@launchfort/flock-mongo

Flock Mongo

Flock Mongo is a Flock plugin for Mongodb.

Install

npm install launchfort/flock-mongo

Usage

// .flockrc.js
const { DefaultMigrator, NodeModuleMigrationProvider } = require('@launchfort/flock')
const { DataAccessProvider, TemplateProvider } = require('@launchfort/flock-mongo')

const migrationDir = 'migrations'
const migrationTableName = 'migration'
const dap = new DataAccessProvider({ migrationTableName })
const mp = new NodeModuleMigrationProvider({ migrationDir })

exports.migrator = new DefaultMigrator(mp, dap)
exports.migrationDir = migrationDir
exports.templateProvider = new TemplateProvider()

Migrations

When writing migrations that use flock-mongo the QueryInterface#query method accepts a function that will be called with a Mongo.Db instance.

See: http://mongodb.github.io/node-mongodb-native/3.1/api/Db.html

Example:

exports.up = queryInterface => {
  return queryInterface.query(db => {
    return db.collection('user').find({ age: 1 })
  })
}

The QueryInterface#query method accepts a function with the following signature:

// Function that resolves to a Mongo Cursor instance, a document or an array
// of documents.
(db: Db): Promise<Cursor | {} | {}[]>

The result of running QueryInterface#query will be a Flock.QueryResult where rows will be an array of documents.

Example:

exports.up = async (queryInterface) => {
  const result = await queryInterface.query(db => {
    return db.collection('user').find({ age: 1 })
  })

  // Where result.rowCount is the number or documents returned.
  // And result.rows is an array of documents.
  console.log(result.rows)
}

API

Flock Mongo exports implementations of Flock's DataAccessProvider and TemplateProvider as the DataAccessProvider and TemplateProvider classes.

The DataAccessProvider class will connect to your Mongo DB by reading the connection string from the DATABASE_URL environment variable. Optionally you can override the behaviour by passing in the connectionString option to the constructor.

If the connection string does not contain a database then the admin database will be used.

See: https://docs.mongodb.com/manual/reference/connection-string/

class DataAccessProvider implements Flock.DataAccessProvider {
  constructor ({
    migrationTableName = 'migration',
    connectionString = process.env.DATABASE_URL } = {})
}