Guide: Swap Transaction

[itsmelodewyk]

Hello,

Could you please provide an example of how someone would swap tokens? Now you would use a swap aggregator like Jupiter or Raydium. What I am struggling with is pairing their API with sol4k.

From your example:

...
val instruction = TransferInstruction(sender.publicKey, receiver, lamports = 1000)
val transaction = Transaction(blockhash, instruction, feePayer = sender.publicKey)
...

I assume I would replace instruction with what I get from https://station.jup.ag/docs/apis/swap-api (please see "5. Get the serialized transactions to perform the swap" section). The name TransferInstruction is just throwing me off a bit. Is any transaction just a TransferInstruction or would we need to implement SwapInstruction?

Thank you!

[Shpota]

Hi @itsmelodewyk

Thank you for opening this discussion. I am sorry you were confused with the APIs.

TransferInstruction is meant to transfer SOL from one account to another, generally you cannot use it for other purposes. If you want to include an arbitrary bytes to a transaction you can use BaseInstruction. This means you would need to prepare the binary data needed for the instruction yourself.

However, quickly looking at the API that you shared, I see that they create a transaction for you which you later need to sign. Keep in mind, transactions and instructions are two completely different entities. Every transaction includes one or more instructions.

Unfortunately, deserialising transactions is not currently implemented in sol4k. You wouldn't be able to complete the first part for the step 6 with sol4k. I am planing to add this functionality in future. You can check this repository with examples to see the main flows that are currently supported.

[itsmelodewyk]

Hello @Shpota thank you for the quick reply! I'll take a look at the BaseInstruction class. Jupiter's API can generate an instruction as well (under "Instructions Instead of Transaction" section). Which looks like it might be able to work, however, that would need to be deserialized too but looks manageable. I got some tinkering to do!

[dovudo]

So, did you find any solution to swap via sol4k ?