How to npm install new deps with this great booster?

[johnib]

node-docker-good-defaults/docker-compose.yml

Lines 30 to 34 in 69c923b

	# this is a workaround to prevent host node_modules from accidently getting mounted in container
	# in case you want to use node/npm both outside container for test/lint etc. and also inside container
	# this will overwrite the default node_modules dir in container so it won't conflict with our
	# /opt/node_app/node_modules location. Thanks to PR from @brnluiz
	- notused:/opt/node_app/app/node_modules

[BretFisher]

docker compose run node npm install
Then the volume is seeded, so you can run
docker compose up

[johnib]

I mean during development, sometimes we need to add a new dependency.

All long we did npm install package-name, it would install the package on the host's node_modules and be available for the container process.

Is there as simple as that way to install new deps without stopping the container?

Btw, the perf gain is insane! Thank you 🙏

[BretFisher]

The process depends on your setup. Let's assume you're using the docker-compose.yaml in this example repo:

• Your app is running (It's already been seeded with packages)
• You're using nodemon to auto-restart on changes in the container
• You're bind-mounting in the package.json and package-lock.json from your host

docker compose exec node npm install --save <package name>
# nodemon should see the package.json change and restart node

[johnib]

I'm not sure why would this work? it certainly won't install the package to the ../node_modules folder.
It will use the node_modules folder (which is bound to notused volume) and install all dependencies into it.

[BretFisher]

Right, sorry, I'm getting my examples mixed up (likely because I have 4 repos with various setups for Node.js and this repo is the oldest). I think I've refreshed my memory on how this one works.

There are pro's and con's to each setup. Some setups are simple, but slow. Others are more complex but optimize for npm install speed, etc.

In this repos docker-compose.yml, since we install the node_modules higher in the path, you'd just need to change directory before the install, so revised instructions would be:

docker compose exec node bash
cd ..
npm install --save <package name>
# nodemon should see the package.json change and restart node

Or a one-liner, just change the working dir of the command:
docker compose exec -w /opt/node_app/ node npm install --save <package name>

That installs it in the container read/write layer for that instance and saves it to the package.json for future builds. Does that help?