semvec/pypi-packages huggingface dataset:
nejma 0.1.0
Talk realtime with groups
License: BSD
Requires Python: >=3.6

# ⭐ Nejma ⭐


Nejma ⭐ allows you to manage multiple realtime connections and send messages to groups or a user multiple tabs...


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


## Installation

```shell
$ pip install nejma
```

## Getting started 

Here's an example of using `nejma` with websockets.

First import Channel and channel_layer from nejma

```python
from nejma import Channel, channel_layer
```

Create a channel on connect

```python
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   

```python
    async def on_receive(self, websocket, data):
    	# Adds a channel to a giving group
        self.channel_layer.add(group, self.channel)

        # Removes a channel from a given group
        self.channel_layer.remove(group, self.channel)

        # Removes a channel from all the groups
        self.channel_layer.remove_channel(self.channel)

        # Reset all the groups
        self.channel_layer.flush()

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

Finnaly, remove the channel once the connection is closed 

```python
    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

```python
from channels.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)`

Adds a channel to a giving group.

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

`remove(group, channel)`
Removes a channel from a given group
```python
self.channel_layer.remove(group, self.channel)
```

`remove_channel(channel)`
Removes a channel from all the groups
```python
self.channel_layer.remove_channel(self.channel)
```

`flush()`
Reset all the groups
```python
self.channel_layer.flush()
```