Mobius onboarding Guide

Mobius
Mobius is our recommended architecture for building Android applications. We also feel that it is much easier to learn Test-Driven Development by starting out to build apps using Mobius.
Day 1: Introduction to Mobius & TDD (4:50 hours)
Theory: Introduction to Mobius (1 hour)
Eliminating the moving parts using functional programming
Pure functions
State transition diagrams
Model & Event
Pairing Activity: The counter app state transition diagram (1 hour)
The update() function
Introducing the UpdateSpec class
Test driving the counter update() function
Wiring the update() function to the UI
Theory: Test-Driven Development (30 minutes)
Principles of TDD
​YAGNI 
The red, green, and refactor cycle
TDD as a design practice
Recap (20 minutes)
Key takeaways
Reading materials for the next day
​https://github.com/spotify/mobius/wiki/Concepts​
​https://blog.cleancoder.com/uncle-bob/2016/03/19/GivingUpOnTDD.html 
Day 2: Mobius Effects & Effect Handlers (5:05 hours)
Reflection of Day 1 and discussion around reading materials (30 minutes)
Pairing Activity: Login Screen update() Exercise (2 hours)
Introducing effects & effect handlers
Login example state transition diagram
Test driving the login update() function
Identifying the primitive obsession code smell (Watch this)
The “What to test?” problem
Relationship between the number of execution paths and tests
Test driving the Username and Password classes
Modeling async state transitions
Completing the update() function
Pairing Activity: Materializing effects using effect handlers (1:30 hours)
State verification vs. behavior verification
Introduction to Mockito
Low confidence behavior verification tests
Writing the first effect handler
Using the RxJava SubtypeEffectHandler
Action, Consumer, and ObservableTransformer
Errors of first-class citizens
Using Scheduler in tests
Pairing Activity: Introduction to Views and View Renderers (45 minutes)
Using mockito to verify view rendering logic
Recap (20 minutes)
Key takeaways
Day 3: Mobius, the final bits (5:35 hours)
Reflection of Day 2 (30 minutes)
Pairing Activity: Creating the shell (45 minutes)
Wiring all the Mobius components
Saving and restoring model state
The @Parcelize annotation
Caveats of saving data using Android’s Parcelable interface
Pairing Activity: Subtle bugs introduced by async operations (45 minutes)
Handling normal flow of execution using the init() function
Handling edge cases using the init() function
Using the InitSpec for testing normal flow and edge cases
Recap (20 minutes)
Day 4, 5, and (possibly 6): Building the NASA APOD Apps (14:50 - 22:50 hours)
Reflection of Day 3 (20 minutes)
Individual Activity: NASA APOD Application (8 - 16 hours)
Step 1: Drawing the state transition diagram
Step 2: Writing the init()the update() tests
Step 3: Writing Effect Handler tests
Step 4: View and View Renderer Tests
Step 5: Wire up the imperative shell
Code review and addressal (1:30 hours)
Recap (1 hour)
Points of Confusion
Effect are more closer to intention for side-effect than performing a side-effect
Representing decision making in state diagram

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Contents

Mobius

Day 1: Introduction to Mobius & TDD (4:50 hours)

Day 2: Mobius Effects & Effect Handlers (5:05 hours)

Day 3: Mobius, the final bits (5:35 hours)

Day 4, 5, and (possibly 6): Building the NASA APOD Apps (14:50 - 22:50 hours)

Points of Confusion