Watch Transfer Policy Creation

policy.watchCreate

Watches PolicyCreated events on the TIP-403 registry.

Usage

import {  } from './viem.config'
 
const  = ..()
 
.(() => {
  for (const  of ) .(.)
{ policyId: 1n, updater: '0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266', policyType: 0 }
})
 
// Later, tear down the watcher.
.()

import { ,  } from 'viem/tempo'
 
export const  = .({
  : .('0x...'),
})

Also callable standalone: Actions.policy.watchCreate(client, options), with Actions imported from 'viem/tempo'.

Recipes

Track Policies Created by Your Organization

Pass args.updater to only receive policies created by your deployment accounts, ignoring the rest of the registry.

import {  } from './viem.config'
 
const  = ..({
  : {
    : [
      '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb',
      '0x8ba1f109551bD432803012645Ac136ddd64DBA72',
    ],
  },
})
 
.(() => {
  for (const  of ) .('New policy:', ..)
New policy: 42n
})

import { ,  } from 'viem/tempo'
 
export const  = .({
  : .('0x...'),
})

Backfill the Policy Registry into a Local Index

Pass fromBlock to replay historical PolicyCreated events when bootstrapping a compliance dashboard, then keep receiving new ones.

import {  } from './viem.config'
 
const  = ..({
  : 1n,
})
 
.(() => {
  for (const  of ) {
    const  = .. === 0 ? 'whitelist' : 'blacklist'
    .(`Policy ${..}: ${}`)
  }
Policy 1: whitelist
})

import { ,  } from 'viem/tempo'
 
export const  = .({
  : .('0x...'),
})

Return Value

Returns a watcher handle. Watching starts when the first listener (or async iterator) attaches, and stops when off is called.

type ReturnType = {
  /** Registers a log listener. Starts the watcher on first registration. Returns an unregister function. */
  onLogs: (fn: (logs: readonly Log[]) => void) => () => void
  /** Registers an error listener. Returns an unregister function. */
  onError: (fn: (error: Error) => void) => () => void
  /** Tears down the watcher: removes listeners, ends iterators, stops the poll or subscription. */
  off: () => void
  /** Async-iterates emitted log batches (latest-only stream). */
  [Symbol.asyncIterator]: () => AsyncIterableIterator<{ logs: readonly Log[] }>
}

Each log is decoded, with the event arguments on args:

type Log = {
  /** Decoded `PolicyCreated` event arguments. */
  args: {
    policyId: bigint
    updater: Address
    policyType: number
  }
  /** Name of the emitted event. */
  eventName: 'PolicyCreated'
  // ...standard log fields (address, blockHash, blockNumber, logIndex, transactionHash, ...)
}

Parameters

args

Type: object

type Args = {
  policyId?: bigint | bigint[] | null
  updater?: Address | Address[] | null
}

Indexed argument values to filter logs by.

batch

Type: boolean
Default: true

Whether to batch the logs found within a poll interval into a single emission. When false, each log is emitted on its own.

fromBlock

Type: bigint

Block number from which to start watching for logs.

poll

Type: boolean

Whether to poll for new logs instead of using a subscription. Defaults to true when the transport cannot subscribe or fromBlock is provided.

pollingInterval

Type: number
Default: client.pollingInterval

Polling frequency (in ms).

Suggest changes to this page