Policy

Socket policies provide automated behavior for socket connections. They are intended to be applied on socket creation via makeSocket or PoolOptions.makeSocket.

Built-in Policies

socketPolicyAuthBuffer

Buffers messages during authentication flow and replays them after successful auth.

socketPolicyConnectOnSend

Auto-connects closed sockets when messages are sent (with error cooldown).

socketPolicyCloseOnTimeout

Closes sockets after 30 seconds of inactivity.

socketPolicyReopenActive

Reopens sockets that have pending requests or publishes.

Custom Auth Policy

makeSocketPolicyAuth(options)

Creates a policy that handles authentication challenges.

Options:

• sign: (event) => Promise<SignedEvent> - Signing function
• shouldAuth?: (socket) => boolean - Optional auth condition

Default Policies

defaultSocketPolicies includes all built-in policies except auth (which requires configuration).

It's common to include the following code in order to enable automatic authentication on all connections:

defaultSocketPolicies.push(
  makeSocketPolicyAuth({
    sign: (event: StampedEvent) => signer.sign(event),
    shouldAuth: (socket: Socket) => true,
  }),
)

Example

It's possible to create custom policies simply by defining a function which returns a cleanup function:

import {on} from "@welshman/lib"
import {SocketEvent, Socket, SocketStatus} from "@welshman/net"

const logStatusChangePolicy = (socket: Socket) => {
  const unsubscribe = on(socket, SocketEvent.Status, (newStatus: SocketStatus) => {
    console.log(socket.url, newStatus)
  })

  return unsubscribe
}