Clean Code Principle for Software Engineer

Clean Code Principle for Software Engineer

Transcript

1. Clean Code Principle for
   Software Engineer
   Didik Tri Susanto, 26 Oct 2022
   

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2. Contents
   ● Why Clean Code?
   ● Benefit & Goal
   ● Principle
   ● Approach
   ● Dealing with Legacy Code
   

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3. Why Clean Code
   

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4. Good Code VS Bad Code
   

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6. What is Clean Code
   “Clean code always looks like it was written by someone who cares”
   ~ Michael Feathers
   

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7. Not only working software, but also
   well-crafted software
   Manifesto of Software Craftmanship
   

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8. Benefit & Goals
   

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9. ● Increase Maintainability == Reduce maintenance cost
   ● Reduce onboarding time for new developer
   ● Reduce tech debt
   ● Reduce time to add or modify existing features
   ● Happy developer
   

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11. Principles
    

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12. Code for Human
    

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13. “Always code as if the person who ends up maintaining your code is a violent
    psychopath who knows where you live.”
    

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14. Follows Coding Standard
    ● PHP: PHP Standard Recommendation (PSR)
    ● Javascript: Airbnb coding standard
    ● Go: Effective Go
    

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15. Code Review or Pair Programming
    ● Sharing context
    ● Finding insight and alternative solution
    ● Knowledge transfer
    ● Managing your ego
    

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16. Be patient, writing good codes takes time
    

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17. Technical Approach
    

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18. Meaningful Names for Variables, Methods, Classes,
    Arguments
    ● Should be sufficient enough to understand the purpose or context
    ● One should not have to read the whole code to figure out what a function does or what a class
    represents or to understand why a variable exists
    ● No need comments
    

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19. Bad Good
    

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20. Avoid Magic Values
    Bad Good
    

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21. Even Better …
    

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22. Other naming best practices
    ● Name functions as verbs. Ex: save, create, deductBalance
    ● Name classes as nouns. Ex: User, UserController
    ● Use pronounceable names. Ex: modificationTimestamp, isActive, createAndSave
    

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23. Good Functions
    ● Should be small as possible
    ● Should do just one (or multiple by context) thing
    ● Should have fewer arguments
    ● No side effects
    

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26. Try to prevent nested condition
    Bad Good
    

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27. Do we need comments?
    ● No. Your code should be self explain
    ● Only put comment if necessary
    ○ Some trade off
    ○ Deprecation warning
    ○ What point or process needs to be aware
    

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28. DRY - Don’t Repeat Yourself
    “Every piece of knowledge must have a single, unambiguous, authoritative representation within a system”
    ● Actually duplication is fine*
    ● Extract part of code that can be reused to a class or function
    

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29. KISS - Keep It Simple Stupid
    ● Code less
    ● Easy to understand, debug, and modify
    ● Complex code != smart
    

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30. YAGNI - You Aren't Gonna Need It
    ● “Maybe we need use that in the future”
    ● Only code what you need to build
    ● Avoid adding unnecessary dependencies or complexity
    ● Leads to over engineering
    

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31. Design Pattern & System Design
    ● Understanding design patterns can help us to make decision with our code
    ○ Creational pattern
    ○ Structural pattern
    ○ Behavioral pattern
    ● Understanding system design to prevent tech debt or over engineering
    ○ Monolith Design
    ○ Domain Driven Design
    ○ Microservices
    ○ Architectural Pattern
    

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32. Dealing With Legacy Code
    

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33. ● Do not judge it
    ● Understand how it runs
    ● Understand the structure & pattern
    ● Understand the business context
    ● Raise your empathy
    ● Leave better than you found it
    

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34. Do we need to refactor the bad codes?
    It depends! What is your organization’s prioritization?
    

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35. Working on new or modifying features
    ● Follow current structure with better approach
    ● Plan and communicate if you are proposing approach that might totally different with current
    structure
    ● Add unit tests or automated tests if possible
    ● Do pair programming or code review
    ● Done is better than perfect
    

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36. Clean Code is a Journey
    ● Remember, your first code must be awful. Keep practice
    ● Learn design patterns and system designs
    ● Get more insight, find mentor or developer fellows, contribute to open source
    

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37. QnA
    

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