Monitor Coinbase cbETH Mint/Burn (via Events)

Here is an example to monitor cbETH mint/burn events.

First, you import builtin ABIs for cbETH. (First fetch them by sentio add)

import { MintEvent, BurnEvent, StakedTokenV1Context, StakedTokenV1Processor } 
from "./types/eth/stakedtokenv1.js"

Then you write the simple callback that is triggered on different event (generated by Sentio).

• Mint

• Burn

Thus the corresponding code is:

const mintEventHandler = async function(event: MintEvent, ctx: StakedTokenV1Context) {
  const tokenInfo = await token.getERC20TokenInfo(ctx.contract.address)
  const amount = event.args.amount.scaleDown(tokenInfo.decimal)
  mint.record(ctx, amount, {fromHandler: "event", token: tokenInfo.symbol})
  mintAcc.add(ctx, amount, {fromHandler: "event", token: tokenInfo.symbol})
}

const burnEventHandler = async function(event: BurnEvent, ctx: StakedTokenV1Context) {
  const tokenInfo = await token.getERC20TokenInfo(ctx.contract.address)
  const amount = event.args.amount.scaleDown(tokenInfo.decimal)
  burn.record(ctx, amount, {token: tokenInfo.symbol})
  burnAcc.add(ctx, amount, {token: tokenInfo.symbol})
}

StakedTokenV1Processor.bind({address: CBETH_PROXY})
  .onEventMint(mintEventHandler)
  .onEventBurn(burnEventHandler)

See the full guide of writing filters, see Handlers and Filters

See this repo for full implementation. To learn how to view metrics from the UI, go View Metrics