MicroObjects - Seattle Code Camp 2018

Writing highly maintainable code is hard. Without being able to maintain the code it rots and eventually must be replaced. Some very simple constraints can produce highly maintainable code. Highly maintainable code allows quicker delivery of new features. Let's explore the practices that allow quick deliver of highly maintainable software.

Transcript

1. Feature Parity in
   25% of the Dev Hours
   With MicroObjects
   @TheQuinnGil https://QuinnGil.com
   

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2. MicroObjects
   Object Oriented Practices to the Extreme
   

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3. Quinn Gil
   Blog -- QuinnGil.com
   Twitter -- TheQuinnGil
   Github -- Fyzxs
   

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4. Primary Philosophy
   

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5. Primary Philosophy
   Single Responsibility
   

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6. Single Responsibility
   What’s its job?
   

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7. Single Responsibility
   Single Behavior
   

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8. Technical Practices…
   ● No Getters / No Setters
   ● Always Immutable
   ● No ‘new’ Inline
   ● No Primitive Obsession
   ● Encapsulate Relationships
   ● ‘if’ Only as Guard Clause
   ● ‘switch’ & ‘else’ Always Evil
   ● Composition Over Inheritance
   ● Interface Everything
   ● Isolate Their Code
   ● No Statics
   ● No nulls
   

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9. Technical Practices… Drive Single Responsibility
   ● No Getters / No Setters
   ● Always Immutable
   ● No ‘new’ Inline
   ● No Primitive Obsession
   ● Encapsulate Relationships
   ● ‘if’ Only as Guard Clause
   ● ‘switch’ & ‘else’ Always Evil
   ● Composition Over Inheritance
   ● Interface Everything
   ● No Statics
   ● No nulls
   ● Isolate Their Code
   

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10. Driving Single Responsibility
    No Getters / No Setters
    ‘if’s Only as a Guard Clause
    Isolate Their Code
    

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11. Driving Single Responsibility
    No Getters / No Setters
    

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12. No Getters / No Setters
    My Definition
    

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13. No Getters / No Setters
    class FizzBuzzBag{
    public int Input{ get; set; }
    public string Result{ get; set; }
    }
    class FizzBuzzBag:
    def __init__(self):
    self._result = None
    self._input = None
    @property
    def result(self):
    return self._result
    @result.setter
    def result(self, value):
    self._result = value
    @property
    def input(self):
    return self._input
    @input.setter
    def input(self, value):
    self._input = value
    class FizzBuzzBag{
    private int input;
    private String result;
    public String getResult(){
    return result;
    }
    public void setResult(String value){
    result = value;
    }
    public int getInput(){
    return input;
    }
    public void setInput(int value){
    input = value;
    }
    }
    class FizzBuzzBag
    attr_accessor :input
    attr_accessor :result
    end
    

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14. No Getters / No Setters
    No Way
    

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15. No Getters / No Setters
    

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16. No Getters
    Why?
    

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17. No Getters
    Behavior
    

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18. No Getters / No Setters
    

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19. No Getters / No Setters
    

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20. No Setters
    Why?
    

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21. No Setters
    Behavior
    

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22. No Setters
    Clear Usage
    

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23. No Getters / No Setters
    

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24. No Getters / No Setters
    

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25. No Getters / No Setters
    class FizzBuzzBag{
    public int Input{ get; set; }
    public string Result{ get; set; }
    }
    private void CalcFizzBuzzResult(FizzBuzzBag fb){
    var sb = new StringBuilder();
    if(ShouldIncludeFizz(fb.Input)){
    sb.Append("Fizz");
    }
    if(ShouldIncludeBuzz(fb.Input)){
    sb.Append("Buzz");
    }
    fb.Result = sb.Length != 0 ? sb.ToString() : fb.Input.ToString();
    }
    

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26. No Getters / No Setters - Encapsulated Behavior
    class FizzBuzz{
    private readonly int input;
    public FizzBuzz(int input){
    this.input = input;
    }
    public string Result(){
    var sb = new StringBuilder();
    if(ShouldIncludeFizz(input)){
    sb.Append("Fizz");
    }
    if(ShouldIncludeBuzz(input)){
    sb.Append("Buzz");
    }
    return sb.Length != 0 ? sb.ToString() : input.ToString();
    }
    }
    

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27. Driving Single Responsibility
    No Getters / No Setters
    ‘if’s Only as a Guard Clause
    Isolate Their Code
    

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28. ‘if’s Only as a Guard Clause
    Driving Single Responsibility
    

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29. ‘if’s Only as a Guard Clause
    No Way
    

