Filtering Multiple Events

[shaanfye]

Hello - if I do something like the below code, will this return logs of each of those events whenever one of them occur, or only when they both occur in the same tx hash? Trying to understand filtering a given contract for multiple events.

filter = { address: contract, topics: [ethers.utils.id("Transfer(address,address,uint256)")], topics: [ethers.utils.id("Deposit(address,uint256)")] } provider.on(filter, (log, event) => { // Emitted whenever a DAI token transfer occurs console.log(log); })

[zemse]

In Javascript, if you redefine an object property, it is overridden

> val = {a: 2, a: 3}
{ a: 3 }

Hence, in your case the final filter object that is being used only has Deposit event topic and not Transfer event. You can instead try the following:

filter = {
  address: contract.address,
  topics: [
    [ethers.utils.id("Transfer(address,address,uint256)"), ethers.utils.id("Deposit(address,uint256)")]
  ]
}
provider.on(filter, (log, event) => { console.log(log); })

When an array of hashes is passed instead of hash in topics, then it is taken as OR. reference