repository·develop·Indexed 22 days ago
https://github.com/starknet-io/starknet.jsA JavaScript library for interacting with the Starknet blockchain. It provides tools for building applications, interacting with smart contracts, and managing Starknet-related logic in JavaScript/TypeScript environments. The library includes utilities for calldata compilation, handling Cairo types (such as felt252, u256, and ByteArray), and managing Cairo enums like Option and Result.
Outside Execution, also known as meta-transactions, allows a protocol to submit transactions on behalf of a user account using their signatures. This follows the SNIP-9 standard.
Key Benefits:
A WalletAccount instance is highly versatile and can be used in three primary ways:
Account instance.RpcProvider interface. You can call provider methods (e.g., getBlockNumber()) directly on it. It uses the RPC node URL provided during instantiation.Contract constructor, the WalletAccount acts as both the provider (for read actions) and the signer (for write actions).Recommendation: When the network or account address changes, it is strongly recommended to create a new WalletAccount instance to avoid unexpected behavior between reads and writes.
The RpcProvider class is the primary object used to connect your DApp to the Starknet blockchain. To use it, you must define the network (Mainnet, Sepolia Testnet, Devnet, etc.) and select a node (an RPC provider like Alchemy, Zan, or Infura, or your own local node like Pathfinder or Juno).
Starknet.js communicates with nodes using the RPC specification. It is critical to ensure your Starknet.js version aligns with the RPC version supported by your chosen node.
import { RpcProvider } from 'starknet';The documentation is organized into several locations:
/www/docs. API documentation is in /www/docs/API and guides are in /www/docs/guides./www/versioned_docs.Note on API Docs: API documentation is automatically generated from JSDoc comments in the source code via CI. Do not include changes to /www/docs/API in Pull Requests. Guides in /www/docs/guides must be updated manually in Pull Requests.
The structure of the data returned by a contract call depends on whether the contract was written in Cairo 0 or Cairo 1:
You can detect the contract version using myContract.isCairo1() or check an ABI using cairo.isCairo1Abi(myAbi).
RpcProvider (aliased as Provider for backward compatibility) is used to interact with the Starknet network for read-only operations. It allows you to query the blockchain without signing transactions or messages.In Starknet, there are no Externally Owned Accounts (EOA). All accounts are smart contracts. Because account contracts require a fee to be deployed, the creation process follows a specific lifecycle:
STRK20 is a note-based privacy pool for ERC-20 assets. A DAPP describes desired operations using an array of STRK20_ACTION objects.
| Action | type | Fields | Effect |
|---|---|---|---|
| Deposit | "deposit" | token, amount | Public funds $\rightarrow$ pool (always to self). |
| Withdraw | "withdraw" | token, amount, recipient | Pool $\rightarrow$ public recipient address. |
| Transfer | "transfer" | token, amount (FELT or "OPEN"), recipient | Private transfer inside the pool to another registered user. |
| Invoke | "invoke" | contract, calldata | Calls an invoke helper contract, executed by the pool. |
| Sub-account invoke | "subaccount_invoke" | dapp_name, nonce, calls, collect_policy | Calls contracts through the user's sub-account for this DAPP. |
Note on amount: "OPEN": This is used in multi-action transactions to create an empty note whose value is unknown at build time (e.g., an AMM swap output) and is filled later in the same transaction by a paired invoke or subaccount_invoke action.
The Contract class manages interactions with a specific smart contract using its ABI. It handles:
call and invoke requests to Starknet.Uint256 to BigNumber).JSON.parse.The starknet.js SDK follows a layered architecture for interacting with the network:
Account: The top layer used for signing and submitting transactions.RpcProvider: Wraps the account layer to parse responses and handle retries.RpcChannel: The bottom layer that handles raw JSON-RPC communication.When building applications, you typically interact with Account and Contract objects which rely on an underlying RpcProvider.
When working with typed contracts in Starknet.js, follow these best practices:
typedv2(): Always use the .typedv2() method for the latest and most robust type-checking features..ts ABI files in a dedicated directory.Signer class provides the capability to sign transactions and messages, and allows you to retrieve the associated public key.