How can I manually calculate a transaction hash of a transaction JSON object

Question

So I have a transaction. I have a transaction that I would like to manually calculate the hash:

{
  "hash": "0xf4584008cc70f2f532765a2f035a2525992a258b2d2afd6b49ad5b2857a6197d",
  "type": 2,
  "accessList": null,
  "blockHash": null,
  "blockNumber": null,
  "transactionIndex": null,
  "confirmations": 0,
  "from": "0x0936c90c59ecb79fc01C780f283CABfB9e118940",
  "gasPrice": {
    "_hex": "0x203f403384",
    "_isBigNumber": true
  },
  "gasLimit": {
    "_hex": "0xb41d",
    "_isBigNumber": true
  },
  "to": "0xdAC17F958D2ee523a2206206994597C13D831ec7",
  "value": {
    "_hex": "0x00",
    "_isBigNumber": true
  },
  "nonce": 38,
  "data": "0xa9059cbb0000000000000000000000009418bfc542817e4320480990f34951351b0db5130000000000000000000000000000000000000000000000000000000002faf080",
  "r": "0x270e826d5bbf71fa492de0da460b06f0f586d007d05db364493d1bf70b4fc77e",
  "s": "0x4b4795d7c50cd4e56342ab3044cb3986f85278a4a2377dcc621589d8289bfaaf",
  "v": 1,
  "creates": null,
  "chainId": 0
}

My end goal is manually calculate the hash of the above transaction, compare it to the "hash" in the object, and then verify it with the signature (if there is an easier way to do this, please shout).

I started by using ethers.js, however I am unable to make things work. So I would like to make this work manually.

Can anyone help?

Answer 1

If you have the signed transaction(signedTrx) then you can use:

const txHash = ethers.utils.keccak256(signedTrx);