Show HN: Mongoose unit of work – transactions made easy

6 hours ago 1

A lightweight implementation of the Unit of Work pattern for Mongoose transactions with support for resilient transactions and logging.

npm install mongoose-unit-of-work

import mongoose from "mongoose"; import { UnitOfWork } from "mongoose-unit-of-work"; // Create a unit of work instance const uow = new UnitOfWork(mongoose.connection); // Execute a transaction await uow.executeTransaction(async (session, uow) => { // Perform your database operations here const user = await User.create([{ name: "John" }], { session }); const order = await Order.create([{ userId: user[0]._id }], { session }); return { user, order }; });

For handling transient transaction errors with automatic retries:

import { ResilientUnitOfWork } from "mongoose-unit-of-work"; // Create a resilient unit of work instance with custom retry options const uow = new ResilientUnitOfWork(mongoose.connection, { maxRetries: 3, initialDelayMs: 100, maxDelayMs: 1000, backoffFactor: 2, retryableErrors: [ "TransientTransactionError", "UnknownTransactionCommitResult", ], }); // Execute a transaction with automatic retries await uow.executeTransaction(async (session, uow) => { // Your transaction code here });

Simple transaction management
Automatic session handling
Error handling with automatic rollback
TypeScript support
Built-in logging support
Resilient transactions with configurable retry options
Configurable transaction options (read concern, write concern, read preference)

begin(): Start a new transaction
commit(): Commit the current transaction
abort(): Rollback the current transaction
dispose(): Clean up resources
executeTransaction<T>(fn): Execute a function within a transaction
getSession(): Get the current session
execute<T>(fn): Execute a function within an existing transaction

Extends UnitOfWork with additional features:

Automatic retry on transient transaction errors
Configurable retry options
Exponential backoff strategy

Default Transaction Options

const DEFAULT_SESSION_OPTIONS = { readConcern: "snapshot", writeConcern: { w: "majority", wtimeout: 3000, }, readPreference: "primary", };

const DEFAULT_RETRY_OPTIONS = { maxRetries: 3, initialDelayMs: 100, maxDelayMs: 1000, backoffFactor: 2, retryableErrors: [ "TransientTransactionError", "UnknownTransactionCommitResult", ], };