Class: PackAPI::Types::AggregateType

Inherits:
BaseType
  • Object
show all
Defined in:
lib/pack_api/types/aggregate_type.rb

Overview

Define a type that blends attributes from multiple resources into a single data structure. For each kind of input resource, pass a block to the ‘combine_attributes` method, wherein are enumerated the attributes in the output data structure which originate from that input resource.

Example:

class MyAggregateType < PackAPI::Types::AggregateType

combine_attributes from: :resource_one do
  attribute :id, Types::String
  attribute :name, Types::String
end
combine_attributes from: :resource_two do
  attribute :description, Types::String
  attribute :created_at, Types::Time
end

end

This will create a type with attributes ‘id`, `name`, `description`, and `created_at`, where:

- `id` and `name` come from `resource_one`
- `description` and `created_at` come from `resource_two`

For each input resource, helper methods must be defined to enable the CRUD operations:

- query_<resource>s(**params) - returns a hash of resources, indexed by their IDs
- get_<resource>(id) - returns a single resource, identified by its ID
- create_<resource>(params) - creates a new resource and returns it
- update_<resource>(id, params) - updates an existing resource and returns it
- delete_<resource>(id)

For example, for the above example, you would need to define:

- query_resource_ones
- get_resource_one
- create_resource_one
- update_resource_one
- delete_resource_one

@note: There are 2 kinds of resources:

- primary resources
- secondary resources

The first resource drawn from via ‘combine_attributes` is considered the primary resource.

Defined Under Namespace

Classes: AttributeBlender

Class Method Summary collapse

Methods inherited from BaseType

filterable_attributes, #merge, optional_attribute, optional_attributes, #to_data

Class Method Details

.attribute(name, type = Undefined, &block) ⇒ Object 



57
58
59
60
 
# File 'lib/pack_api/types/aggregate_type.rb', line 57

def attribute(name, type = Undefined, &block)
  super
  @next_attribute_list << name if @next_attribute_list
end

.combine_attributes(from:, &block) ⇒ Object 



62
63
64
65
66
67
 
# File 'lib/pack_api/types/aggregate_type.rb', line 62

def combine_attributes(from:, &block)
  @next_attribute_list = []
  block.call
  @attribute_sources[from] = @next_attribute_list
  @next_attribute_list = nil
end

.create(params) ⇒ Object 



81
82
83
 
# File 'lib/pack_api/types/aggregate_type.rb', line 81

def create(params)
  new(attribute_blender.create(params))
end

.delete(id) ⇒ Object 



85
86
87
 
# File 'lib/pack_api/types/aggregate_type.rb', line 85

def delete(id)
  attribute_blender.delete(id)
end

.get(id) ⇒ Object 



73
74
75
 
# File 'lib/pack_api/types/aggregate_type.rb', line 73

def get(id)
  new(attribute_blender.get(id))
end

.inherited(subclass) ⇒ Object 



51
52
53
54
55
 
# File 'lib/pack_api/types/aggregate_type.rb', line 51

def inherited(subclass)
  subclass.instance_variable_set(:@attribute_sources, {})
  subclass.instance_variable_set(:@next_attribute_list, nil)
  super
end

.query(**params) ⇒ Object 



69
70
71
 
# File 'lib/pack_api/types/aggregate_type.rb', line 69

def query(**params)
  attribute_blender.query(**params).map { new(it) }
end

.update(id, params) ⇒ Object 



77
78
79
 
# File 'lib/pack_api/types/aggregate_type.rb', line 77

def update(id, params)
  new(attribute_blender.update(id, params))
end