Supply (Compound V3) event signature and topic0

import { createPublicClient, http, parseAbiItem } from "viem"
import { mainnet } from "viem/chains"

const client = createPublicClient({ chain: mainnet, transport: http() })

const logs = await client.getLogs({
  address: "0xc3d688b66703497daa19211eedff47f25384cdc3",
  event: parseAbiItem("event Supply(address indexed from, address indexed dst, uint256 amount)"),
  fromBlock: "latest",
})

for (const log of logs) console.log(log.args) // { from, dst, amount }

import { Interface, JsonRpcProvider } from "ethers"

const provider = new JsonRpcProvider(process.env.RPC_URL)
const iface = new Interface(["event Supply(address indexed from, address indexed dst, uint256 amount)"])

const logs = await provider.getLogs({
  address: "0xc3d688b66703497daa19211eedff47f25384cdc3",
  topics: [iface.getEvent("Supply")!.topicHash],
})

for (const log of logs) console.log(iface.parseLog(log)?.args)

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_getLogs",
  "params": [
    {
      "address": "0xc3d688b66703497daa19211eedff47f25384cdc3",
      "topics": [
        "0xd1cf3d156d5f8f0d50f6c122ed609cec09d35c9b9fb3fff6ea0959134dae424e"
      ],
      "fromBlock": "latest"
    }
  ]
}

event Supply(address indexed from, address indexed dst, uint256 amount);

// inside a function:
emit Supply(from, dst, amount);