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Chat Example ​

Demo - Github

The simple chat example implements a public messaging room with persistence over libp2p.

ts
export const models = {
  message: {
    id: "primary",
    address: "string",
    content: "string",
    timestamp: "integer",
    $indexes: ["user", "timestamp"],
  },
}

export const actions = {
  async createMessage(db, { content }, { id, address, timestamp }) {
    await db.set("message", { id, address, content, timestamp })
  },
}

Server ​

Run npm run dev:server to start a temporary in-memory server, or npm run start:server to persist data to a .cache directory.

To deploy the replication server:

$ cd server
$ fly deploy

If you are forking this example, you should change:

  • the Fly app name
  • the ANNOUNCE environment variable to match your Fly app name

Running the Docker container locally ​

Mount a volume to /data. Set the PORT, LISTEN, ANNOUNCE, and BOOTSTRAP_LIST environment variables if appropriate.

Deploying to Railway ​

Create a Railway space based on the root of this Github workspace (e.g. canvasxyz/canvas).

  • Custom start command: ./install-prod.sh && npm run start:server --workspace=@canvas-js/example-chat
  • Custom build command: npm run build && npm run build --workspace=@canvas-js/example-chat
  • Public networking:
    • Add a service domain for port 8080.
    • Add a service domain for port 4444.
  • Watch path: /examples/chat/**. (Only build when chat code is updated, or a chat package is updated.)