Build fails when a service has a nodejs dependency in a sub-folder

[paultranvan]

Suppose we have a service in targets/services/service.js, that requires a file in targets/services/subdir/file.js, that itself requires a nodejs dependency, e.g. fs.
When trying to build the service with cozy-scripts through yarn watch, an error will throw: Module not found: Error: Can't resolve 'fs'.
This is because cozy-scripts will only consider js files in targets/services/ but not in subfolder:

create-cozy-app/packages/cozy-scripts/config/webpack.config.services.js

Lines 15 to 19 in 4b790b8

	servicesPaths.forEach(file => {
	if (!file.match(/^[^.]*.js$/)) return
	var filename = file.match(/^([^.]*).js$/)[1]
	servicesEntries[filename] = path.resolve(path.join(servicesFolder, file))
	})

Hence, any file in subdir/ requiring a nodejs primitive will fail.

A workaround would be to recursively find any .js file in targets/services/service.js, but I'm not sure this is the correct approach, as any file will be a new entry:

create-cozy-app/packages/cozy-scripts/config/webpack.config.services.js

Line 33 in 4b790b8

entry: servicesEntries,

We met this issue with @JulienMirval when trying to use cozy-konnector-libs in a service: https://github.com/JulienMirval/dissec_cozy/blob/ee206472c49c723af630e1d740c1e0384dc73b64/src/targets/services/helpers/model.js#L2

Any thoughts?