fix(build): Require correct dependencies for prod build

[simison]

Some of the dependencies required by npm run start:prod aren't currently installed with npm install --production.

See #1852 for reference.

This also moves some of the require's in Gulpfile inside tasks so that they wouldn't be required if unrelated tasks are run (i.e. start:prod task).

Also changed several semver ranges from ^ to more strict ~.

[simison]

To test this, do:

git clone https://github.com/simison/mean.git mean-simison
cd mean-simison
git checkout restructure-prod-build
npm install --production
NODE_ENV=production npm run start:prod

[simison]

I'd be especially interested to have @mleanos look at those protractor changes I made! You wrote that feature originally, right?

[simison]

FYI @Ghalleb tested this (#1852 (comment)) and says it seems to work fine.

[mleanos]

LGTM. I've tested this locally, and deployed to Heroku using Production environment settings. I ran into an issue with our gulp default task, that I'll explain in a separate comment. However, these changes seem to accomplish their goals.

Out of curiosity, what should the production deployment flow look like? Should we run the tests?

[mleanos]

I ran into an issue with our default Gulp task. It actually sets the NODE_ENV to "development". And the Procfile starts the app using gulp default. This will cause the application to run in Development mode regardless of what NODE_ENV is set to. In my case, I want my Heroku deployment to run in "production" mode.

If I remove the 'env:dev' from the default Gulp task, the application runs in whatever NODE_ENV I set in my environment variables.

@simison @Ghalleb Do you have thoughts on this?

[simison]

@mleanos I'm not really familiar with Heroku. What would you recommend?

[simison]

@mleanos On second thought:

• npm start should probably just use existing NODE_ENV and default to development. In package.json scripts we could have:

'start': 'if [ $NODE_ENV == "production" ]; then npm run start:prod; else npm run start:dev; fi'

... but that test could be also at Gulpfile.js — might be even more clear to have it there? I'm not exactly sure how well bash conditionals work e.g. in Windows machines.

• npm run start:prod and npm run start:dev stick to using `'env:' Gulp tasks.

[Ghalleb]

If you look at my PR #1854, I changed npm start to npm run start:prod in the procfile as this file is tipycally used for production only...

[simison]

@Ghalleb thanks! So I'll merge this and that change can be done in your PR.