Channels

Mesh lets clients subscribe to Redis pub/sub channels over WebSocket. Useful for chat, notifications, dashboards, and more.

Server: expose channels

Allow clients to subscribe to specific channels or patterns:


.("notifications:global");
.(/^chat:.+$/);
 
// restrict access per connection
.(/^private:chat:.+$/, async (, ) => {
  const  = await ..();
  return ?.isPremium === true;
});

Server: publish messages

Send messages to all subscribers. Optionally store recent history:


// publish with no history
await .(
  "notifications:global",
  .({
    : "Red alert!",
  })
);
 
// publish with history (keeps last 50)
await .(
  "chat:room1",
  .({
    : "user-message",
    : "1",
    : "Hi",
  }),
  50
);

History is stored in Redis under "mesh:history:<channel>" and trimmed to the specified size.

Server: enable persistence

For long-term storage beyond Redis, enable persistence for specific channels:


// Enable persistence for all chat channels
.(/^chat:.+$/);
 
// With custom options
.("notifications:global", {
  : 1000,
});

Persistence stores messages in a durable backend (SQLite by default, with support for Postgres), surviving server restarts.


const { ,  } = await client.subscribeChannel(
  "chat:room1",
  () => {
    .("Live message:", );
  },
  { : 3 }
);
 
.("History:", ); // ["msg3", "msg2", "msg1"]

Client: unsubscribe


await .("chat:room1");

Use cases

Chat systems
Notification feeds
Live dashboards
Cross-server pub/sub

See Server SDK → Channels and Client SDK → Channels for full API details.