npm start defaults don't match npm init -y defaults

[ashleygwilliams]

npm init -y sets main as index.js in the package.json
npm start assumes a server.js

there's an implicit assumption in my head, that npm start will assume main.
these should probably tell a coherent story?

so maybe:
A. npm init -y should set main to server.js
B. npm start looks for a index.js
C. npm start looks for something by default, but will let main override it

not sure what i prefer. i usually have a server.js in the root that consumes some index.js in a src or app directory , so A matches how i dev, but i wonder if we shouldn't do some research or thinking on what we think is the most reasonable default. C is by far the best one IMO, but requires more work that touches more things.

p.s. this was discovered while working on the docs: https://github.com/npm/docs/pull/436

[othiym23]

A. breaks the alignment of npm init with the Node module loader (which defaults to load index.js when you require('packagename'), and is probably a nonstarter for that reason.
B. or C. are both feasible (I favor B over C, because it's simpler), but both are semver-major breaking changes. We don't know how many people are relying on this implicit behavior today, and have no way to know just by looking at the registry. So, in order to avoid breaking people's deployments, we'll need to make sure this is advertised as a breaking change. Tagging to the 4.x milestone as a result.

[othiym23]

Probably npm start should default to server.js, fall back to main if no server.js exists, and then fall back to index.js. I think this is still a semver-major change, though, as something that affects tools that are beyond our visibility as maintainers.

[zkat]

I feel pretty fine with the way it is right now, and it actually feels pretty good for libraries that have both an API and a server (which is more common than you'd think) -- I do think that we could definitely put more effort into making people aware of this dichotomy so they can take advantage of it more.

[zkat]

Example: kmanion/senpai#3, and I think they had a pretty good reaction to it once it was clarified.

Your strange conventions are making some sense. :)
@strand

[othiym23]

There's a consensus about what the defaults should be, and at the same time there's very little chance that the CLI team is going to have the cycles to get to this within the next 6-12 months, so I'm going to close this for now. Anyone interested in patching this behavior (hint hint @ashleygwilliams) should be aware that the defaulting behavior that points to server.js actually lives in read-package-json (it probably shouldn't, so pulling that out would be a useful change on its own), so changing this behavior is likely to be a two-part process of patching read-package-json and then including the patched version of that in npm. Thanks for getting the ball rolling with this, @ashleygwilliams!