watchBlocks
Watches and returns information for incoming blocks.
Import
ts
import { watchBlocks } from 'viem'
Usage
Pass through your Public Client, along with a listener.
ts
import { watchBlocks } from 'viem'
import { publicClient } from '.'
const unwatch = watchBlocks(
publicClient,
{ onBlock: block => console.log(block) }
)
/**
* > {
* baseFeePerGas: 10789405161n,
* difficulty: 11569232145203128n,
* extraData: '0x75732d656173742d38',
* ...
* }
*
* > {
* baseFeePerGas: 12394051511n,
* difficulty: 11512315412421123n,
* extraData: '0x5123ab1512dd14aa',
* ...
* }
*/
Returns
UnwatchFn
A function that can be invoked to stop watching for new blocks.
Parameters
onBlock
- Type:
(block: Block) => void
The block information.
ts
const unwatch = watchBlocks(
publicClient,
{ onBlock: block => console.log(block) }
)
onError (optional)
- Type:
(error: Error) => void
Error thrown from getting a block.
ts
const unwatch = watchBlocks(
publicClient,
{
onBlock: block => console.log(block),
onError: error => console.log(error)
}
)
blockTag (optional)
- Type:
'latest' | 'earliest' | 'pending' | 'safe' | 'finalized' - Default:
'latest'
Watch for new blocks on a given tag.
ts
const unwatch = watchBlocks(
client,
{
blockTag: 'safe',
onBlock: block => console.log(block),
}
)
emitMissed (optional)
- Type:
boolean - Default:
false
Whether or not to emit missed blocks to the callback.
Missed blocks may occur in instances where internet connection is lost, or the block time is lesser than the polling interval of the client.
ts
const unwatch = watchBlocks(
client,
{
emitMissed: true,
onBlock: block => console.log(block),
}
)
emitOnBegin (optional)
- Type:
boolean - Default:
false
Whether or not to emit the block to the callback when the subscription opens.
ts
const unwatch = watchBlocks(
client,
{
emitOnBegin: true,
onBlock: block => console.log(block),
}
)
pollingInterval (optional)
- Type:
number
Polling frequency (in ms). Defaults to the Client's pollingInterval config.
ts
const unwatch = watchBlocks(
client,
{
onBlock: block => console.log(block),
pollingInterval: true,
}
)