Rubymonk training

Read the following Rubymonk articles:

• Ruby Primer: Ascent (archived copy)
• Metaprogramming Ruby (archived copy)
• [Metaprogramming Ruby: Ascent](http://rubymonk.com/learning/books/...

Learn

Method lookup

Understand all the terms in How Ruby method lookup works, in particular:

• include
• extend
• singleton class
• prepend

Do you understand why object.extend(SomeModule) is the same as object.singleton_class.include(SomeModule)?

How does include and extend work together with inheritance?

You may also read more about the Ruby Object Model, if all o...

Your MovieDB gained traction and is now a popular tool among cineasts. This comes with a downside: You noticed a degrading content quality, which only can be contained by introducing a new moderation process. While everyone can keep adding new movies, they should at first be drafts that require a mandatory review by an administrator before publication.

Requirements

Movies in MovieDB should have one of the following workflow states:

• draft
• pending
• published
• declined

A movie always begins as a draft and then t...

Exercise 1: Maps

• In MovieDB, add a new field “Principal filming location”.
• In a movie’s show view, geocode that location and show a Google map centered around it
• Now write an E2E feature that tests that the map shows the correct location.

Hints

• The purpose of this lesson to learn interacting with external APIs from JavaScript. Even though this exercise can be implemented trivially by embedding a Google Maps iframe, don't do that for the purpose of learning...

Exercise 1: XML

On the start page of your Movie DB, show the title of a random movie that is coming soon to theaters.

• There's an XML feed for this at https://www.filmjabber.com/rss/rss-upcoming.php
• Manually parse the feed using Nokogiri, don't use an RSS gem for the purpose of this card.
• Update it once a day (using whenever)

Tip

Consider the best place to put the new logic. Should it be an existing class or new classes?

Exercise 2: JSON

Automatically ret...

Jasmine is a great tool to unit test your JavaScript components without writing an expensive end-to-end test for every little thing.

Jasmine is a purely client-side tool. It cannot ask Rails to render a view or access the database. Any HTTP calls must be mocked.

Learn

What do we test with Jasmine?

Just as unit tests are a direct way to closely look at your classes, Jasmine is a very direct way to look at your JavaScript components.

For example, when you want to test that a date picker opens a calenda...

Goals

• Learn to store attachments in a way that is accessible by authorized users only
• Learn to prevent users from uploading malicious content

Resources

• Deliver CarrierWave attachments to authorized users only.
• File uploads should validate the file extension
• [Self-expiring URLs with Apache](https://makandracards.com/makandra/70814-s...

Learn

Read the following material:

• World's shortest UI/UX design course
• Easiest Way to Pick UI Colors
• 7 Rules for Creating Gorgeous UI (Part 1)
• 7 Rules for Creating Gorgeous UI (Part 2)
• [Visual design rules you can safely follow every time](https://anthonyhobday.com/sideprojects/safe...

If you've stumbled over display: grid while reading the Flexbox material of the previous card - we've got you covered!
Let's dive into this topic with a quote:

Flexbox is made for one-dimensional layouts and Grid is made for two-dimensional layouts.

You will learn more subtle differences in the linked material below, but you can remember this as a rule of thumb.

Resources

• Comprehensive Guides:
  • [An Interactive Guide to CSS Grid](https://www.joshw...

Many of our clients can't or don't want to design their user interfaces. In the absence of a good UI design, you should always be able to come up with a default. Since the user interface makes up 70% of a typical web application, this is closely related to requirements analysis and cost estimation.

Learn

Talk with your mentor about the following topics:

• Extracting nouns from requirements prose
• Drawing ER diagrams and minimizing boxes
• Why nouns from the client domain do not always map to Ruby models 1:1. E.g. although an "addre...

In our daily life as web developers we are constantly faced with technical problems that can be solved with a variety of (sometimes vastly different) technologies. Choosing the right tool for the tasks is crucial for our mid- and long term success.

Our technology radar card documents what we're currently investigating either to replace or introduce to our stack of tools. Start this card by skimming over the linked resource.

Discussion

Growing Rails application...

Adopting legacy Rails apps

Talk to your mentor about how we're approaching applications that are either old or abandoned by a different team earlier:

• Add E2E tests for the happy path. Other than unit tests, E2E tests will not break when we refactor later.
• Always add tests on whatever we work on.
• When you work on something, improve that part of the code.
• Make sure setup for a new developer is as frictionless as possible (ideally it's bin/setup).
• Make sure deployment is as frictionless as possible.
• Setup failure notification...

Some tasks in a web application are better not done live when a user request a page, but in the background. Examples are

• longer running tasks
• tasks that are not tied to user interaction
• tasks that can fail, and may need to be retried

Our two main mechanisms for background processing are

• cronjobs (managed with whenever)
• job queues, usually with Sidekiq

Learn about cronjobs

• Read [HowTo: Add Jobs To cron Under Linux or UNIX?](http:...

Learn

Resources

• Rails Guide: Internationalization API
• Guide to localizing a Rails application
• Locale-aware helpers in ActionView::Helpers::NumberHelper
• Accept-Language HTTP header. Can be parsed with a gem like [accept_language](https://github.com/cyril/accept_lan...

Research

• Action Mailer Basics and Previews
• Chapter "Task H1: Sending Mail" from Agile Web Development with Rails 7.2 (in our library)
• Ensure that the receiving e-mail is valid
  • Using the Truemail gem to validate e-mail addresses
• ...

Web technology is a broad field and you cannot be an expert in all aspects.

However, it is useful to have a rough understanding of common terms and buzzwords, so that you don't seem uninformed when talking to a client or other developers.

Get an overview

Search the Internet for each of the following terms. Only take a couple of minutes for each and don't get into too much detail. Do get a rough idea about the advantages they promise.

• Continuous Integration or CI
• Single-Page Application or SPA
• `Progressiv...

Research

• What is rake good for?
• Take a look at some of the Rake tasks that Rails gives you (rake -T within a Rails project)
• Find the code that defines the rake stats task in the Rails gems
• What are some ways how a Rake task can execute another task?
• What does it mean if a Rake task "depends" on another task? E.g. understand what it means for a Rake task within a Rails app to depend on :environment.
• Understand that Capistrano tasks are also defined using the Rake DSL, but a Capistrano task is not automatically a...

Storing a tree

For each movie in MovieDB, we want to track which other movie it was inspired by. For example:

• "Interstellar was inspired by 2001"
• "Inception was inspired by The Matrix"

Start by adding a field Movie#inspiration_id. In the movie form, I should be able to select the inspiring movie.

The list should:

• include all the movies that were released in previous years
• not include the movie itself
• not include a movie that was itself inspired by the movie that is being edited.

Traversal

In the...

Goals

While the Software Design Basics card tried to make a point about writing self explanatory code, it's still essential for every application to maintain a good documentation. The README file is essential for fellow engineers to get started quickly, as it contains documentation of all major moving parts of the given app.

Resources

• README Driven Development
• [Writing a README for ...

We've already learned how to integrate user-provided images uploads to our application in 205 basic file uploads and image versions. In this bonus chapter, we want to dive deeper.
Common web apps often include static images like icons and application logos next to the dynamically created images versions of uploaded files. To serve all of those with limited bandwidth and high quality, images formats and compression strategies have to be carefully selected.
...