Update Dockerfile to improve build time and size

[jelaniwoods]

The current base image, gitpod/workspace-full:latest, that we've been using is very large— around 7.19GB before any appdev stuff is installed. Afterwards the images end up being 8-9GB!

This limits the number of images you can store on your computer, increases build time, and increases the time it takes to push to Docker Hub.

The proposed changes start from an ubuntu base image that starts at 72.9MB. Once all the necessary programs are installed, the image size is around 2.21GB (2.73GB with R, Python3, wkhtmltopdf, graphviz, and imagemagick installed)— which is much more manageable!

Starting from ubuntu, we need to install

• curl
• wget
• gnupg2
• default-jdk
• sudo
• git
• rvm
• postgresql
• postgresql-contrib
• libpq-dev
• psmisc
• lsof
• r-base and dependencies
• wkhtmltopdf and dependencies
• python3 dependencies

We also need to make a non-root user (gitpod) and configure it to work with sudo

https://github.com/firstdraft/appdev_template/blob/9922296e84cfe4b1c63244a92ce1e205c6d41b11/files/Dockerfile#L24-L28

Everything else is the same or were hacks to get around configuration in the gitpod/workspace-full image that are no longer necessary.

The only layers that need to re-build between projects are

https://github.com/firstdraft/appdev_template/blob/6bb2fa0bb4ab7e2c22fefe260b7a8d14eb085721/files/Dockerfile#L58-L64

so the bottleneck is basically sassc and to a lesser degree nokogiri.

bundler is always installed so we don't have to worry about having the wrong version of bundler installed.

Heroku CLI is always installed so it's up to date and students don't see warning messages about it being out of date.

This was tested with this repo: https://github.com/appdev-projects/photogram-final/tree/jw-fall20-updates

[raghubetina]

Great thinking! Are there any other libraries that would be handy to have pre-installed in addition to Chromedriver? I can think of Imagemagick (used by lots of image processing libraries), Graphviz (used by rails-erd). Any others?

[raghubetina]

Perhaps having Python and/or R installed might be useful for demonstrating how to shell out to other programs?

[raghubetina]

Are there any libraries that would be helpful to pre-install for VSCode extensions? Beautifiers? Intellisense?

[raghubetina]

Perhaps wkhtmltopdf (used by wicked_pdf)?

I've fielded a handful of final projects that need to generate e.g. PDF invoices and usually recommend Prawn since it's pure Ruby with no dependencies, but I've been preferring wicked_pdf over Prawn lately since the former lets you write HTML and CSS rather than learn a DSL.

[jelaniwoods]

@raghubetina I've made updates to include:

• Imagemagick
• Graphviz
• Python3
• R
• wkhtmltopdf

Could you take another look?

[raghubetina]

This looks great and I would be happy merging. Curious though about whether installing Solargraph or something similar would prevent those constant error pop-ups that we see?

And my other q re: formatters for e.g. rb and erb files?

[jelaniwoods]

Curious though about whether installing Solargraph or something similar would prevent those constant error pop-ups that we see?

@raghubetina Which error messages do you mean? I haven't seen any popups in a few quarters. Gitpod shouldn't have Solargraph installed by default anymore and the settings were reverted in this PR https://github.com/firstdraft/appdev_template/issues/153

The htmlbeautifier extension has been added to all projects this quarter, done in https://github.com/firstdraft/appdev_template/pull/152 .

I've only ever used Rubocop before, is there a Ruby formatter that you prefer that follows the same convention of Format Document in the command palette?

[raghubetina]

@jelaniwoods I like Rufo — it's a bit more unobtrusive than RuboCop. Can we hook this up to "Format Document"?

Gitpod shouldn't have Solargraph installed by default anymore and the settings were reverted in this PR #153

Gotcha, maybe I was just seeing them on old repos that I had previously forked. I'm still curious about the benefits of Solargraph/Intellisense but until we observe benefits in our own coding workflows I think we can leave it out for students.

The htmlbeautifier extension has been added to all projects this quarter, done in #152 .

Great.

[jelaniwoods]

@raghubetina rufo is now installed and with this extension it hooks into Format Document and works as expected.

[jelaniwoods]

Perhaps it worth watching this to see what extensions and settings to use.

[raghubetina]

Good idea; especially now that full VSCode is coming to Gitpod.