Eth Keyring Controller

A module for managing groups of Ethereum accounts called "Keyrings", defined originally for MetaMask's multiple-account-type feature.

To add new account types to a KeyringController, just make sure it follows The Keyring Class Protocol.

The KeyringController has three main responsibilities:

• Initializing & using (signing with) groups of Ethereum accounts ("keyrings").
• Keeping track of local nicknames for those individual accounts.
• Providing password-encryption persisting & restoring of secret information.

Installation

yarn add eth-keyring-controller

This library uses the Node.js events API. If you are using this library outside of a Node.js context, ensure that you have a polyfill for the events API (this is built-in to browserify).

Usage

const KeyringController = require('eth-keyring-controller');
const SimpleKeyring = require('@metamask/eth-simple-keyring');

const keyringController = new KeyringController({
  keyringTypes: [SimpleKeyring], // optional array of types to support.
  initState: initState.KeyringController, // Last emitted persisted state.
  encryptor: {
    // An optional object for defining encryption schemes:
    // Defaults to Browser-native SubtleCrypto.
    encrypt(password, object) {
      return new Promise('encrypted!');
    },
    decrypt(password, encryptedString) {
      return new Promise({ foo: 'bar' });
    },
  },
});

// The KeyringController is also an event emitter:
this.keyringController.on('newAccount', (address) => {
  console.log(`New account created: ${address}`);
});
this.keyringController.on('removedAccount', handleThat);

Methods

Currently the methods are heavily commented in the source code, so it's the best place to look until we aggregate it here as well.

Contributing

Setup

• Install Node.js version 14
  • If you are using nvm (recommended) running nvm use will automatically choose the right node version for you.
• Install Yarn v3
• Run yarn install to install dependencies and run any required post-install scripts

Testing and Linting

Run yarn test to run the tests once.

Run yarn lint to run the linter, or run yarn lint:fix to run the linter and fix any automatically fixable issues.

Release & Publishing

The project follows the same release process as the other libraries in the MetaMask organization. The GitHub Actions action-create-release-pr and action-publish-release are used to automate the release process; see those repositories for more information about how they work.

1. Choose a release version.

   • The release version should be chosen according to SemVer. Analyze the changes to see whether they include any breaking changes, new features, or deprecations, then choose the appropriate SemVer version. See the SemVer specification for more information.

2. If this release is backporting changes onto a previous release, then ensure there is a major version branch for that version (e.g. 1.x for a v1 backport release).

   • The major version branch should be set to the most recent release with that major version. For example, when backporting a v1.0.2 release, you'd want to ensure there was a 1.x branch that was set to the v1.0.1 tag.

3. Trigger the workflow_dispatch event manually for the Create Release Pull Request action to create the release PR.

   • For a backport release, the base branch should be the major version branch that you ensured existed in step 2. For a normal release, the base branch should be the main branch for that repository (which should be the default value).
   • This should trigger the action-create-release-pr workflow to create the release PR.

4. Update the changelog to move each change entry into the appropriate change category (See here for the full list of change categories, and the correct ordering), and edit them to be more easily understood by users of the package.

   • Generally any changes that don't affect consumers of the package (e.g. lockfile changes or development environment changes) are omitted. Exceptions may be made for changes that might be of interest despite not having an effect upon the published package (e.g. major test improvements, security improvements, improved documentation, etc.).
   • Try to explain each change in terms that users of the package would understand (e.g. avoid referencing internal variables/concepts).
   • Consolidate related changes into one change entry if it makes it easier to explain.
   • Run yarn auto-changelog validate --rc to check that the changelog is correctly formatted.

5. Review and QA the release.

   • If changes are made to the base branch, the release branch will need to be updated with these changes and review/QA will need to restart again. As such, it's probably best to avoid merging other PRs into the base branch while review is underway.

6. Squash & Merge the release.

   • This should trigger the action-publish-release workflow to tag the final release commit and publish the release on GitHub.

7. Publish the release on npm.

   • Wait for the publish-release GitHub Action workflow to finish. This should trigger a second job (publish-npm), which will wait for a run approval by the npm publishers team.
   • Approve the publish-npm job (or ask somebody on the npm publishers team to approve it for you).
   • Once the publish-npm job has finished, check npm to verify that it has been published.