Building and Testing TypeORM

This document describes how to set up your development environment and run TypeORM test cases.

See the contribution guidelines if you'd like to contribute to TypeORM.

Prerequisite Software

Before you can build and test TypeORM, you must install and configure the following products on your development machine:

  • Git and/or the GitHub app (for Mac or Windows); GitHub's Guide to Installing Git is a good source of information.

  • Node.js, (better to install latest version) which is used to run a development web server, run tests, and generate distributable files. Depending on your system, you can install Node either from source or as a pre-packaged bundle.

  • Mysql is required to run tests on this platform (or docker)

  • MariaDB is required to run tests on this platform (or docker)

  • Postgres is required to run tests on this platform (or docker)

  • Oracle is required to run tests on this platform

  • Microsoft SQL Server is required to run tests on this platform

  • For MySQL, MariaDB and Postgres you can use docker instead (docker configuration is here)

Getting the Sources

Fork and clone the repository:

  1. Login to your GitHub account or create one by following the instructions given here.

  2. Clone your fork of the TypeORM repository and define an upstream remote pointing back to the TypeORM repository that you forked in the first place.

# Clone your GitHub repository:
git clone<github username>/typeorm.git

# Go to the TypeORM directory:
cd typeorm

# Add the main TypeORM repository as an upstream remote to your repository:
git remote add upstream

Installing NPM Modules

Install all TypeORM dependencies by running this command:

npm install

ORM config

To create an initial ormconfig.json file, run the following command:

cp ormconfig.json.dist ormconfig.json


To build a distribution package of TypeORM run:

npm run package

This command will generate you a distribution package in the build/package directory. You can link (or simply copy/paste) this directory into your project and test TypeORM there (but make sure to keep all node_modules required by TypeORM).

To build the distribution package of TypeORM packed into a .tgz, run:

npm run pack

This command will generate you a distribution package tar in the build directory (build/typeorm-x.x.x.tgz). You can copy this tar into your project and run npm install ./typeorm-x.x.x.tgz to bundle your build of TypeORM in your project.

Running Tests Locally

It would be greatly appreciated if PRs that change code come with appropriate tests.

To create a test for a specific issue opened on github, create a file: test/github-issues/<num>/issue-<num>.ts where <num> is the corresponding github issue. For example, if you were creating a PR to fix github issue #363, you'd create test/github-issues/363/issue-363.ts.

Most tests will benefit from using this template as a starting point:

import "reflect-metadata";
import { createTestingConnections, closeTestingConnections, reloadTestingDatabases } from "../../utils/test-utils";
import { DataSource } from "../../../src/data-source/DataSource"
import { expect } from "chai";

describe("github issues > #<issue number> <issue title>", () => {

    let dataSources: DataSource[];
    before(async () => dataSources = await createTestingConnections({
        entities: [__dirname + "/entity/*{.js,.ts}"],
        schemaCreate: true,
        dropSchema: true,
    beforeEach(() => reloadTestingDatabases(dataSources));
    after(() => closeTestingConnections(dataSources));

    it("should <put a detailed description of what it should do here>", () => Promise.all( dataSource => {

       // tests go here


    // you can add additional tests if needed


If you place entities in ./entity/<entity-name>.ts relative to your issue-<num>.ts file, they will automatically be loaded.

To run the tests, setup your environment configuration by copying ormconfig.json.dist into ormconfig.json and replacing parameters with your own.

Then run tests:

npm test

You should execute test suites before submitting a PR to github. All the tests are executed on our Continuous Integration infrastructure and a PR could only be merged once the tests pass.

Executing only some tests: When you are creating tests to some specific code, you may want only execute the tests that you're creating, so you waste less time to verify your code. To do this, you can temporarily modify your tests definitions adding .only mocha commands (describe, it). Example:

describe.only('your describe test', ....)

Hint: you can use the --grep flag to pass a Regex to gulp-mocha. Only the tests have have describe/it statements that match the Regex will be run. For example:

npm test -- --grep="github issues > #363"

This is useful when trying to get a specific test or subset of tests to pass.

Faster developer cycle for editing code and running tests

The npm test script works by deleting built TypeScript code, rebuilding the codebase, and then running tests. This can take a long time.

Instead, for a quicker feedback cycle, you can run npm run compile -- --watch to make a fresh build and instruct TypeScript to watch for changes and only compile what code you've changed.

Once TypeScript finishes compiling your changes, you can run npm run test-fast (instead of test), to trigger a test without causing a full recompile, which allows you to edit and check your changes much faster.

Using Docker

To run your tests you need dbms installed on your machine. Alternatively, you can use docker with all dbms images inside it. To use dbms for your tests from docker simply run docker-compose up in the root of the project. Once all images are fetched and run you can run tests.

  • The docker image of mssql-server needs at least 3.25GB of RAM.

  • Make sure to assign enough memory to the Docker VM if you're running on Docker for Mac or Windows

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