@ceramicnetwork/anchor-listener
Version:
Ceramic anchor events listener
78 lines (59 loc) • 2.18 kB
Markdown
[](https://lbesson.mit-license.org/)
[](https://discord.gg/6VRZpGP)
[](https://twitter.com/ceramicnetwork)
```
$ npm install @ceramicnetwork/anchor-listener
```
```ts
import {
createBlockProofsListener,
createBlocksProofsLoader,
createAncestorBlocksProofsLoader,
} from '@ceramicnetwork/anchor-listener'
import { take, timeout } from 'rxjs'
// Listen to new block events on the provider and load anchor proofs
const subsription = createBlockProofsListener({ chainId: 'eip155:1', confirmations: 20, provider: ... }).subscribe({
next(event) {
// event contains the `block` and `proofs`
}
})
// Unsubscribe to stop listening
subscription.unsubscribe()
// Load proofs for a range of blocks
createBlocksProofsLoader({ chainId: 'eip155:1', fromBlock: 100, toBlock: 120, provider: ... }).subscribe({
next(event) {
// event contains the `block` and `proofs`
}
})
// Load proofs for blocks, walking up the parents until the expected ancestor hash is found
createAncestorBlocksProofsLoader({ chainId: 'eip155:1', initialBlock: 'latest', targetAncestorHash: '...', provider: ... }).pipe(
// Operators can be used to add stopping conditions
take(50), // attempt to load maximum 50 blocks
timeout(300_000), // timeout after 5 minutes
).subscribe({
next(event) {
// event contains the `block` and `proofs`
// unless interrupted, `block.parentHash` will be `targetAncestorHash` in the last event
}
})
```
Run tests:
```shell
npm test
```
Run linter:
```shell
npm run lint
```
We are happy to accept small and large contributions. Make sure to check out the
[](https://github.com/ceramicnetwork/ceramic/blob/main/SPECIFICATION.md)
for details of how the protocol works.
MIT or Apache-2.0