# zksync-web3-rs

## Table of Contents

- [zksync-web3-rs](#zksync-web3-rs)
  - [Table of Contents](#table-of-contents)
  - [Getting Started with zkSync Web3 SDK](#getting-started-with-zksync-web3-sdk)
    - [Prerequisites](#prerequisites)
    - [Adding dependencies](#adding-dependencies)
    - [First steps](#first-steps)
      - [Importing dependencies](#importing-dependencies)
      - [Connecting to the zkSync Network](#connecting-to-the-zksync-network)
      - [Creating a ZK-Wallet](#creating-a-zk-wallet)
      - [Creating a Payment Transaction](#creating-a-payment-transaction)
      - [Sending the Transaction](#sending-the-transaction)
      - [Checking zkSync account balance](#checking-zksync-account-balance)
    - [Simple Transfer Example](#simple-transfer-example)
      - [Clone the Repository](#clone-the-repository)
      - [Run a zkSync localnet](#run-a-zksync-localnet)
      - [Run the Simple Transfer Example](#run-the-simple-transfer-example)
    - [Conclusion](#conclusion)

## Getting Started with zkSync Web3 SDK

While most of the existing SDKs should work out of the box, deploying smart contracts or using unique zkSync features, like account abstraction, requires providing additional fields to those that Ethereum transactions have by default.

To provide easy access to all of the features of zkSync Era, the `zksync-web3-rs` Rust SDK was created, which is made in a way that has an interface very similar to those of [ethers](https://docs.ethers.io/v5/). In fact, ethers is a peer dependency of our library and most of the objects exported by `zksync-web3-rs` (e.g. `Provider` etc.) inherit from the corresponding `ethers` objects and override only the fields that need to be changed.

The library is made in such a way that after replacing `ethers` with `zksync-web3-rs` most client apps will work out of box.

### Prerequisites

Before you begin, make sure you have the following prerequisites:

- Rust: Ensure that Rust is installed on your system. You can install Rust by following the instructions at [https://www.rust-lang.org/tools/install](https://www.rust-lang.org/tools/install).

- Git: Install Git on your system if you haven't already. You can find installation instructions at [https://git-scm.com/book/en/v2/Getting-Started-Installing-Git](https://git-scm.com/book/en/v2/Getting-Started-Installing-Git).

### Adding dependencies

This crate is published on crates.io, so you can simply do:

```bash
cargo add zksync-web3-rs
```

Or, if you want to use the latest changes, add this to your `Cargo.toml` file:

```bash
zksync-web3-rs = { git = "https://www.github.com/lambdaclass/zksync-web3-rs", branch = "main"}
```

> Maybe consider adding tokio as dependency since we are using a lot of async/await functions. If this example is meant to be done in the main function the #[tokio::main] annotation is needed.

### First steps

In the following steps, we will show you how to create a payment transaction using the `zksync-web3-rs` library.

#### Importing dependencies

Import the `zksync-web3-rs` library into your project by adding the following line to the top of your `main.rs` file:

```rust
use zksync_web3_rs as zksync;
```

#### Connecting to the zkSync Network

To connect to the zkSync network, you need to provide the URL of the zkSync node. The localnet runs both an *Ethereum* node (L1) on port `8545` and an *Era* node (L2) on port `3050`. You can connect to the zkSync Era network using the following code:

```rust
use zksync_web3_rs as zksync;
let provider = zksync::prelude::Provider::try_from("http://localhost:3050").unwrap();
```

#### Creating a ZK-Wallet


> We set the chain id to 270 because we are using the zkSync Era node. If you want to use the mainnet, you should set the chain id to 9.
> https://era.zksync.io/docs/tools/hardhat/testing.html#connect-wallet-to-local-nodes

```rust
use zksync_web3_rs as zksync;
use zksync::signers::{Wallet, Signer};
use zksync::core::k256::ecdsa::SigningKey;
let provider = zksync_web3_rs::prelude::Provider::try_from("http://localhost:3050").unwrap();
let private_key: Wallet<SigningKey> = "0x7726827caac94a7f9e1b160f7ea819f172f7b6f9d2a97f992c38edeab82d4110".parse().unwrap();
let zksync_era_chain_id: u64 = 270;
let wallet = Wallet::with_chain_id(private_key, zksync_era_chain_id);
let zk_wallet = zksync::ZKSWallet::new(wallet, None, Some(provider.clone()), None).unwrap();
```

