The helpers package contains Solana helper functions, for use in the browser and/or node.js, made by the Solana Foundation Developer Ecosystem team and our friends at Anza, Turbin3, Unboxed Software, and StarAtlas.
Make multiple keypairs at once
Make a token mint with metadata
Create multiple accounts with balances of different tokens in a single step
Resolve a custom error message
Get an airdrop if your balance is below some amount
Get a Solana Explorer link for a transaction, address, or block
Get the logs for a transaction
Get simulated compute units (CUs) for transaction instructions
Get a keypair from a keypair file
Get a keypair from an environment variable
Add a new keypair to an env file
Load or create a keypair and airdrop to it if needed
npm i @solana-developers/helpersPRs are very much welcome! Read the CONTRIBUTING guidelines for the Solana course then send a PR!
Usage:
makeKeypairs(amount);In some situations - like making tests for your onchain programs - you might need to make lots of keypairs at once. You can use makeKeypairs() combined with JS destructuring to quickly create multiple variables with distinct keypairs.
const [sender, recipient] = makeKeypairs(2);The makeTokenMint makes a new token mint. A token mint is effectively the factory that produces token of a particular type. So if you want to make a new token, this is the right function for you!
Unlike older tools, the function uses Token Extensions Metadata and Metadata Pointer to put all metadata into the Mint Account, without needing an external Metadata account. If you don't know what that means, just know that things are simpler than they used to be!
Parameters
connection: Connection.mintAuthority: Keypair of the account that can make new tokens.name: string, name of the token.symbol: string, like a ticker symbol. Usually in all-caps.decimals: number, how many decimal places the new token will have.uri: string, URI to a JSON file containing at minimum a value forimage.additionalMetadata: additional metadata as eitherRecord<string, string>orArray<[string, string]>(optional).updateAuthority: PublicKey (optional) - public key of the account that can update the token.freezeAuthority: PublicKey (optional) - public key of the freeze account, default tonull
const mintAddress = await makeTokenMint(
connection,
mintAuthority,
"Unit test token",
"TEST",
9,
"https://raw.githubusercontent.com/solana-developers/professional-education/main/labs/sample-token-metadata.json",
);Frequently, tests for onchain programs need to make not just users with SOL, but also token mints and give each user some balance of each token. To save this boilerplate, createAccountsMintsAndTokenAccounts() handles making user keypairs, giving them SOL, making mints, creating associated token accounts, and minting tokens directly to the associated token accounts.
Eg, to make two new users, and two tokens:
- the first user with million of the first token, none of the second token, and 1 SOL
- the second user with none of the first token, 1 million of the second token, and 1 SOL
Just run:
const usersMintsAndTokenAccounts = await createAccountsMintsAndTokenAccounts(
[
[1_000_000_000, 0], // User 0 has 1_000_000_000 of token A and 0 of token B
[0, 1_000_000_000], // User 1 has 0 of token A and 1_000_000_000 of token B
],
1 * LAMPORTS_PER_SOL,
connection,
payer,
);The returned usersMintsAndTokenAccounts will be an object of the form:
{
users: <Array<Keypair>>
mints: <Array<Keypair>>,
tokenAccounts: <Array<Array><PublicKey>>>
}
tokenAccounts are indexed by the user, then the mint. Eg, the ATA of user[0] for mint[0] is tokenAccounts[0][0].
Usage:
getCustomErrorMessage(programErrors, errorMessage);Sometimes Solana transactions throw an error with a message like:
failed to send transaction: Transaction simulation failed: Error processing Instruction 0: custom program error: 0x10
Usage:
getCustomErrorMessage();Allows you to turn this message into a more readable message from the custom program, like:
This token mint cannot freeze accounts
Just:
-
Get the errors from the specific program's
error.rsfile - for example, there are the errors for the Token Program -
Save the errors into an array
// Token program errors
// https://github.com/solana-labs/solana-program-library/blob/master/token/program/src/error.rs
const tokenProgramErrors = [
"Lamport balance below rent-exempt threshold",
"Insufficient funds",
"Invalid Mint",
"Account not associated with this Mint",
"Owner does not match",
"Fixed supply",
"Already in use",
"Invalid number of provided signers",
"Invalid number of required signers",
"State is unititialized",
"Instruction does not support native tokens",
"Non-native account can only be closed if its balance is zero",
"Invalid instruction",
"State is invalid for requested operation",
"Operation overflowed",
"Account does not support specified authority type",
"This token mint cannot freeze accounts",
"Account is frozen",
"The provided decimals value different from the Mint decimals",
"Instruction does not support non-native tokens",
];Then run:
const errorMessage = getCustomErrorMessage(
tokenProgramErrors,
"failed to send transaction: Transaction simulation failed: Error processing Instruction 0: custom program error: 0x10",
);And errorMessage will now be:
"This token mint cannot freeze accounts";Usage:
airdropIfRequired(connection, publicKey, lamports, maximumBalance);Request and confirm an airdrop in one step. As soon as the await returns, the airdropped tokens will be ready to use, and the new balance of tokens will be returned. The maximumBalance is used to avoid errors caused by unnecessarily asking for SOL when there's already enough in the account, and makes airdropIfRequired() very handy in scripts that run repeatedly.
