@teamplay/backend NPM

Teamplay Backend

Create a new ShareDB backend instance

Installation

yarn add @teamplay/backend

Requirements

Configuration

The package can be configured using the following environment variables:

MONGO_URL: Specifies the URL for the MongoDB connection. MongoDB is used as the primary database unless overridden by setting NO_MONGO to true.
NO_MONGO: When set to true, this variable disables the use of MongoDB. In this case, the package will utilize a Mingo database, persisting data to SQLite.
DB_PATH: Defines the file path for the SQLite database. This setting is relevant when NO_MONGO is true. If DB_PATH is not specified, the default file 'sqlite.db' will be used.
DB_LOAD_SNAPSHOT: An optional variable that can be set with a path to a SQLite snapshot file. This setting is relevant when NO_MONGO is true. If provided, the SQLite database will be initialized from this snapshot.
DB_READONLY: Set to true to disable persistence to SQLite.
REDIS_URL: URL for the Redis connection.
NO_REDIS: Set to true to use a mocked Redis client.

Database Initialization

The backend toggles between MongoDB and Mingo for database operations, influenced by environment settings:

MongoDB: Used when MONGO_URL is set and NO_MONGO is false.
Mingo and SQLite: Activated by setting NO_MONGO to true. Mingo handles operations, while SQLite is used solely for data persistence, initialized from DB_PATH if provided.
SQLite Snapshot: When DB_LOAD_SNAPSHOT is set, SQLite is initialized with this pre-populated data snapshot and pulls data to Mingo.

This setup ensures flexibility in database management based on environment configurations. Data persistence can be disabled by setting DB_READONLY to true.

Cloning Existing SQLite Snapshots

In scenarios where there is a need to create new SQLite database snapshots based on existing ones, the combination of DB_LOAD_SNAPSHOT and DB_PATH environment variables can be effectively utilized for cloning. This feature is particularly useful for initializing new environments or testing purposes.

To clone an existing snapshot, set DB_LOAD_SNAPSHOT to the path of the existing snapshot file (e.g., snapshot.db) and specify a new file name in DB_PATH for the cloned database (e.g., clone-snapshot.db).

For example:

NO_MONGO=true DB_LOAD_SNAPSHOT=snapshot.db DB_PATH=clone-snapshot.db startupjs server

Upon server initialization with these settings, the system will clone the data from snapshot.db into a new database file named clone-snapshot.db. Subsequently, the server will continue operations using the new clone-snapshot.db as its database source. This cloning process provides a seamless way to replicate and utilize existing database states in new instances.

Usage

To use the backend package in your StartupJS project, import and initialize it as follows:

import getBackend from '@teamplay/backend'

export default async function runServer () {
  const backend = await getBackend(options)
  // ...
}

where options are:

pollDebounce: the minimum delay between subsequent database polls. It is used individually for each collection in the database. This is used to batch updates and reduce load on the database.