How to use TypeScript & Docker building a REST service with debugging enabled (e.g. WebStorm or VSCode).

# Clone the directory
$ git clone https://github.com/stefanwalther/boilerplate-typescript-rest-docker

# Install the local dependencies
# - Not necessary if you just want to use/test the docker containers

$ npm install

The development environment contains the following:

• A docker container called rest-service containing the REST server as defined in ./src.
• The REST services is exposed at http://localhost:8000.
• Watcher (using nodemonhttp://nodemon.io/ ): As soon as you make changes to the ./src folder, the TypeScript files will be transpiled again and the server restarted.
  • So you can run your integration tests against your local rest-service container, which is after any change immediately up to date.
• Remote debugging enabled through port 5858.

$ docker-compose --f=./docker/docker-compose.dev.yml up

This will give you all of the above described.

Assuming that rest-service itself could rely on other services it makes sense just to spin up the development environment:

$ docker-compose --f=./docker/docker-compose.dev.yml up

So you can run your integration tests against http://localhost8000 The rest-service will be updated every time you make updates to the ./src folder.

If you want to debug the rest-service (e.g. when hitting integration tests against the rest-service) this is the configuration being used in this example:

Create a remote debugger

• ./docker/docker-compose.dev.yml opens the port 5858 for the debugger, so let's connect to it:

Running the unit test in this scenario is straight-forward, just configure WebStorm as follows. (This will not use the container, just directly test the transpiled TypeScript code).

Most of the settings should be default, except:

• Extra mocha options: --require ./test/mocha.conf.js
• Test file patterns: ./test/unit/**/*.spec.ts

If you want to debug the rest-service (running inside the container), follow these steps:

1) Set up the remote debugger as shown above
2) Run the development environment docker-compose --f=./docker/docker-compose.dev.yml up

3) Set up the integration tests in Mocha:

The configuration is very similar to the unit tests:

• Extra mocha options: --require ./test/mocha.conf.js
• Test file patterns: ./test/integration/**/*.spec.ts

4) Start your "Remote Debugger"

Here come the trick. If you don't see your ./*.ts files (as in the screenshot below), then the sourcemaps as created by tsc have not been resolved by WebStorm. (That's a bug and I'll file it as such).

There's a neat trick, though a bit annoying, but i works:

Just press the "Re-Run Debugger" icon, and then you should see the ./*.ts files as in the second following screenshot.

Once this works you can hit any breakpoint in the rest-service (e.g. by running test:integration in Run mode) and it will be hit:

To simulate the Continuous Integration script run the following

$ bash ./docker/docker-ci.sh

An example how to implement CI using travis is provided, have a look at the .travis.yml file and the result .

This solutions is very much inspired by the following two articles:

• https://hharnisc.github.io/2016/06/19/integration-testing-with-docker-compose.html
• https://medium.com/@creynders/debugging-node-apps-in-docker-containers-through-webstorm-ae3f8efe554d#.mplfu74fz

Another very interesting read in that context:

• https://blog.hospodarets.com/nodejs-debugging-in-chrome-devtools