feat: allow easier deployment with default app schematics

[sinedied]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Other... Please describe:

What is the current behavior?

Currently, the generated starter app has 2 issues:

• It use a hardcoded port (3000) instead of using process.env.PORT with a fallback
• It does not allow to package the app properly using npm pack

Both these issues cause the default generated app to be undeployable on most cloud providers.

Issue Number: N/A

What is the new behavior?

This PR fixes the 2 issues above, so the default generated app can be deployed easily on most cloud providers.

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[sinedied]

Just saw that a similar PR was sent (currently in conflict), without the packaging part: #288

[jdubois]

This would definitely improve deployment on Azure 🎉

[kamilmysliwiec]

We're tracking this here #288

[sinedied]

@kamilmysliwiec as #288 seems stalled, and this one also adds proper packaging would it be ok if I add @BrunnerLivio as co-author on this PR to give him credits and re-open this one?

[BrunnerLivio]

@sinedied I think it makes sense to go with your PR instead! No worries about credits :)

If that is ok, re-open this one and I’ll close #288

[micalevisk]

this LGTM! @sinedied please update the docs as well https://docs.nestjs.com/first-steps#setup

@kamilmysliwiec can you please close #288 and review this one instead?

[kamilmysliwiec]

This has been discussed in the past and currently, we don't plan on making PORT the default. I left 1 PR open just in case we change our mind in the future.

[sinedied]

Hi @kamilmysliwiec, would it be possible to share a link to the discussion about not using process.env.PORT? I don't recall having seen one on this repo, and I would like to understand why you don't want this as a default.
The only reference I found is the issue about it on this repo, but you stated there that it should be made the default so I'm a bit confused: #125 (comment)
Thanks