Properly Convert Lamports to SOL

There is not much that I could find for my particular situation since Solana development is so new, but I was able to resolve it when stumbling upon the parseFloat() method.

I first had to remove the quotient from the const fromAirDropSignature and prepend the parseFloat() method to walletBalanceinside the console.log section.

Intial code:

    const getWalletBalance = async () => {
  try {
    const connection = new Connection(clusterApiUrl("devnet"), "confirmed");
    const walletBalance = await connection.getBalance(publicKey);
    console.log(`Wallet balance is ${walletBalance}`);
  } catch (err) {
    console.error(err);
  }
};
const airDropSol = async () => {
  try {
    const connection = new Connection(clusterApiUrl("devnet"), "confirmed");

    const fromAirDropSignature = await connection.requestAirdrop(
      publicKey,
      (2 * LAMPORTS_PER_SOL) /= LAMPORTS_PER_SOL
    );

Output:

    Wallet balance is 0

Working Code:

const getWalletBalance = async () => {
  try {
    const connection = new Connection(clusterApiUrl("devnet"), "confirmed");
    const walletBalance = await connection.getBalance(publicKey);
    console.log(
      `Wallet balance is ${parseFloat(walletBalance) / LAMPORTS_PER_SOL} SOL`
    );
  } catch (err) {
    console.error(err);
  }
};
const airDropSol = async () => {
  try {
    const connection = new Connection(clusterApiUrl("devnet"), "confirmed");

    const fromAirDropSignature = await connection.requestAirdrop(
      publicKey,
      1.0024 * LAMPORTS_PER_SOL
    );

Output:

Wallet balance is 1.0024 SOL

One thing I notice is that when using 'devnet', it will not allow a denomination higher than 2. Any integer below that will work.

In all libraries, I think that there are auxiliary operations to perform these conversions, in the library Solnet for .Net we do this operation:

decimal ConvertToSol(ulong lamports)
{
  return decimal.Round((decimal)lamports / 1000000000m, 9);
}

If you translate it to JS it will give you the same result and it works for you

So you can convert the walletBalance to Javascript's BigInt, so that you can easily divide by BigInt(LAMPORTS_PER_URL)

const {
        Connection,
        PublicKey,
        clusterApiUrl,
        Keypair,
        LAMPORTS_PER_SOL,
      } = require("@solana/web3.js");
      const wallet = new Keypair();
      const publicKey = new PublicKey(wallet._keypair.publicKey);
      const secretKey = wallet._keypair.secretKey;
      
      const getWalletBalance = async () => {
        try {
          const connection = new Connection(clusterApiUrl("devnet"), "confirmed");
          let walletBalance = await connection.getBalance(publicKey);
          **walletBalance = BigInt(walletBalance) / BigInt(LAMPORTS_PER_SOL)**
          console.log(`Wallet balance is ${walletBalance}`);
        } catch (err) {
          console.error(err);
        }
      };
      const airDropSol = async () => {
        try {
          const connection = new Connection(clusterApiUrl("devnet"), "confirmed");
      
          const fromAirDropSignature = await connection.requestAirdrop(
            publicKey,
            2 * LAMPORTS_PER_SOL
          );
      
          await connection.confirmTransaction(fromAirDropSignature);
        } catch (err) {
          console.log(err);
        }
      };
      const main = async () => {
        await getWalletBalance();
        await airDropSol();
        await getWalletBalance();
      };
      main();

What you are experiencing is due to limitations of airdrop functionality on SOLANA Devnet and Testnet. According to official documentation: "Note that airdrops are only available on Devnet and Testnet. Both are limited to 1 SOL per request."

Reference: https://docs.solana.com/running-validator/validator-start

Interesting fact is that the documentation is inconsistent. Why? Because it states it is limited to 1 SOL, while I'm still able to send 1.9 SOL for example (but not 2 or more).

Example:

const
    {
        Connection,
        PublicKey,
        clusterApiUrl,
        Keypair,
        LAMPORTS_PER_SOL
    } = require("@solana/web3.js")

const wallet = new Keypair()

const publicKey = new PublicKey(wallet._keypair.publicKey)
const secretKey = wallet._keypair.secretKey

const getWalletBalance = async () => {
    try {
        const connection = new Connection(clusterApiUrl('devnet'), 'confirmed')
        const walletBalance = await connection.getBalance(publicKey)
        console.log(`Wallet balance is ${walletBalance / LAMPORTS_PER_SOL} SOL`)
    } catch (err) {
        console.error(err)
    }
}

async function airDropSol(tokenNumber) {
    try {
        const connection = new Connection(clusterApiUrl('devnet'), 'confirmed')
        const fromAirDropSignature = await connection.requestAirdrop(publicKey, tokenNumber * LAMPORTS_PER_SOL)
        await connection.confirmTransaction(fromAirDropSignature)
    } catch (err) {
        console.error(err)
    }
}

const main = async () => {
    await getWalletBalance()
    // argument <= 2.0
    await airDropSol(1.9)
    await getWalletBalance()
}
main()