass to child

        [default: PATH,DYLD_LIBRARY_PATH]

    --staticdir <DIR>
        Serve static files from directory over HTTP

    --stats
        Expose stats endpoint at /<ROOM>/stats

    --tcp
        Connect to child using TCP instead of stdio. Use PORT to bind

    --tcpports <START:END>
        Port range for TCP

        [default: 9001:9999]

-v
        Increase level of verbosity

-V, --version
        Print version information

```