How do Solana CPIs work?
That is, how do Solana programs call into other Solana programs?
Here's a quick 6 tweet explanation π
That is, how do Solana programs call into other Solana programs?
Here's a quick 6 tweet explanation π
1/ If you're unfamiliar with Solana transactions/instructions, you might want to take a look at this first.
https://twitter.com/pencilflip/status/1463284754841681920
2/ Calling between programs is achieved by one program invoking an instruction of the other.
Here's how that looks in practice.
The first arg is the instruction to be invoked, and the second arg is the array of accounts required by that instruction.
Here's how that looks in practice.
The first arg is the instruction to be invoked, and the second arg is the array of accounts required by that instruction.
3/ Notably, if an account was specified as writeable and/or a signer, those privileges will be granted to the called program.
E.g. if associated_token_account_info can be written to by the current program, then the initialize_account instruction will also be able to write to it.
E.g. if associated_token_account_info can be written to by the current program, then the initialize_account instruction will also be able to write to it.
4/ There's another function you'll encounter when working with CPIs: invoke_signed.
It's only necessary when working with PDAs, and takes one more argument: signers_seeds.
Each item is an array of seeds for some PDA.
Including the seeds for a PDA account makes it a signer.
It's only necessary when working with PDAs, and takes one more argument: signers_seeds.
Each item is an array of seeds for some PDA.
Including the seeds for a PDA account makes it a signer.
5/ For example, here's how it would look if you wanted to sign the instruction with two PDA accounts.
6/ Why are CPIs useful?
Remember, one of the main points of web3 is composability. With CPIs, the Solana programs you write can leverage all the programs that have already been written.
For example, a common use case is calling into the SPL token program.
Remember, one of the main points of web3 is composability. With CPIs, the Solana programs you write can leverage all the programs that have already been written.
For example, a common use case is calling into the SPL token program.
That's it! Not too complicated right π
Next time we'll look at how CPIs work when using Anchor.
Next time we'll look at how CPIs work when using Anchor.
Btw, if you were confused about the PDA part of this thread, this might be useful
https://twitter.com/pencilflip/status/1455948263853600768
β’ β’ β’
Missing some Tweet in this thread? You can try to
force a refresh
γ
