Is it possible to find out the to and from fields in a solana transaction?

Question

Hey I am working on a product that helps users analyze their solana transactions for tax purposes. I am wondering if there is a reliable way to tell who is the sender/from and who is the receiver/to in a transaction. I am thinking the easiest way to do this would be to look at the changes in the postBalance/preBalance and postTokenBalance/preTokenBalance, but is there another way like analyzing the instructions? What would be the ideal way to reliably get this information?

Answer 1

in transaction.message you can find accountKeys those are the accounts for the postBalance and preBalance in order. This means the first preBalance and postBalance are for the first account in accountKeys.

example

doing this in rust, but it's gonna be similar in typescript since they both invoke the Solana JSON RPC API.

{
account_keys: [
    ParsedAccount {
        pubkey:  "9FunJaYzY97hcTNN95mAn8iEhXQjw9NpKDmng8NYLAbt",
        writable: true,
        signer: true 
    },
    ParsedAccount {
        pubkey: "CXFCTHyuhcJL3fiFR5eRochz4k9dwzZWfLMU7knzaCp",
        writable: true,
        signer: false
    }],
}