---
title: Run Node.js tests in a container
linkTitle: Run your tests
weight: 30
keywords: node.js, node, test
description: Learn how to run your Node.js tests in a container.
aliases:
  - /language/nodejs/run-tests/
  - /guides/language/nodejs/run-tests/
---

## Prerequisites

Complete all the previous sections of this guide, starting with [Containerize a Node.js application](containerize.md).

## Overview

Testing is an essential part of modern software development. Testing can mean a
lot of things to different development teams. There are unit tests, integration
tests and end-to-end testing. In this guide you take a look at running your unit
tests in Docker when developing and when building.

## Run tests when developing locally

The sample application already has the Jest package for running tests and has tests inside the `spec` directory. When developing locally, you can use Compose to run your tests.

Run the following command to run the test script from the `package.json` file inside a container.

```console
$ docker compose run server npm run test
```

To learn more about the command, see [docker compose run](/reference/cli/docker/compose/run/).

You should see output like the following.

```console
> docker-nodejs@1.0.0 test
> jest

 PASS  spec/routes/deleteItem.spec.js
 PASS  spec/routes/getItems.spec.js
 PASS  spec/routes/addItem.spec.js
 PASS  spec/routes/updateItem.spec.js
 PASS  spec/persistence/sqlite.spec.js
  ● Console

    console.log
      Using sqlite database at /tmp/todo.db

      at Database.log (src/persistence/sqlite.js:18:25)

    console.log
      Using sqlite database at /tmp/todo.db

      at Database.log (src/persistence/sqlite.js:18:25)

    console.log
      Using sqlite database at /tmp/todo.db

      at Database.log (src/persistence/sqlite.js:18:25)

    console.log
      Using sqlite database at /tmp/todo.db

      at Database.log (src/persistence/sqlite.js:18:25)

    console.log
      Using sqlite database at /tmp/todo.db

      at Database.log (src/persistence/sqlite.js:18:25)


Test Suites: 5 passed, 5 total
Tests:       9 passed, 9 total
Snapshots:   0 total
Time:        2.008 s
Ran all test suites.
```

## Run tests when building

To run your tests when building, you need to update your Dockerfile to add a new test stage.

The following is the updated Dockerfile.

```dockerfile {hl_lines="27-35"}
# syntax=docker/dockerfile:1

ARG NODE_VERSION=18.0.0

FROM node:${NODE_VERSION}-alpine as base
WORKDIR /usr/src/app
EXPOSE 3000

FROM base as dev
RUN --mount=type=bind,source=package.json,target=package.json \