web3swift

web3swift is your toolbelt for any kind interactions with Ethereum network.

Ready Features
Design Decisions
Requirements
Migration Guides
Communication
Installation
- CocoaPods
- Carthage
Example Project
Popular questions
What's next
Credits
- Security Disclosure
Donations
License

Usage Doc
- Account Management
- Transactions Operations
  - Prepare Transaction
  - Send Transaction
- Chain State
  - Get Block Number

Ready Features

Design Decisions

Not every JSON RPC function is exposed yet, and priority is given to the ones required for mobile devices
Functionality was focused on serializing and signing transactions locally on the device to send raw transactions to Ethereum network
Requirements for password input on every transaction are indeed a design decision. Interface designers can save user passwords with the user's consent
Public function for private key export is exposed for user convenience but marked as UNSAFE_ :) Normal workflow takes care of EIP155 compatibility and proper clearing of private key data from memory

Requirements

iOS 9.0+ / macOS 10.11+
Xcode 9.0+
Swift 4.1+

Migration Guides

web3swift 2.0 Migration Guide

Communication

When using this lib, please make references to this repo and give your start! :) Nothing makes developers happier than seeing someone else use our work and go wild with it.

If you are using web3swift in your app or know of an app that uses it, please add it to this list.

If you need help, use Stack Overflow and tag web3swift.
If you need to find or understand an API, check our documentation.
If you'd like to see web3swift best practices, check Apps using this library.
If you found a bug, open an issue.
If you have a feature request, open an issue.
If you want to contribute, submit a pull request.

Installation

CocoaPods

CocoaPods is a dependency manager for Cocoa projects. You can install it with the following command:

$ sudo gem install cocoapods

To integrate web3swift into your Xcode project using CocoaPods, specify it in your Podfile:

source 'https://github.com/CocoaPods/Specs.git'
platform :ios, '9.0'

target '<Your Target Name>' do
    use_frameworks!
    pod 'web3swift'
end

Then, run the following command:

$ pod install

Carthage

Carthage is a decentralized dependency manager that builds your dependencies and provides you with binary frameworks.

You can install Carthage with Homebrew using the following command:

$ brew update
$ brew install carthage

To integrate web3swift into your Xcode project using Carthage, specify it in your Cartfile:

github "matterinc/web3swift" "carthage"

Run carthage update to build the framework and drag the built web3swift.framework into your Xcode project.

Example Project

You can try lib by running the example project:

Clone the repo: git clone https://github.com/matterinc/web3swift.git
Move to the repo: cd web3swift/Example/web3swiftExample
Install Dependencies: pod install
Open: open ./web3swiftExample.xcworkspace

Popular questions

Is it possible to get Mnemonic Phrase (Seed Phrase) from Private key using web3swift?

In web3swift there is no backward conversion from Private key to Mnemonic Phrase. Also it is theoretically impossible to recover a phrase from a Private key. After Seed Phrase is converted to some initial entropy the “master key is derived” and the initial entropy is discarded.

The simplest solution is to encrypt the phrase using users pincode and save it in some other secure keystore. Mnemonic Phrase is very sensitive data and you must be very careful to let the user get it. Our advise if you want to show it to user - ask to save a Passphrase when creating BIP32Keystore.

How to interact with custom smart-contract with web3swift?

For example: you want to interact with smart-contract and all you know is - its address (address example: 0xfa28eC7198028438514b49a3CF353BcA5541ce1d).

You can get the ABI of your contract directly from Remix IDE (Solution)

Then you should use contract address and ABI in creating contract object. In example we use Infura Mainnet:

let yourContractABI: String = <CONTRACT JSON ABI>
let toEthereumAddress: EthereumAddress? = <DESTINATION ETHEREUM ADDRESS>
let abiVersion: Int = <ABI VERSION NUMBER>

let contract = Web3.InfuraMainnetWeb3().contract(yourContractABI, at: toEthereumAddress, abiVersion: abiVersion)

Here is the example how you should call some contract method:

let method: String = <CONTRACT METHOD NAME>
let parameters: [AnyObject] = <PARAMETERS>
let extraData: Data = <DATA>
let transactionOptions: TransactionOptions = <OPTIONS>

let transaction = contract.read(method, parameters: parameters, extraData: extraData, transactionOptions: transactionOptions)

Here is the example how you should send transaction to some contract method:

let method: String = <CONTRACT METHOD NAME>
let parameters: [AnyObject] = <PARAMETERS>
let extraData: Data = <DATA>
let transactionOptions: TransactionOptions = <OPTIONS>

let transaction = contract.write(method, parameters: parameters, extraData: extraData, transactionOptions: transactionOptions)

How to set test local node?

You can write something like that:

func setLocalNode(port: Int = 8545) -> Web3? {
    guard let web3 = Web3(url: URL(string: "http://127.0.0.1:\(port)")!) else { return nil }
    return web3
}

What's next

R-Token (Smart Contracts for applying regulatory compliance to tokenized securities issuance and trading)
SRC-20 (Swarm protocol that enables the tokenization of assets on the blockchain - Security Tokens)
ST-20 (ST-20 token is an Ethereum-based token implemented on top of the ERC-20 protocol that adds the ability for tokens to control transfers based on specific rules)
[Objective-C] - a proxy bridge to build your DApp on Objective-C using web3swift
[Performance Improvements]
[More convenient methods for basic namespaces]
Complete Documentation

Credits

Alex Vlasov, @shamatar, alex.m.vlasov@gmail.com

Petr Korolev, @skywinder

Security Disclosure

If you believe you have identified a security vulnerability with web3swift, you should report it as soon as possible via email to Alex Vlasov alex.m.vlasov@gmail.com. Please do not post it to a public issue tracker.

Donations

The Matters are charged with open-sourсe and do not require money for using their web3swift lib. We want to continue to do everything we can to move the needle forward. If you use any of our libraries for work, see if your employers would be interested in donating. Any amount you can donate today to help us reach our goal would be greatly appreciated.

Our Ether wallet address: 0xe22b8979739d724343bd002f9f432f5990879901

License

web3swift is available under the Apache License 2.0 license. See the LICENSE for details.

dexon-foundation/web3swift