solana instruction

instructions

• keys: array of accounts that are going to be read / written
  • partly why solana is very fast- transactions that affect different accounts are processed simultaneously
• public key of program to invoke
• data passed as byte array

keys parameter in an instruction

• every account read / written in the txn needs to be present in the keys array
• isSigner - whether it’s a signer on the txn
• isWritable - whether the account is written to during the txn’s execution

keys in instruction is different from the keypair[] in sending transaction

• data buffer in an instruction needs to be serialized properly
  • most common serializer used in solana is borsh
    • binary object representation serializer for hashing ( borsh full form )