coding.md

Takeaways from TDD and Software Design

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• TDD by its own CANNOT leads to good design, obviously
• TDD as a mechanism to help us to learn more about good design
• Software is "Soft" just because it can be changed, it is not meant to be settled in the stone
• Test-first programming can help the team to reduce defects but it will not lead to good design

Code qualities

Practice 5: Create CLEAN Code

• Cohesive
• Loosely coupled
• Encapsulated
• Assertive
• Nonredundant

Good code is CLEAN code

Simple design

• Passes its tests
• Minimizes duplication
• Maximizes clarity
• Has fewer elements

When a test is not a unit test

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• It talks to the database
• It communicates across the network
• It touches the file system
• It can't run at the same time as any of your other unit tests
• You have to do special things to your environment (such as editing config files) to run it.

TDD cycle

• Red: Write a failing test
• Green: Make the test pass as fast as possible
• Refactor: Take a look at your code

The Twelve-Factor App

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• One codebase tracked in revision control, many deploys
• Explicitly declare and isolate dependencies
• Store config in the environment
• Treat backing services as attached resources
• Strictly separate build and run stages
• Execute the app as one or more stateless processes
• Export services via port binding
• Scale out via the process model
• Maximize robustness with fast startup and graceful shutdown
• Keep development, staging, and production as similar as possible
• Treat logs as event streams
• Run admin/management tasks as one-off processes