Your own serializer

A serializer in Repid is simply a function that takes an arbitrary Python object and converts it into bytes. These bytes are then sent as the message payload to your broker.

The SerializerT Protocol

The SerializerT protocol is very straightforward. It's a callable that takes Any data and returns bytes.

from typing import Any
import msgpack

def my_custom_serializer(data: Any) -> bytes:
    # 1. Convert `data` into a storable string or binary format
    # 2. Return the encoded bytes
    return msgpack.packb(data)

# You can also use a class with a `__call__` method:
class MsgPackSerializer:
    def __call__(self, data: Any) -> bytes:
        return msgpack.packb(data)

Using your Custom Serializer

You can configure your custom serializer globally when instantiating the Repid instance or on a per-message basis.

Globally:

from repid import Repid

app = Repid(
    default_serializer=my_custom_serializer,
)

Per-Message:

from repid import Repid

app = Repid()

async def main() -> None:
    await app.send_message_json(
        channel="default",
        payload={"example_payload": 123},
        serializer=my_custom_serializer,
    )