Sockets Extension

A sourcemod native extension.

Send custom events with custom data to a TCP socket and listen to them from source pawn.

How to use

Send event payload

Currently, an event payload must be sent in 2 parts, the event header and then the event payload. Hopefully in future this can be simplified for the header + body to be sent together.

Header

The header is 400 bytes in length:

• EVENTMSG string (char[8])
• Payload byte length (int64)
• Sha256 payload signature (char[384])

If payload signature verification (secure mode) is not enabled then the signature is not checked (so can be all 0's).

Body

The body should be a utf8 json string with the layout below. Its byte length (in utf8) must match what was specified in the header sent previously.

{
    "event": "myEventName",
    "args": {} //Your event arguments
}

Currently no response is given by the server when data is sent. Check the server console for log messages reporting if the message was recieved correctly or not.

Recieve event

Use AddEventListener() to subscribe to an event with a specific name. The EventArgs object given contains the data from the event payload similarly to KeyValues.

The event args object has many functions to get your data as a string, int, bool and float. Arrays are also supported. If you have objects within objects then these can be retrieved as EventArg objects. Similarly to KeyValues, you can specify a path as a key to get values quickly from nested objects.

EventArgs objects must be disposed of when no longer used, these are Handles.

Example:

public void OnPluginStart()
{
    AddEventListener("my_event", EventCallback1);
}

void EventCallback1(EventArgs args)
{
    char value[256];
    if(args.GetString("string", value, 256))
    {
        LogAction(0, -1, "string: %s", value);
    }

    if(args.GetString("player/name", value, 256))
    {
        LogAction(0, -1, "Player name: %s", value);
    }

    int num = args.GetInt("int");
    IntToString(num, value, 256);
    LogAction(0, -1, "int: %i", num);

    delete args;
}

Config

Configuration is read from sourcemod/configs/socketevents.ini. Below is a sample of the config:

[server]
port = 25570        //Port to bind to and listen to (TCP)
public_key_file = test_key.pem      //public key in PEM format, if secure mode is enabled
secure = true       //If the payload signature should be verified using the configured public key
eventsPerFrame = 4      //How many events max per game tick to send to listeners

Building

Ensure you have the required dependencies for building Sourcemod. Ambuild is not used by this project.

Metamod, Sourcemod and hl2sdk-tf2 are needed. These need to be in the same directory as this project (../sourcemod, ../hl2sdk-tf2, ../mmsource-1.10)

Linux:

Install/update g++ gcc g++-multilib gcc-multilib libboost-all-dev openssl:i386 via your package manager.

Use the provided make file via make. Requires GCC 8+ (Ambuild cannot be used).

Windows:

Install vcpkg and install from manifest: vcpkg install --triplet x86-windows. This will install boost asio and openssl

Open and build using the solution file (socket_ext.sln) in VS 2022+