Coinbase Ruby SDK

The Coinbase Ruby SDK enables the simple integration of crypto into your app. By calling Coinbase's Platform APIs, the SDK allows you to provision crypto wallets, send crypto into/out of those wallets, track wallet balances, and trade crypto from one asset into another.

The SDK currently supports Customer-custodied Wallets on the Base Sepolia test network.

NOTE: The Coinbase SDK is currently in Alpha. The SDK:

• may make backwards-incompatible changes between releases
• should not be used on Mainnet (i.e. with real funds)

Currently, the SDK is intended for use on testnet for quick bootstrapping of crypto wallets at hackathons, code academies, and other development settings.

Documentation

• Platform API Documentation
• Ruby SDK Documentation

Installation

In Your Ruby Project

Add the following to your Gemfile:

gem 'coinbase-sdk'

Or if you are specifying dependencies in your Gemspec:

Gem::Specification.new do |spec|
  spec.add_runtime_dependency 'coinbase-sdk'
end

Then run:

bundler install

In the Interactive Ruby Shell (irb)

On the command-line, run:

gem install coinbase-sdk

After running irb, require the Gem:

require 'coinbase'

Requirements

• Ruby 2.7+.

Usage

Initialization

To start, create a CDP API Key. Then, initialize the Platform SDK by passing your API Key name and API Key's private key via the configure method:

api_key_name = 'Copy your API Key name here.'
api_key_private_key = 'Copy your API Key\'s private key here.'

Coinbase.configure do |config|
  config.api_key_name = api_key_name
  config.api_key_private_key = api_key_private_key
end

This will allow you to authenticate with the Platform APIs and get access to the default_user.

u = Coinbase.default_user

Wallets, Addresses, and Transfers

Now, create a Wallet from the User. Wallets are created with a single default Address.

# Create a Wallet with one Address by default.
w1 = u.create_wallet

Next, view the default Address of your Wallet. You will need this default Address in order to fund the Wallet for your first Transfer.

# A Wallet has a default Address.
a = w1.default_address
a.to_s

Wallets do not have funds on them to start. In order to fund the Address, you will need to send funds to the Wallet you generated above. If you don't have testnet funds, get funds from a faucet.

# Create a new Wallet to transfer funds to.
# Then, we can transfer 0.00001 ETH out of the Wallet to another Wallet.
w2 = u.create_wallet
w1.transfer(0.00001, :eth, w2).wait!

Re-Instantiating Wallets

The SDK creates Wallets with developer managed keys, which means you are responsible for securely storing the keys required to re-instantiate Wallets. The below code walks you through how to export a Wallets and store it in a secure location.

# Optional: Create a new Wallet if you do not already have one.
# Export the data required to re-instantiate the Wallet.
w3 = u.create_wallet
data = w3.export

In order to persist the data for the Wallet, you will need to implement a store method to store the data export in a secure location. If you do not store the Wallet in a secure location you will lose access to the Wallet and all of the funds on it.

# At this point, you should implement your own "store" method to securely persist
# the data required to re-instantiate the Wallet at a later time.
store(data)

The below code demonstrates how to re-instantiate a Wallet from the data export.

# The Wallet can be re-instantiated using the exported data.
# w2 will be equivalent to w1.
w4 = u.import_wallet(data)

Development

Ruby Version

Developing in this repository requires Ruby >= 2.7.0. To install this on an M2 Mac, run the following command:

RUBY_CFLAGS=-DUSE_FFI_CLOSURE_ALLOC rbenv install 2.7.0

Set-up

Clone the repo by running:

git clone https://github.com/coinbase/coinbase-sdk-ruby.git

To install all dependencies, run:

bundle install

This SDK transitively depends on rbsecp256k1. Follow these instructions to ensure you have the necessary dependencies installed.

The SDK assumes the existence of a BASE_SEPOLIA_RPC_URL environment variable defined in your .env file. By default, this is the publicly available endpoint, which is rate-limited. To provision your own endpoint, go to the CDP Portal. Then copy and paste your Base Sepolia RPC URL in the .env file:

BASE_SEPOLIA_RPC_URL=YOUR-URL

Linting

To autocorrect all lint errors, run:

make format

To detect all lint errors, run:

make lint

Testing

To run all tests, run:

make test

To run a specific test, run (for example):

bundle exec rspec spec/coinbase/wallet_spec.rb

REPL

The repository is equipped with a REPL to allow developers to play with the SDK. To start it, run:

make repl

Generating Documentation

To generate documentation from the Ruby comments, run:

make docs