CHIPS (Programming assignments)

To complement the Content-Oriented Didactic (COD) materials such as the book and lectures, CHIPS (Coding & Hands-on Integrated Projects) provide hands-on skills practice and are keyed to specific sections in the book. This section describes how to use them with Codio. The book's website has other options if you don't wish to use Codio, but we have pretty extensive automated workflows that are optimized for Codio, for publishing both the book content itself and these CHIPS along with their autograders.

If you're using Codio, all you really need to know is how the CHIPS work—see below. If you want to use the CHIPS outside of Codio, or contribute to their development, look at the README in the CHIPS repo (visible to registered instructors).

Here's a quick summary of the assignments, presented in the order in which they appear in the ESaaS textbook. Following the summary are details on how to edit and dry-run each assignment, and any noteworthy caveats. There are three types, as indicated in the table below:

1. (A)utograded using Codio: The single repo saasbook/chips includes everything needed to generate (a) student-facing starter code repo, (b) Codio autograder (including files that are hidden from students when they use Codio), (c) Codio "Guides" panels to walk the student through the assignments, (d) reference solution. That repo's README includes generic instructions for how to edit, test, and deploy Codio-autograder-based CHIPS. Some CHIPS also include files for manually configuring Gradescope-based autograding, but Gradescope is no longer officially supported, so use those files at your own risk.

2. (P)rairieLearn autograding: The questions are done in the PrairieLearn assessment authoring system and have autograders there.

3. (S)elf-graded: CHIPS involves coding, but rather than an autograder, students run tests themselves that are included in the student-facing code repos. It's up to you if you want to verify that they've done so (e.g. by having them submit a screenshot, etc.)

4. (C)omprehension-based with some autograding: CHIPS involves minimal or no coding, but rather performing some tasks and answering self-check questions about them. The tasks can be performed in the Codio IDE's terminal window, and in some cases the questions are built into the Codio version of the assignment as unlimited-attempt selected-response/short-answer questions.

The relative effort of each CHIPS is indicated by one bullet (1-2 hours of effort), two bullets (2-3 hours), or three bullets (a potentially multi-day assignment). Here are the book sections in which the CHIPS occur, along with their effort ratings.

Sec.#	Type	Effort	Description
2.5	A	••	Ruby Intro: gentle intro to Ruby idioms, including running instructor-provided unit tests to check your answers
3.3	C	•	HTTP and URIs: intro to HTTP requests, URIs, and cookies, using curl and netcat to see raw data, using the esaas-cookie-demo app (source).
3.7	A	•••	Create and Deploy a Simple SaaS App: de-mystifies the creation of a SaaS app (a simple word-guessing game using Sinatra) including use of an external service, and how to think about RESTfully "wrapping" application logic in SaaS.
4.3	S	•	ActiveRecord Basics: write ActiveRecord queries against a provided seeded database.
4.5	S	•	Rails Routes (self-graded): not actually a homework assignment, but a simple app that lets students enter syntactically valid Rails routes and understand the RESTful routes that Rails would generate for them.
4.7	C	••	Word Guesser on Rails (comprehension with reference solutions): use the same Word Guesser game logic and Cucumber scenarios as CHIPS 3.7, but scaffolds a walkthrough of how to deploy the app with Rails instead of Sinatra, as an on-ramp to understanding the complex Rails framework.
4.9	S	•••	Hello Rails (self-graded): create a brand-new Rails app (RottenPotatoes) from scratch, including routes, database setup, using the debugger, and deploying to Heroku.
5.3	A	•••	Rails Intro: enhance RottenPotatoes to filter and sort movie lists.
5.7			Associations and SSO/WebAuthn login (TBD: not finished yet)
6.9			AJAX Enhancements to RottenPotatoes (TBD: not finished yet)
7.7	A	•••	Intro to BDD and Cucumber (): write features to test happy and sad paths of RottenPotatoes.
7.9		••	BDD for New Feature: write scenarios and then backfill the code to make them pass, using BDD to drive the code for a new RottenPotatoes feature "Find movies with same director." Another goal is to achieve a threshold level of C1 coverage using SimpleCov.
8.5*	P	••	Intro to RSpec: Introduction to RSpec test writing, including the use of doubles, before-blocks, and the arrange/act/assert pattern, using Faded Parsons Problems. *This CHIP is part of the shared PrairieLearn question collection, rather than being in the saasbook/chips repo.
10.5	A	!	Agile Iterations Two (or more) full iterations of Agile adding features to an existing (legacy) app. See the separate section on CHIPS 10.5.
12.8		••	Exploiting Caching and Indices: improve the performance of RottenPotatoes by adding database indices to speed up key queries.

Optional additional CHIPS (not referenced in textbook)

• Oracle of Bacon: Build a simple command-line app that uses external services in a SOA, including parsing XML responses.

• Design Review: We use this in the project portion of the course. This is not a programming assignment but rather a 3-part scaffolded process for doing design reviews and technical presentations. (Each part can be used more or less independently.) It is intended to be used in conjunction with student teams doing their own open-ended projects, so no code is provided. In part 1 (Design Review), teams are paired up and each team evaluates the other's design and gives feedback on possible improvements. In part 2 (Presentation), teams give technical presentations about the design review; these are peer-evaluated (or instructor-evaluated) according to a provided rubric. In part 3 (Handoff), teams modify their repos as needed to ensure the project is easy for another team to pick up and continue working on.