Coursera Rails Module 3 Notes
I just finished the final module of this course. Overall I think it was a great course that provided a good overview of Ruby, and a thorough introduction to Rails. The next course dives into working with Databases and I am looking forward to learning more about Active Record.
Some Interesting Facts
- Rails has only been around since 2004.
- Startups love Rails since it makes it easy to do rapid prototyping.
- MVC has been around since 1979
Useful Resources
The lectures had a bunch of useful tools sprinkled throughout.- Learned about the Programmable Web API directory.
- Discovered the JSONView Browser Plugin which makes looking at JSON output in the web browser really nice.
Things I love about Rails
- Convention over Configuration. I love this, I love best practices, and I love having some guidelines to follow. Think less, do more.
- ORM makes it easy to swap out your DB as times goes on. Start dev in SQLite and should be able to seamlessly transition to MySQL, PostgreSQL, etc.
- Rake = Ruby Make, comes with a ton of useful built in utilities. For instance if you want to see all of the routes that your application is aware of you can run
rake routes. - Helpers (or view helpers) are reusable macros that can be used across any of your views. This is much cleaner approach than themacros that I am used to working with in Flask. There are at on of useful helpers built into rails, like "cycle" which makes it super easy to make striped HTML tables.
Things I learned
General Rails Tooling
- Finally have a solid understanding of how Gems, Bundler, and Rbenv work together.
- Learned about and used the HTTParty Gem
- You can use a Pessimistic Version Constraint (Love the name) in your Gemfile which basically says do not go over a certain version. Essentially you are betting against the house and saying that you believe that an update to one of your gems is going to break everything sometime in the future. (Trust me this happens all of the time).
Testing with Rspec and Capybara
Once again, I cannot say how happy I am that this course dives right into all sorts of testing. Kudos to the JHU team for thinking about this important skill even in an introductory course. This module talked about doing acceptance testing with Capybara. We learned about:- Capybara - Acceptance Test Framework
- PhantomJS - Headless Browser
- Selenium - Browser Driver for Firefox/Chrome
- Poltergeist - PhantomJS Driver for Capybara
Debugging
The built in debugging tools in development mode in rails are just awesome. You get an IRB console inside of the browser, this is super useful for debugging purposes. The gems that are responsible for this functionality are byebug and web-console.Deploying To Heroku
The course walked us through how to deploy an app to Heroku. Super simple of course. It is really nice to be able to see your application out in the wild!Pro Tip
The rails generator makes it super easy to create all of the files that you may need for a controller or model. However if you accidentally create a model with the wrong name and your project it huge it can be somewhat daunting to figure out what is safe to remove. You can reverse a rails generated command with:rails d $TYPE $NAME
rails g model recipeee
rails d model recipeee
Final Project
The final project is a simple web application called Recipe Finder that allows you to search for recipes using the food2fork api. I cleaned it up a bit and added an actual search bar (the assignment just had you add query params).Thank you for reading! Share your thoughts with me on bluesky, mastodon, or via email.
Check out some more stuff to read down below.
Most popular posts this month
- SQLite DB Migrations with PRAGMA user_version
- Microblog
- Setting up ANTLR4 on Windows
- How to Disable Wayland in Debian Testing
- Programming
Recent Favorite Blog Posts
This is a collection of the last 8 posts that I bookmarked.
- The contagion of fear from The Observation Deck
- The revolt of the reader from The Observation Deck
- Deeper dive: Were Touch Bar’s problems software rather than hardware? from Unsung
- Joining Cursor from Fatih Arslan
- Pluralistic: Digital sewer socialism (08 Aug 2026) from Pluralistic: Daily links from Cory Doctorow
- Pluralistic: Enshittification and Reverse Centaurs go global (29 Jul 2026) from Pluralistic: Daily links from Cory Doctorow
- AI Mania Is Eviscerating Global Decision-Making from Ludicity
- The default person from https://popagandhi.com/
Articles from blogs I follow around the net
“From digital mischief to outright destruction”
The 1980s and 1990s PC viruses were a special breed. The MS-DOS operating system wasn’t particularly secure – few home computer operating systems were back then – so viruses could spread quickly, and many did. Some of the viruses focused more on actually w...
via Unsung November 11, 2026The villa of Ormen
As a child, I was never a fan of any actor or singer. David Bowie is the closest thing to a “music idol” I’ve ever had. I never had a poster of him on my wall, or a T-shirt with his face on it, but he was a constant presence in my playlists, to the point w...
via Personal Site of Andrei N. Ciobanu November 11, 2026Candidate Statement for the 2026 W3C TAG Election
Group photo of the W3C TAG in July 2022 with me to the left of Sir Tim Berners-Lee (inventor of the Web and TAG chair emeritus). Photo credit: Dan Appelquist I had the great honor of being elected to the TAG by the W3C membership in 2020 and again in 2022,...
via Lea Verou’s blog November 11, 2026Generated by openring