DB Fabricator

Convenient way to populate your database, mainly for setting up e2e/integration testing data.

Install

$ npm install db-fabricator

Usage

Setup

import { Fabricator, MySQLAdaptor } from 'db-fabricator';
import * as mysql from 'mysql';

let conn = mysql.createConnection({
  host: 'localhost',
  user: 'dev',
  password: 'pass',
  database: 'dbname'
});

Fabricator.setAdaptor(new MySQLAdaptor({conn: conn}));

Defining Template

Define template for each of the data type (table if you are using relational DB). The base template name has to be the table name.

 
Fabricator.template({
  name: 'organization',
  attr: {
    name: 'Fabricator Inc'
  }
});
Fabricator.template({
  name: 'department',
  attr: {
    name: 'IT',
    organizationId: () => Fabricator.fabricate('organization').then(org => org.id)
  }
});
Fabricator.template({
  name: 'user',
  attr: {
    firstName: 'Bob',
    lastName: 'Smith',
    username: (obj) => `${obj.firstName}.${obj.lastName}`,
    departmentId: () => Fabricator.fabricate('department').then(dept => dept.id)
  }
});

Define template from another template

You can define template from another template by specifying from property with another template name.

Fabricator.template({
  name: 'user-teacher',
  from: 'user',
  attr: {
    type: 'teacher'
  }
});
Fabricator.template({
  name: 'user-student',
  from: 'user',
  attr: {
    type: 'student'
  }
});
Fabricator.template({
  name: 'user-student-with-email',
  from: 'user-student',
  attr: {
    email: (obj) => `${obj.username}@student.school.edu`,
  }
});

Populate data from template

Conveniently populate data from the template. You can still override any attribute from the template.

Fabricator.fabricate('user', { firstName: 'Bob' }); // Department and organization will be automatically created for the user
Fabricator.fabricate('user', { firstName: 'Jon' }); // Jon will have different department and organization
Fabricator.fabricate('user-student-with-email', { firstName: 'Dan' });

If you want to use the same department/organization for some users:

let fabId = Fabricator.getId;
let org            = Fabricator.fabricate('organization');
let dept_it        = Fabricator.fabricate('department', { name: 'IT',        organizationId: fabId(org) });
let dept_marketing = Fabricator.fabricate('department', { name: 'Marketing', organizationId: fabId(org) });
let user_bob       = Fabricator.fabricate('user', { firstName: 'Bob',  departmentId: fabId(dept_it) });
let user_jane      = Fabricator.fabricate('user', { firstName: 'Jane', departmentId: fabId(dept_it) });
let user_jon       = Fabricator.fabricate('user', { firstName: 'Jon',  departmentId: fabId(dept_marketing) });
let user_mary      = Fabricator.fabricate('user', { firstName: 'Mary', departmentId: fabId(dept_marketing) });

Fabricator.getId is a helper function which will return the id of the resolved promise. It can be passed a promise or just the object from which you want to get the id.

// In the above example
fabId(org)

// is the same as
org.then(o => o.id)

After Create hook

Fabricator.template({
  name: 'organization',
  attr: {
    name: 'Fabricator Inc'
  },
  afterCreate: (org) => {
    let promises: any[] = [];
    promises.push(Fabricator.fabricate('department', { organizationId: org.id }));
    return Promise.all(promises).then((departments) => {
      org.departments = departments;
      return org;
    });
  }
});
 
Fabricator.fabricate('organization').then(org => {
  expect(org.departments.length).to.equal(1);
  expect(org.departments[0].organizationId).to.equal(org.id);
});

Extensible

Currently db-fabricator only supports MySQL data store, but you can create an adaptor for any database. Just implement a class that implements the DataStoreAdaptor interface. For an example, see the MySQLAdaptor implementation.

export interface DataStoreAdaptor {
  createData(tableName: string, finalAttr: Object): Promise<any>;
}

Contributing Guide

Build

$ tsc

Running Test

Install ts-node to run the test without compiling to js first.

$ npm install -g ts-node

Run all tests

$ mocha --compilers ts:ts-node/register test/*

Run the main test

$ mocha --compilers ts:ts-node/register test/fabricator.spec.ts

Run the mysql-adaptor test

$ mocha --compilers ts:ts-node/register test/fabricator-mysql.spec.ts

You have to have a mysql instance running and a user that can create/drop database.

License

MIT