To ask for 0.5 SOL, if the balance is below 1 SOL, use:
const newBalance = await airdropIfRequired(
connection,
keypair.publicKey,
0.5 * LAMPORTS_PER_SOL,
1 * LAMPORTS_PER_SOL,
);Usage:
getExplorerLink(type, identifier, clusterName);Get an explorer link for an address, block or transaction (tx works too).
getExplorerLink(
"address",
"dDCQNnDmNbFVi8cQhKAgXhyhXeJ625tvwsunRyRc7c8",
"mainnet-beta",
);Will return "https://explorer.solana.com/address/dDCQNnDmNbFVi8cQhKAgXhyhXeJ625tvwsunRyRc7c8". The cluster name isn't included since mainnet-beta is the default.
getExplorerLink(
"address",
"dDCQNnDmNbFVi8cQhKAgXhyhXeJ625tvwsunRyRc7c8",
"devnet",
);Will return "https://explorer.solana.com/address/dDCQNnDmNbFVi8cQhKAgXhyhXeJ625tvwsunRyRc7c8?cluster=devnet"
getExplorerLink("block", "241889720", "mainnet-beta");Will return "https://explorer.solana.com/block/241889720"
Usage:
confirmTransaction(connection, transaction);Confirm a transaction, and also gets the recent blockhash required to confirm it.
await confirmTransaction(connection, transaction);Usage:
getLogs(connection, transaction);Get the logs for a transaction signature:
const logs = await getLogs(connection, transaction);The logs will be an array of strings, eg:
[
"Program 11111111111111111111111111111111 invoke [1]",
"Program 11111111111111111111111111111111 success",
];This a good way to assert your onchain programs return particular logs during unit tests.
Usage:
getSimulationComputeUnits(connection, instructions, payer, lookupTables);Get the compute units required for an array of instructions. Create your instructions:
const sendSol = SystemProgram.transfer({
fromPubkey: payer.publicKey,
toPubkey: recipient,
lamports: 1_000_000,
});Then use getSimulationComputeUnits to get the number of compute units the instructions will use:
const units = await getSimulationComputeUnits(
connection,
[sendSol],
payer.publicKey,
);You can then use ComputeBudgetProgram.setComputeUnitLimit({ units }) as the first instruction in your transaction. See How to Request Optimal Compute Budget for more information on compute units.
Usage:
getKeypairFromFile(filename);Gets a keypair from a file - the format must be the same as Solana CLI uses, ie, a JSON array of numbers:
To load the default keypair ~/.config/solana/id.json, just run:
const keyPair = await getKeypairFromFile(file);or to load a specific file:
const keyPair = await getKeypairFromFile("somefile.json");or using home dir expansion:
const keyPair = await getKeypairFromFile("~/code/solana/demos/steve.json");Usage:
getKeypairFromEnvironment(environmentVariable);Gets a keypair from a secret key stored in an environment variable. This is typically used to load secret keys from env files.
const keypair = await getKeypairFromEnvironment("SECRET_KEY");Usage:
addKeypairToEnvFile(keypair, environmentVariable, envFileName);Saves a keypair to the environment file.
await addKeypairToEnvFile(testKeypair, "SECRET_KEY");or to specify a file name:
await addKeypairToEnvFile(testKeypair, "SECRET_KEY", ".env.local");This will also reload the env file.
Usage:
initializeKeypair(connection, options);Loads in a keypair from the filesystem, or environment and then airdrops to it if needed.
How the keypair is initialized is dependent on the initializeKeypairOptions:
interface initializeKeypairOptions {
envFileName?: string;
envVariableName?: string;
airdropAmount?: number | null;
minimumBalance?: number;
keypairPath?: string;
}By default, the keypair will be retrieved from the .env file. If a .env file does not exist, this function will create one with a new keypair under the optional envVariableName.
To load the keypair from the filesystem, pass in the keypairPath. When set, loading a keypair from the filesystem will take precedence over loading from the .env file.
If airdropAmount amount is set to something other than null or 0, this function will then check the account's balance. If the balance is below the minimumBalance, it will airdrop the account airdropAmount.
To initialize a keypair from the .env file, and airdrop it 1 sol if it's beneath 0.5 sol:
const keypair = await initializeKeypair(connection);To initialize a keypair from the .env file under a different variable name:
const keypair = await initializeKeypair(connection, {
envVariableName: "TEST_KEYPAIR",
});To initialize a keypair from the filesystem, and airdrop it 3 sol:
const keypair = await initializeKeypair(connection, {
keypairPath: "~/.config/solana/id.json",
airdropAmount: LAMPORTS_PER_SOL * 3,
});The default options are as follows:
const DEFAULT_AIRDROP_AMOUNT = 1 * LAMPORTS_PER_SOL;
const DEFAULT_MINIMUM_BALANCE = 0.5 * LAMPORTS_PER_SOL;
const DEFAULT_ENV_KEYPAIR_VARIABLE_NAME = "PRIVATE_KEY";Secret keys can be read in either the more compact base58 format (base58.encode(randomKeypair.secretKey);), like:
# A random secret key for demo purposes
SECRET_KEY=QqKYBnj5mcgUsS4vrCeyMczbTyV1SMrr7SjSAPj7JGFtxfrgD8AWU8NciwHNCbmkscbvj4HdeEen42GDBSHCj1NOr the longer, 'array of numbers' format JSON.stringify(Object.values(randomKeypair.secretKey));:
# A random secret key for demo purposes
SECRET_KEY=[112,222,91,246,55,109,221,4,23,148,251,127,212,180,44,249,182,139,18,13,209,208,6,7,193,210,186,249,148,237,237,1,70,118,1,153,238,134,239,75,187,96,101,138,147,130,181,71,22,82,44,217,194,122,59,208,134,119,98,53,136,108,44,105]We always save keys using the 'array of numbers' format, since most other Solana apps (like the CLI SDK and Rust tools) use the 'array of numbers' format.
To run tests, open a terminal tab, and run:
solana-test-validatorThen in a different tab, run:
npm run testThe tests use the node native test runner.
If you'd like to run a single test, use:
esrun --node-test-name-pattern="getCustomErrorMessage" src/index.test.tsTo just run tests matching the name getCustomErrorMessage.