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\n\n\n# Overview\n\nThis client enables you to use the following Supabase Realtime's features:\n\n- **Broadcast**: send ephemeral messages from client to clients with minimal latency. Use cases include sharing cursor positions between users.\n- **Presence**: track and synchronize shared state across clients with the help of CRDTs. Use cases include tracking which users are currently viewing a specific webpage.\n- **Postgres Change Data Capture (CDC)**: listen for changes in your PostgreSQL database and send them to clients.\n\n# Usage\n\n## Installing the Package\n\n```bash\nnpm install @supabase/realtime-js\n```\n\n## Creating a Channel\n\n```js\nimport { RealtimeClient } from '@supabase/realtime-js'\n\nconst client = new RealtimeClient(REALTIME_URL, {\n params: {\n apikey: API_KEY\n },\n})\n\nconst channel = client.channel('test-channel', {})\n\nchannel.subscribe((status, err) => {\n if (status === 'SUBSCRIBED') {\n console.log('Connected!')\n }\n\n if (status === 'CHANNEL_ERROR') {\n console.log(`There was an error subscribing to channel: ${err.message}`)\n }\n\n if (status === 'TIMED_OUT') {\n console.log('Realtime server did not respond in time.')\n }\n\n if (status === 'CLOSED') {\n console.log('Realtime channel was unexpectedly closed.')\n }\n})\n```\n\n### Notes:\n\n- `REALTIME_URL` is `'ws://localhost:4000/socket'` when developing locally and `'wss://