Class: KeyVortex::Limitation

Inherits:
Object
  • Object
show all
Defined in:
lib/key_vortex/limitation.rb

Overview

Represents a collection of constraints which apply to a given class. While these can be constructed directly, the intended mechanism for applying these to a record is through Record.field.

Two independent concepts which commonly use the same terminology exist in this project. Consider the term “allows”, is that referring to what values are allowed or what constraints are allowed? To help navigate these two concepts, the following terminology convention is used throughout this codebase:

  • Encompass/Within: Used when comparing limitations and constraints to each other

  • Accepts/Rejects: Used when determining if a value is valid for constraints

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(type, *constraints) ⇒ Limitation

Returns a new instance of Limitation.

Parameters:

  • type (Class)
  • constraints (KeyValue::Constraint) 


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# File 'lib/key_vortex/limitation.rb', line 25

def initialize(type, *constraints)
  @type = type
  @constraints = []
  add_constraint(*constraints)
end

Instance Attribute Details

#constraints ⇒ Array (readonly)

Returns The constraints which apply to this class.

Returns:

  • (Array) —

    The constraints which apply to this class.



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# File 'lib/key_vortex/limitation.rb', line 21

def constraints
  @constraints
end

#type ⇒ Class (readonly)

Returns The class these constraints applies to.

Returns:

  • (Class) —

    The class these constraints applies to.



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# File 'lib/key_vortex/limitation.rb', line 18

def type
  @type
end

Instance Method Details

#accepts?(value) ⇒ Boolean

Determine if a given value meets all of the constraints.

Parameters:

Returns:

  • (Boolean) 


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# File 'lib/key_vortex/limitation.rb', line 59

def accepts?(value)
  value.is_a?(type) && @constraints.all? { |constraint| constraint.accepts?(value) }
end

#add_constraint(*constraints) ⇒ Object

Add constraints to this limitation. It is also possible to do this through the constructor, but it is sometimes easier to do it one at a time.

Parameters:



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# File 'lib/key_vortex/limitation.rb', line 35

def add_constraint(*constraints)
  constraints.each do |constraint|
    unless constraint.is_a?(KeyVortex::Constraint::Base)
      raise KeyVortex::Error,
            "Not a constraint: #{constraint.class}"
    end
  end

  @constraints += constraints
end

#enable_json_additions ⇒ Object

Ensure that JSON additions for #type are loaded in case the record needs to be serialized.



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# File 'lib/key_vortex/limitation.rb', line 65

def enable_json_additions
  path = JSON_ADDITIONS[@type.class.name]
  require path if path
end

#to_s ⇒ String

Return information about this limitation. The information will be formatted as follows:

Limitation: String
  minimum: 10
  maximum: 100

Returns:

  • (String) 


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# File 'lib/key_vortex/limitation.rb', line 76

def to_s
  "Limitation: #{@type}\n\t#{@constraints.join('\n\t')}"
end

#within?(limitation) ⇒ Boolean

Determine if any of the constraints in the provided limitation exceed this limitation’s constraints.

Parameters:

Returns:

  • (Boolean) 


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# File 'lib/key_vortex/limitation.rb', line 50

def within?(limitation)
  limitation.constraints.all? do |constraint|
    within_constraint?(constraint)
  end
end