add deploy documentation for heroku and app engine

[RensDimmendaal]

I've taken a stab at creating deployment instructions. Cheers.

Mentions in issues:

• Request of @jtpio in Deployment on Google App Engine does not show widgets #221 (comment)
• Document deploying voila to heroku #184

[SylvainCorlay]

Thanks @RensDimmendaal! We will definitely review this soon!

[pbugnion]

Thanks for writing this! I had a look at the heroku part. It looks great! I had a couple of thoughts:

1. I think it would be useful to add a sentence at the end on resolving errors.

For instance, a sentence like the following would be useful at the end:

To resolve issues, it is useful to see the logs of your application. You can do this by running:

heroku logs --tail

2. Separately, when I discussed this with Yuvi, we mostly agreed that we should bias people unfamiliar with deployment strongly towards Heroku. It seems to me that that's the easiest route to follow to get something served up.

Regardless of what we choose, I think it's important to give guidance as to where to deploy for users with little prior experience. A sentence like the following at the beginning would be appropriate:

If you are not sure where to deploy your app, we suggest Heroku. You can test deploying and serving your app without having to enter any credit card details, and with very little prior experience of deployments.

[RensDimmendaal]

Thanks for the feedback @pbugnion. I've implemented all your suggestions

[pbugnion]

Thanks! I think the Heroku parts look great. I've made one more tiny comment.

It might be useful for someone with experience deploying on GCP to review those parts (@jtpio ?)

[jtpio]

Thanks @RensDimmendaal!

I haven't tried GCP yet but I think @maartenbreddels mentioned something about it and might be able to have a look.

Also referencing @martinRenou's standalone example for deploying voila on Heroku: https://github.com/martinRenou/voila_heroku

[jtpio]

This line is giving a WARNING: Unexpected indentation error when trying locally.

Suggested change

	and with very little prior experience of deployments.
	and with very little prior experience of deployments.

[RensDimmendaal]

fixed. I dont' use a linter for the docs. What linter do you use? Maybe it would be a good idea to add it to the doc-requirements?

[jtpio]

@RensDimmendaal I went through (and tested) the steps to deploy to App Engine.

Left a few comments and fixes, but overall it looks good!

[maartenbreddels]

Very well written, I can confirm that the steps work as well for GEA, except that it's very flakey (websocket has trouble connecting).
I assume @martinRenou 's changes are requested, I'll merge this soon if I hear no objections.

[jtpio]

@maartenbreddels it looks like these changes were implemented in the last two commits. So it should be ready to go.

[gitjuanfmunoz]

Hi, I'm trying to deploy according to instructions and I have the following error: (heroku logs --tail)

Help!!

2019-11-26T22:27:06.000000+00:00 app[api]: Build succeeded
2019-11-26T22:27:49.651017+00:00 heroku[web.1]: State changed from starting to crashed
2019-11-26T22:27:49.555688+00:00 heroku[web.1]: Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 60 seconds of launch
2019-11-26T22:27:49.555774+00:00 heroku[web.1]: Stopping process with SIGKILL
2019-11-26T22:27:49.635560+00:00 heroku[web.1]: Process exited with status 137
2019-11-26T22:27:51.367698+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=tigomedalia.herokuapp.com request_id=9eaa4388-1383-4485-99d7-46094e3883cd fwd="181.54.83.183" dyno= connect= service= status=503 bytes= protocol=https
2019-11-26T22:27:52.420063+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=tigomedalia.herokuapp.com request_id=5f4707ef-ff55-4788-892b-eb59a8a5255f fwd="181.54.83.183" dyno= connect= service= status=503 bytes= protocol=https
2019-11-26T22:27:57.593708+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=tigomedalia.herokuapp.com request_id=223a7161-78aa-4fc0-bb06-48c01bab5283 fwd="181.54.83.183" dyno= connect= service= status=503 bytes= protocol=https
2019-11-26T22:27:58.073835+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=tigomedalia.herokuapp.com request_id=914cb4c7-c334-4f17-a7d4-24c185a08bfe fwd="181.54.83.183" dyno= connect= service= status=503 bytes= protocol=https
2019-11-26T22:31:24.000000+00:00 app[api]: Build started by user juan.francisco.munoz@gmail.com
2019-11-26T22:32:19.128001+00:00 heroku[web.1]: State changed from crashed to starting
2019-11-26T22:32:18.801571+00:00 app[api]: Deploy 401d5030 by user juan.francisco.munoz@gmail.com
2019-11-26T22:32:18.801571+00:00 app[api]: Release v8 created by user juan.francisco.munoz@gmail.com
2019-11-26T22:32:33.257734+00:00 heroku[web.1]: Starting process with command voila voila —-port=45767 map_plot.ipynb
2019-11-26T22:32:39.364585+00:00 heroku[web.1]: State changed from starting to crashed
2019-11-26T22:32:39.348634+00:00 heroku[web.1]: Process exited with status 1
2019-11-26T22:32:39.183608+00:00 app[web.1]: Traceback (most recent call last):
2019-11-26T22:32:39.183646+00:00 app[web.1]: File "/app/.heroku/python/bin/voila", line 11, in
2019-11-26T22:32:39.183875+00:00 app[web.1]: sys.exit(main())
2019-11-26T22:32:39.183923+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.7/site-packages/traitlets/config/application.py", line 663, in launch_instance
2019-11-26T22:32:39.184534+00:00 app[web.1]: app.initialize(argv)
2019-11-26T22:32:39.184580+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.7/site-packages/voila/app.py", line 342, in initialize
2019-11-26T22:32:39.185097+00:00 app[web.1]: raise ValueError('provided more than 1 argument: %r' % self.extra_args)
2019-11-26T22:32:39.185222+00:00 app[web.1]: ValueError: provided more than 1 argument: ['voila', '—-port=45767', 'map_plot.ipynb']
2019-11-26T22:32:53.000000+00:00 app[api]: Build succeeded
2019-11-26T22:33:13.089044+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=tigomedalia.herokuapp.com request_id=c0f5a19d-d355-4293-9e73-2e3d28e47244 fwd="181.54.83.183" dyno= connect= service= status=503 bytes= protocol=https
2019-11-26T22:33:14.206534+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=tigomedalia.herokuapp.com request_id=b410e6da-5fea-4dda-bdc2-4077fa047617 fwd="181.54.83.183" dyno= connect= service= status=503 bytes= protocol=https
2019-11-26T22:35:27.859132+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=tigomedalia.herokuapp.com request_id=98713be4-aac9-4aff-8054-ac7c0648b16f fwd="181.54.83.183" dyno= connect= service= status=503 bytes= protocol=https
2019-11-26T22:35:28.477759+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=tigomedalia.herokuapp.com request_id=98f14e69-2506-4834-a3c8-1ec54d560c4c fwd="181.54.83.183" dyno= connect= service= status=503 bytes= protocol=https

[jtpio]

@juanfranciscomunoz the logs say:

Starting process with command voila voila —-port=45767 map_plot.ipynb

Where voila appear twice. What does your Procfile look like?

[sruthiiyer]

Can someone tell how to deploy voila in GCP?