Transaction Extension ​

The transaction extension adds the ability to rollback a set of mutations in the event of an error.

Getting Started ​

Follow the steps below to get started using the transaction extension.

Installation ​

Before installing this extension make sure you have installed harlem.

yarn add @harlem/extension-transaction
# or
npm install @harlem/extension-transaction

Registration ​

To get started simply register this extension with the store you wish to extend.

import transactionExtension from '@harlem/extension-transaction';

import {
    createStore
} from 'harlem';

const STATE = {
    firstName: 'Jane',
    lastName: 'Smith'
};

const {
    state,
    getter,
    mutation,
    transaction,
    onBeforeTransaction,
    onAfterTransaction,
    onTransactionSuccess,
    onTransactionError,
} = createStore('example', STATE, {
    extensions: [
        transactionExtension()
    ]
});

The transaction extension adds several new methods to the store instance (highlighted above).

Usage ​

Defining a transaction ​

A transaction can be defined the same way you define any other core functionality (eg. getter, mutation etc.).

export default transaction('my-transaction', (payload, mutate) => {
    /*
    Any mutations run during this method
    will be rolled back if an error occurs
    */
});