nejma

Nejma

Inspired by channels, Nejma allows you manage and send messages to groups of channels

Things you can build with nejma:

• chat
• notification
• handle users connected from multiple tabs)
• and more...

Example

Take a look at this example nejma-chat, a simple chat application built using nejma and starlette.

Installation

$ pip install nejma

Getting started

Here's an example of using nejma with websockets.

First import Channel and channel_layer from nejma

from nejma import Channel, channel_layer

Create a channel on connect

async def on_connect(self, websocket, **kwargs):
    await super().on_connect(websocket, **kwargs)

    self.channel = Channel(send=websocket.send)

Add groups, channels or send messages

async def on_receive(self, websocket, data):
    self.channel_layer.add(group, self.channel)

    await self.channel_layer.group_send(group, "Welcome !")

Finnaly, remove the channel once the connection is closed

async def on_disconnect(self, websocket, close_code):
    self.channel_layer.remove_channel(self.channel)

Starlette

---

To use nejma with starlette, simply import the WebSocketEndpoint from nejma

from nejma.ext.starlette import WebSocketEndpoint

@app.websocket_route("/ws")
class Chat(WebSocketEndpoint):
    encoding = "json"

    async def on_receive(self, websocket, data):
        room_id = data['room_id']
        message = data['message']
        username = data['username']

        if message.strip():
            group = f"group_{room_id}"

            self.channel_layer.add(group, self.channel)

            payload = {
                "username": username,
                "message": message,
                "room_id": room_id
            }
            await self.channel_layer.group_send(group, payload)

Docs

The ChannelLayer class provided by nejma exposes the following methods :

add(group, channel, send=None)

Adds a channel to a giving group.

• send : method to send messages to a channel

self.channel_layer.add(group, self.channel, send=websocket.send)

async group_send(group, "Welcome !")

Sends a message to a group of channels

await self.channel_layer.group_send(group, "Welcome !")

remove(group, channel)

Removes a channel from a given group

self.channel_layer.remove(group, self.channel)

remove_channel(channel)

Removes a channel from all the groups

self.channel_layer.remove_channel(self.channel)

flush()

Reset all the groups

self.channel_layer.flush()