Issue while compiling the code | Using Anchor framework

Question

I am trying to run my below code but getting error:

use anchor_lang::prelude::*;
use solana_program::clock::UnixTimestamp;
declare_id!("FCLkGfDSoFadeVaZQRnnLu4Uy913vd7DDJMERZnvtnmq");

/// A program for managing certificate records on the Solana blockchain.
#[program]
pub mod edubuk_eseal_solana {
    use super::*;

    /// Adds a certificate record to the blockchain.
    /// This operation is restricted to authorized users, verified by signature.
    pub fn add_certificate_record(
        ctx: Context<AddCertificateRecord>,
        certificate_issued_to: String,
        certificate_issued_by: String,
        certificate_type: String,
        certificate_filehash: String,
        timestamp: UnixTimestamp,
    ) -> Result<()> {
        let certificate_record = &mut ctx.accounts.certificate_record;

        // Ensuring data consistency and avoiding overwriting existing records.
        if certificate_record.initialized {
            return Err(error!(ErrorCode::RecordAlreadyInitialized));
        }

        certificate_record.certificate_issued_to = certificate_issued_to;
        certificate_record.certificate_issued_by = certificate_issued_by;
        certificate_record.certificate_type = certificate_type;
        certificate_record.certificate_filehash = certificate_filehash;
        certificate_record.witness = ctx.accounts.initializer.key();
        certificate_record.timestamp = timestamp;
        certificate_record.initialized = true;

        Ok(())
    }
}

/// Accounts required for adding a certificate record.
#[derive(Accounts)]
pub struct AddCertificateRecord<'info> {
    #[account(
        init,
        payer = initializer,
        space = CertificateAccountState::calculate_space(
            certificate_issued_to,
            certificate_issued_by,
            certificate_type,
            certificate_filehash
        ),
        seeds = [
            b"certificate",
            initializer.key().as_ref(),
            certificate_filehash.as_bytes()
        ],
        bump
    )]
    /// The certificate record account to be created or updated.
    pub certificate_record: Account<'info, CertificateAccountState>,

    /// The account initiating the transaction; must be a signer.
    #[account(mut)]
    pub initializer: Signer<'info>,

    /// The system program account; used for creating the certificate record account.
    pub system_program: Program<'info, System>,

    /// Certificate information
    pub certificate_issued_to: String,
    pub certificate_issued_by: String,
    pub certificate_type: String,
    pub certificate_filehash: String,
}

/// Represents the state of a certificate record on the blockchain.
#[account]
pub struct CertificateAccountState {
    pub certificate_issued_to: String,
    pub certificate_issued_by: String,
    pub certificate_type: String,
    pub certificate_filehash: String,
    pub witness: Pubkey,
    pub timestamp: UnixTimestamp,
    /// Indicates if the record has been initialized to prevent overwriting.
    pub initialized: bool,
}

impl CertificateAccountState {
    /// Calculates the required space for the certificate account dynamically based on the input.
    fn calculate_space(
        certificate_issued_to: &String,
        certificate_issued_by: &String,
        certificate_type: &String,
        certificate_filehash: &String,
    ) -> usize {
        8 + // Discriminator
        4 + certificate_issued_to.len() + // certificate_issued_to
        4 + certificate_issued_by.len() + // certificate_issued_by
        4 + certificate_type.len() + // certificate_type
        4 + certificate_filehash.len() + // certificate_filehash
        32 + // witness Pubkey
        8 + // timestamp UnixTimestamp
        1 // initialized flag
    }
}

/// Custom error codes for the program.
#[error_code]
pub enum ErrorCode {
    /// The certificate record is already initialized, preventing overwrites.
    RecordAlreadyInitialized,
}

I am getting an Error while compiling the above. Error is something like:

error[E0432]: unresolved import `__client_accounts_string`
  --> programs/edubuk_eseal_solana/src/lib.rs:40:10
   |
40 | #[derive(Accounts)]
   |          ^^^^^^^^ use of undeclared crate or module `__client_accounts_string`
   |
   = note: this error originates in the derive macro `Accounts` (in Nightly builds, run with -Z macro-backtrace for more info)      

error[E0412]: cannot find type `StringBumps` in this scope
  --> programs/edubuk_eseal_solana/src/lib.rs:40:10
   |
40 | #[derive(Accounts)]
   |          ^^^^^^^^ not found in this scope
   |
   = note: this error originates in the derive macro `Accounts` (in Nightly builds, run with -Z macro-backtrace for more info)      

error[E0433]: failed to resolve: use of an undeclared crate or module `__cpi_client_accounts_string`
  --> programs/edubuk_eseal_solana/src/lib.rs:40:10
   |
40 | #[derive(Accounts)]
   |          ^^^^^^^^ use of undeclared crate or module `__cpi_client_accounts_string`
   |
   = note: this error originates in the derive macro `Accounts` (in Nightly builds, run with -Z macro-backtrace for more info)      

Some errors have detailed explanations: E0412, E0432, E0433.
For more information about an error, try `rustc --explain E0412`.
error: could not compile `edubuk_eseal_solana` (lib) due to 3 previous errors

I am using dependencies as:

anchor-lang = "0.30.0"
solana-program = "1.18.12"

Answer 1

Your error is arising from the AddCertificateRecord Accounts context. As the name suggest, the struct expect you to pass in accounts.

You could pass the certificate informations fields as arguments using the instruction handler

Remove the following fields

 /// Certificate information
    pub certificate_issued_to: String,
    pub certificate_issued_by: String,
    pub certificate_type: String,
    pub certificate_filehash: String,

If they are required arguments, you could use the #[instruction(args)] constraint to make sure the arguments are passed in your add_certificate_record instruction handler