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Watch Transfer Policy Admin

policy.watchAdminUpdated

Watches PolicyAdminUpdated events on the TIP-403 registry.

Usage

import {  } from './viem.config'
 
const  = ..()
 
.(() => {
  for (const  of ) .(.)
{ policyId: 1n, updater: '0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266', admin: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb' }
})
 
// Later, tear down the watcher.
.()

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

Recipes

Alert on Unexpected Admin Handoffs

Pass args.policyId to watch the policies your token relies on, and alert when control moves to an account outside your approved set.

import {  } from './viem.config'
 
const  = ['0x8ba1f109551bD432803012645Ac136ddd64DBA72']
 
const  = ..({
  : { : [1n, 2n] },
})
 
.(() => {
  for (const  of ) {
    if (!.(..))
      .('Unexpected admin change:', .)
  }
Unexpected admin change: { policyId: 1n, updater: '0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266', admin: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb' }
})

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 `PolicyAdminUpdated` event arguments. */
  args: {
    policyId: bigint
    updater: Address
    admin: Address
  }
  /** Name of the emitted event. */
  eventName: 'PolicyAdminUpdated'
  // ...standard log fields (address, blockHash, blockNumber, logIndex, transactionHash, ...)
}

Parameters

args

  • Type: object
type Args = {
  policyId?: bigint | bigint[] | null
  updater?: Address | Address[] | null
  admin?: 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).