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30. ‘if’s Only as a Guard Clause
    Cascading Effect
    

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31. ‘if’s Only as a Guard Clause
    Success Path
    

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32. ‘if’s Only as a Guard Clause - Success Path
    class FizzBuzz{
    private readonly int input;
    public FizzBuzz(int input){
    this.input = input;
    }
    public string Result(){
    var sb = new StringBuilder();
    if(ShouldIncludeFizz(input)){
    sb.Append("Fizz");
    }
    if(ShouldIncludeBuzz(input)){
    sb.Append("Buzz");
    }
    return sb.Length != 0
    ? sb.ToString()
    : input.ToString();
    }
    }
    

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33. ‘if’s Only as a Guard Clause - Success Path
    class FizzBuzz{
    private readonly int input;
    public FizzBuzz(int input){
    this.input = input;
    }
    public string Result(){
    var sb = new StringBuilder();
    if(ShouldIncludeFizz(input)){
    sb.Append("Fizz");
    }
    if(ShouldIncludeBuzz(input)){
    sb.Append("Buzz");
    }
    return sb.Length != 0
    ? sb.ToString()
    : input.ToString();
    }
    }
    class FizzBuzz{
    private readonly int input;
    public FizzBuzz(int input){
    this.input = input;
    }
    public string Result(){
    if(ShouldBeFizzBuzz(input)) return "FizzBuzz";
    if(ShouldBeFizz(input)) return "Fizz";
    if(ShouldBeBuzz(input)) return "Buzz";
    return input.ToString();
    }
    }
    

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34. FizzBuzz?
    

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35. Driving Single Responsibility
    No Getters / No Setters
    ‘if’s Only as a Guard Clause
    Isolate Their Code
    

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36. Driving Single Responsibility
    Isolate Their Code
    

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37. Isolate Their Code
    OOP Practices
    

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38. Isolate Their Code - OOP Practices
    class FizzBuzz{
    private readonly string json;
    public string Result(){
    JObject jObject = JObject.Parse(json);
    int input = jObject.Value("input");
    if(ShouldBeFizzBuzz(input)) return "FizzBuzz";
    if(ShouldBeFizz(input)) return "Fizz";
    if(ShouldBeBuzz(input)) return "Buzz";
    return input.ToString();
    }
    }
    

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39. Isolate Their Code
    Coupling
    

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40. Isolate Their Code
    Commonality
    

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41. Isolate Their Code
    Single Behavior
    

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42. Isolate Their Code - Single Behavior
    class FizzBuzz{
    private readonly string json;
    private readonly IParser parser;
    public string Result(){
    IParsedObject pObject = parser.Parse(json);
    int input = pObject.IntValue("input");
    if(ShouldBeFizzBuzz(input)) return "FizzBuzz";
    if(ShouldBeFizz(input)) return "Fizz";
    if(ShouldBeBuzz(input)) return "Buzz";
    return input.ToString();
    }
    }
    

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43. Isolate Their Code - Single Behavior
    class FizzBuzz{
    private readonly IFizzBuzzInput input;
    public FizzBuzz(IFizzBuzzInput input){
    this.input = input;
    }
    public string Result(){
    if(ShouldBeFizzBuzz(input)) return "FizzBuzz";
    if(ShouldBeFizz(input)) return "Fizz";
    if(ShouldBeBuzz(input)) return "Buzz";
    return input.AsString();
    }
    }
    class FizzBuzz{
    private readonly string json;
    private readonly IParser parser;
    public string Result(){
    IParsedObject pObject = parser.Parse(json);
    int input = pObject.IntValue("input");
    if(ShouldBeFizzBuzz(input)) return "FizzBuzz";
    if(ShouldBeFizz(input)) return "Fizz";
    if(ShouldBeBuzz(input)) return "Buzz";
    return input.ToString();
    }
    }
    

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44. Asymmetric Marriage
    

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45. Driving Single Responsibility
    No Getters / No Setters
    ‘if’s Only as a Guard Clause
    Isolate Their Code
    

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46. 25% of the Dev Hours
    

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47. ● No Getters / No Setters
    ● Always Immutable
    ● No ‘new’ Inline
    ● No Enum
    ● No Primitive Obsession
    ● Encapsulate Relationships
    ● ‘if’ Only as Guard Clause
    ● ‘switch’ & ‘else’ Always Evil
    ● Composition Over Inheritance
    ● Interface Everything
    ● No Public Statics
    ● No nulls
    ● Isolate Their Code
    

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49. MicroObjects
    Single Responsibility to the Extreme
    @TheQuinnGil https://QuinnGil.com
    

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