How to npm config save into project .npmrc file?

Question

I am hoping to run npm config to set values in a project's .npmrc file. Docs dont seem to say how to specify a file to save the values into.

Looking for something like npm config --file /path/to/repo/.npmrc set key value

Trying to use it for a build script that needs to build a .npmrc file from env vars.

Answer 1

It is baffling that this is seemingly still not directly supported as of npm v6.9.0.

It's a bit awkward, but if your npm version is recent enough, you can repurpose the --userconfig option to make npm config operate on a project-specific .npmrc file.

E.g., from a given project's root folder, the following command project-locally configures pwsh (PowerShell Core) as the shell to run scripts with, by making npm config operate on the local .npmrc file via --userconfig:

# Updates .npmrc in current dir
npm config set script-shell pwsh --userconfig .npmrc

Note: As Kerry Johnson points out:

• The target file is rewritten as a whole, in the course of which any comments (#-prefixed lines) in the original file are lost (but all key-value pairs are preserved).

• The config keyword is optional in this case, so the following will do:

  npm set script-shell pwsh --userconfig .npmrc
  

Answer 2

You can do a chroot, build your config file on ~/.npmrc and then copy it on the right location.