web3

Ethereum JSON-RPC multi-transport client. Rust implementation of Web3.js library.

Documentation: crates.io

Status

Note this package is barely maintained and I am looking for an active maintainer (see #664). If you are starting a new project, I'd recommend choosing https://github.com/gakonst/ethers-rs instead.

Usage

First, add this to your Cargo.toml:

[dependencies]
web3 = "0.19.0"

Example

#[tokio::main]
async fn main() -> web3::Result<()> {
    let transport = web3::transports::Http::new("http://localhost:8545")?;
    let web3 = web3::Web3::new(transport);

    println!("Calling accounts.");
    let mut accounts = web3.eth().accounts().await?;
    println!("Accounts: {:?}", accounts);
    accounts.push("00a329c0648769a73afac7f9381e08fb43dbea72".parse().unwrap());

    println!("Calling balance.");
    for account in accounts {
        let balance = web3.eth().balance(account, None).await?;
        println!("Balance of {:?}: {}", account, balance);
    }

    Ok(())
}

If you want to deploy smart contracts you have written you can do something like this (make sure you have the solidity compiler installed):

solc -o build --bin --abi contracts/*.sol

The solidity compiler is generating the binary and abi code for the smart contracts in a directory called contracts and is being output to a directory called build.

For more see examples folder.

Futures migration

[ ] Get rid of parking_lot (replace with async-aware locks if really needed).
[ ] Consider getting rid of Unpin requirements. (#361)
[x] WebSockets: TLS support (#360)
[ ] WebSockets: Reconnecting & Pings
[x] Consider using tokio instead of async-std for ws.rs transport (issue with test).
[x] Restore IPC Transport

General

[ ] More flexible API (accept Into<X>)
[x] Contract calls (ABI encoding; debris/ethabi)
[X] Batch Requests

Transports

[x] HTTP transport
[x] IPC transport
[x] WebSockets transport

Types

[x] Types for U256,H256,Address(H160)
[x] Index type (numeric, encoded to hex)
[x] Transaction type (Transaction from Parity)
[x] Transaction receipt type (TransactionReceipt from Parity)
[x] Block type (RichBlock from Parity)
[x] Work type (Work from Parity)
[X] Syncing type (SyncStats from Parity)

APIs

[x] Eth: eth_*
[x] Eth filters: eth_*
[x] Eth pubsub: eth_*
[x] net_*
[x] web3_*
[x] personal_*
[ ] traces_*

Parity-specific APIs

[ ] Parity read-only: parity_*
[ ] Parity accounts: parity_* (partially implemented)
[x] Parity set: parity_*
[ ] signer_*

[x] Own APIs (Extendable)

let web3 = Web3::new(transport);
web3.api::<CustomNamespace>().custom_method().wait().unwrap()

Installation on Windows

Currently, Windows does not support IPC, which is enabled in the library by default. To compile, you need to disable the IPC feature:

web3 = { version = "_", default-features = false, features = ["http"] }

Avoiding OpenSSL dependency

On Linux, native-tls is implemented using OpenSSL. To avoid that dependency for HTTPS or WSS use the corresponding features.

web3 = { version = "_", default-features = false, features = ["http-rustls-tls", "ws-rustls-tokio"] }

Note: To fully replicate the default features also add signing & ipc-tokio features.

Cargo Features

The library supports following features:

http - Enables HTTP transport (requires tokio runtime, because of hyper).
http-tls - Enables TLS support via reqwest/default-tls for HTTP transport (implies http; default).
http-native-tls - Enables TLS support via reqwest/native-tls for HTTP transport (implies http).
http-rustls-tls - Enables TLS support via reqwest/rustls-tls for HTTP transport (implies http).
ws-tokio - Enables WS transport using tokio runtime.
ws-tls-tokio - Enables TLS support for WS transport (implies ws-tokio; default).
ws-rustls-tokio - Enables rustls TLS support for WS transport (implies ws-tokio).
ws-async-std - Enables WS transport using async-std runtime.
ws-tls-async-std - Enables TLS support for WS transport (implies ws-async-std).
ipc-tokio - Enables IPC transport using tokio runtime (default).
signing - Enable account namespace and local-signing support (default).
eip-1193 - Enable EIP-1193 support.
wasm - Compile for WASM (make sure to disable default features).
arbitrary_precision - Enable arbitrary_precision in serde_json.
allow-missing-fields - Some response fields are mandatory in Ethereum but not present in EVM-compatible chains such as Celo and Fantom. This feature enables compatibility by setting a default value on those fields.

tomusdrw / rust-web3

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