#### Creating a Payment Transaction
To create a payment transaction, you need to provide the sender's address, the receiver's address, and the amount to transfer. You can create a payment transaction using the following code:
Notice the await, this code should run inside an async function.
```rust,no_run
use zksync_web3_rs as zksync;
use zksync::types::Address;
// Use actual addresses here
let receiver_address: Address = "..".parse().unwrap();
let sender_address: Address = "..".parse().unwrap();
let amount_to_transfer = zksync_web3_rs::types::U256::from(1);
let payment_request = zksync::zks_wallet::TransferRequest::new(amount_to_transfer)
        .to(receiver_address)
        .from(sender_address); // Use zk_wallet.l2_address() method to send it from the wallet  address.
```

#### Sending the Transaction

To send the payment transaction, you need to use the wallet and the transfer request. You can send the transaction using the following code:

> In case you are wondering, the transaction is signed in the `send_transaction` method inside the transfer process.

```rust,compile_fail
let payment_transaction_id =
        zk_wallet.transfer(&payment_request, None).await.unwrap();
```

This will send the transaction to the node and return its ID (hash). To get more information about the transaction we can ask for the `TransactionReceipt` with the following lines:

```rust,compile_fail
use zksync_web3_rs as zksync;
use zksync::prelude::Middleware;
// Using the local node, keep in mind 
// this should be in an async block.
let provider = zksync::prelude::Provider::try_from("http://localhost:3050").unwrap();
let payment_transaction_receipt = provider
        .get_transaction_receipt(payment_transaction_id)
        .await
        .unwrap()
        .unwrap();
```

#### Checking zkSync account balance
```rust,compile_fail
let sender_balance = provider
    .get_balance(sender_address, None)
    .await
    .unwrap();
```

### Simple Transfer Example

There's an executable example involving the previous steps in the `examples` folder. To run the example, follow the steps below:

#### Clone the Repository

To get started, clone the `zksync-web3-rs` repository from GitHub. Open a terminal or command prompt and execute the following commands:

```bash
git clone https://github.com/lambdaclass/zksync-web3-rs.git
cd zksync-web3-rs
```

#### Run a zkSync localnet

To run the zkSync localnet, clone the `local-setup` repository and execute the following command:

```bash
git clone https://github.com/lambdaclass/local-setup
cd local-setup
docker-compose up
```

#### Run the Simple Transfer Example

To run the payment transaction example using EIP1559 transactions on zkSync Era, run the following command:

```bash
cargo run --example simple_payment -- --host <HOST> --port <PORT> --amount <AMOUNT> --from <SENDER_ADDRESS> --to <RECEIVER_ADDRESS> --private-key <PRIVATE_KEY>
```

- `HOST`: The IP address or hostname of the node.
- `PORT`: The port number of the node.
- `AMOUNT`: The amount to transfer.
- `SENDER_ADDRESS`: The address of the sender's Ethereum account, represented in hexadecimal format with the `0x` prefix. For example, `0x123abc...`.
- `RECEIVER_ADDRESS`: The address of the receiver's Ethereum account, represented in hexadecimal format with the `0x` prefix. For example, `0x456def...`.
- `PRIVATE_KEY`: The private key of an Ethereum account with sufficient funds to perform the transaction, represented in hexadecimal format with the `0x` prefix.
- `NETWORK`: The network you want to connect to. There are two options: `era` which will connect to the L2 node and `eth` which will connect to the L1 node.

This command executes the `simple_payment` binary using the provided Makefile.

### Conclusion

Congratulations! You have successfully completed the "Getting Started" guide for the `zksync-web3-rs` SDK. You have learned how to send a simple payment transaction example using EIP1559 transactions on zkSync Era.

By exploring the example code and the repository's documentation, you can further enhance your understanding of interacting with zkSync Era's testnet using the `zksync-web3-rs` SDK.

Feel free to experiment with different configurations and explore other functionalities provided by the SDK.

If you have any questions or need further assistance, don't hesitate to reach out to the repository's community or maintainers.

Happy coding!