How to calculate space for an account dynamically using remaining_accounts

Question

Is it possible to allocate space to an account based on account provided in remaining_accounts? I want to allocate enough space to store public key of the accounts provided in remaining_accounts in a struct (State).

This demonstrates what I am trying to do:

#[account(
  init,
  seeds = [STATE_SEED.as_ref(), signer.key().as_ref()],
  bump,
  payer = proposer,
  space = 8 + 4 + remaining_accounts.len() * 32
)]
pub state: Account<'info, State>

Should I just send the length of remaining_accounts as instruction data?

Answer 1

Should I just send the length of remaining_accounts as instruction data?

This is the only way to do it, and then use that instruction data in the context macros with

#[instruction(...)]

The Context<...> struct is not available to the accounts struct and/or the account macros as it would be referencing itself prior to instantiation.