Understanding mutagen and upload_dirs

[hirasso]

Hi!

I am using ddev/ddev-pnpm in my ddev projects. I read on the command line that I should exclude node_modules from mutagen by adding it to upload_dirs.

I have these (relevant) settings in my ./ddev/config.yaml:

docroot: public
upload_dirs:
  - content/uploads # my uploads folder (customized bedrock project)
  - ../node_modules # my node_modules folder

The relevant parts of my project's directory structure:

❯ tree -L 2
.
├── node_modules
│   ├── ...
├── public
│   ├── content
├── rector.php
└── vite.config.ts

I install my node packages via ddev pnpm install

The part that confuses me

Since I am installing my packages within the ddev container and node_modules is excluded, I did initially expect to see nothing on my host machine... no node_modules folder. That's obviously a false concept.

I've read the docs but it seems to assuming knowledge I don't have. Can someone explain or point me to a relevant source? Thanks in advance!

[hirasso]

Sometimes it helps to write down a question. Now I knew what do google for and found this:

https://instagit.com/ddev/ddev/what-are-ddev-performance-modes-mutagen-vs-bind-mounts/

[rfay]

Hi @hirasso - In recent releases ddev utility mutagen-diagnose will tell you all the things. Please see if it helps you.

[rfay]

If you have upload_dirs set up correctly, then your node_modules will show up on the host ane in the container, but it will be managed via a bind mount instead of by mutagen.

The docs link is https://docs.ddev.com/en/stable/users/install/performance/

[hirasso]

Thank you @rfay ! Now it makes total sense.