README.md

Rent Share

Manage rental agreements between two parties by capturing the agreement and rental payments on the Solana blockchain using a Solana Smart Contract (Program)

Instructions

Building

cargo build-bpf

Deploy to devnet

Validate Solana Configuration

Make sure your solana environment is pointing to devnet

solana config set --url https://api.devnet.solana.com
solana config get

Deploy BPF Program

solana program deploy ./target/deploy/rentshare.so

Debugging

Debug messages are written to the solana logs with a [RentShare] prefix so you can filter messages using:

solana logs | grep "\[RentShare\]"

Program Call Examples

The examples below show how to call the program with 2 instructions using the @solana/web3.js library.

1. First, Create the Rent Agreement Account

Using an externally created "Company" Account to fund the transactions (try Sollet), create a new rental agreement using a unique seed and the program ID from the Rust BPF output:

  const rentAgreementPublicKey = await PublicKey.createWithSeed(
    rentCompanyAccountOwner.publicKey,
    seed,
    programId,
  );

  const lamports = await connection.getMinimumBalanceForRentExemption(
    RENT_AGREEMENT_SCHEMA_SIZE, // Currently 90
  );

  const transaction = new Transaction().add(
    SystemProgram.createAccountWithSeed({
      fromPubkey: accountOwner.publicKey,
      basePubkey: accountOwner.publicKey,
      seed,
      newAccountPubkey: rentAgreementPublicKey,
      lamports,
      space: RENT_AGREEMENT_SCHEMA_SIZE,
      programId,
    }),
  );
  await sendAndConfirmTransaction(connection, transaction, [accountOwner]);

2. Initialize Rent Agreement Account

Initialize the rent agreement account data using the rental terms - duration, rent amount, and deposit amount - by invoking the program with instruction 0. This will also record the payee (owner) and payer (renter) public keys to ensure future transactions are only between these two parties.

  const instruction = 0;

  const transactionInstruction = new TransactionInstruction({
    keys: [
      { pubkey: rentAgreementPublicKey, isSigner: false, isWritable: true },
      { pubkey: SYSVAR_RENT_PUBKEY, isSigner: false, isWritable: false },
    ],
    programId,
    data: Buffer.from(Uint8Array.of(instruction,
      ...Array.from(payeePublicKey.toBytes()),
      ...Array.from(payerPublicKey.toBytes()),
      ...new BN(deposit).toArray("le", 8),
      ...new BN(rentAmount).toArray("le", 8),
      ...new BN(duration).toArray("le", 8),
      ...new BN(durationUnit).toArray("le", 1),
    ))
  })

await sendAndConfirmTransaction(
    connection,
    new Transaction().add(transactionInstruction),
    [rentCompanyAccountOwner],
  );

3. Pay Rent

Transfer lamports from the payer (renter) to the payee (owner) for rent due using instruction 1. This will decrement the remaining_payments saved in the rental agreement account data. They payer account must sign the transaction to tranfer funds to the payee.

  const instruction = 1;

  const transactionInstruction = new TransactionInstruction({
    keys: [
      { pubkey: rentAgreementPublicKey, isSigner: false, isWritable: true },
      { pubkey: payeePrivateKey.publicKey, isSigner: false, isWritable: true },
      { pubkey: payerPrivateKey.publicKey, isSigner: true, isWritable: true },
      { pubkey: SystemProgram.programId, isSigner: false, isWritable: true },
    ],
    programId,
    data: Buffer.from(Uint8Array.of(instruction,
      ...new BN(rentAmount).toArray("le", 8),
    ))
  })

  await sendAndConfirmTransaction(
    connection,
    new Transaction().add(transactionInstruction),
    [payerPrivateKey],
  );