Add custom metadata or config to package.json, is it valid?

Question

I have seen (don\'t remember where) a package.json file with custom keys starting with an underscore:

{
    \"name\": \"application-name\"
  , \"version\": \"0.0         


        

Answer 1

Given the nature of JSON and this statement from the Nodejitsu documentation I don't see anything wrong with that.

NPM itself is only aware of two fields in the package.json:

{
   "name" : "barebones",
   "version" : "0.0.0",
}

NPM also cares about a couple of fields listed here. So as long as it is valid JSON and doesn't interfere with Node.js or NPM everything should be alright and valid.

Node's awareness of package.json files seems extends to the main field. Ref.

 { "name" : "some-library",
   "main" : "./lib/some-library.js" }

If this was in a folder at ./some-library, then require('./some-library') would attempt to load ./some-library/lib/some-library.js.

This is the extent of Node's awareness of package.json files.

To avoid possible conflicts you should prefixing your keys with some character or word. An underscore is a common variant.