v3: refactor model rendering

lib/travis/api/v3/renderer.rb

@@ -6,19 +6,6 @@ module Travis::API::V3
     extend ConstantResolver
     extend self
 
-    def format_date(date)
-      date && date.strftime('%Y-%m-%dT%H:%M:%SZ')
-    end
-
-    def get_attributes(object, *attributes, **defaults)
-      attributes.map { |a| [a, get_attribute(object, a, **defaults)] }.to_h
-    end
-
-    def get_attribute(object, attribute, **defaults)
-      value = object.public_send(attribute)
-      value.nil? ? defaults[attribute] : value
-    end
-
     def clear(**args)
       args.select { |key, value| !value.nil? }
     end

lib/travis/api/v3/renderer/model_renderer.rb

@@ -0,0 +1,65 @@
+module Travis::API::V3
+  class Renderer::ModelRenderer
+    PRIMITIVE = [String, Symbol, Numeric, true, false, nil]
+    private_constant :PRIMITIVE
+
+    def self.type(type = nil)
+      @type = type if type
+      @type = name[/[^:]+$/].underscore.to_sym unless defined? @type # allows setting type to nil
+      @type
+    end
+
+    def self.representation(name, *fields)
+      fields.each { |field| class_eval "def #{field}; @model.#{field}; end" unless method_defined?(field) }
+      representations[name] = fields
+    end
+
+    def self.representations
+      @representations ||= {}
+    end
+
+    def self.render(model, representation = :standard, **options)
+      new(model, **options).render(representation)
+    end
+
+    attr_reader :model, :options, :script_name
+    attr_writer :href
+
+    def initialize(model, script_name: nil, **options)
+      @model       = model
+      @options     = options
+      @script_name = script_name
+    end
+
+    def href
+      return @href if defined? @href # allows setting href to nil
+      return unless self.class.type and model.respond_to? :id and model.id
+      @href = Renderer.href(self.class.type, script_name: script_name, id: model.id)
+    end
+
+    def render(representation)
+      result         = {}
+      result[:@type] = self.class.type if self.class.type
+      result[:@href] = href if href
+      fields         = self.class.representations.fetch(representation)
+
+      fields.each { |field| result[field] = render_value(send(field)) }
+      result
+    end
+
+    def render_model(model, type: model.class.name.to_sym, mode: :minimal, **options)
+      Renderer[type].render(model, mode, script_name: script_name, **options)
+    end
+
+    def render_value(value)
+      case value
+      when Hash          then value.map { |k, v| [k, render_value(v)] }.to_h
+      when Array         then value.map { |v   | render_value(v)      }
+      when *PRIMITIVE    then value
+      when Time          then value.strftime('%Y-%m-%dT%H:%M:%SZ')
+      when Travis::Model then render_model(value)
+      else raise ArgumentError, 'cannot render %p (%p)' % [value.class, value]
+      end
+    end
+  end
+end

lib/travis/api/v3/renderer/organization.rb

@@ -1,18 +1,8 @@
+require 'travis/api/v3/renderer/model_renderer'
+
 module Travis::API::V3
-  module Renderer::Organization
-    DIRECT_ATTRIBUTES = %i[id login name github_id]
-    extend self
-
-    def render(organization, script_name: nil, **)
-      {
-        :@type => 'organization'.freeze,
-        :@href => Renderer.href(:organization, id: organization.id, script_name: script_name),
-        **direct_attributes(organization)
-      }
-    end
-
-    def direct_attributes(repository)
-      DIRECT_ATTRIBUTES.map { |a| [a, repository.public_send(a)] }.to_h
-    end
+  class Renderer::Organization < Renderer::ModelRenderer
+    representation(:minimal,  :id, :login)
+    representation(:standard, :id, :login, :name, :github_id)
   end
 end

lib/travis/api/v3/renderer/repository.rb

@@ -1,38 +1,36 @@
+require 'travis/api/v3/renderer/model_renderer'
+
 module Travis::API::V3
-  module Renderer::Repository
-    DIRECT_ATTRIBUTES = %i[id name slug description github_language private active default_branch]
-    DEFAULTS          = { active: false, default_branch: 'master' }
-    extend self
+  class Renderer::Repository < Renderer::ModelRenderer
+    representation(:minimal,  :id, :slug)
+    representation(:standard, :id, :name, :slug, :description, :github_language, :active, :private, :default_branch, :owner, :last_build)
 
-    def render(repository, script_name: nil, **)
+    def default_branch
+      model.default_branch || 'master'.freeze
+    end
+
+    def active
+      !!model.active
+    end
+
+    def owner
       {
-        :@type => 'repository'.freeze,
-        :@href => Renderer.href(:repository, id: repository.id, script_name: script_name),
-        **Renderer.get_attributes(repository, *DIRECT_ATTRIBUTES, **DEFAULTS), **nested_resources(repository)
+        :@type        => model.owner_type && model.owner_type.downcase,
+        :id           => model.owner_id,
+        :login        => model.owner_name
       }
     end
 
-    def nested_resources(repository)
-      {
-        owner: {
-          :@type        => repository.owner_type && repository.owner_type.downcase,
-          :id           => repository.owner_id,
-          :login        => repository.owner_name
-        },
-        last_build: last_build(repository)
-      }
-    end
-
-    def last_build(repository)
-      return nil unless repository.last_build_id
+    def last_build
+      return nil unless model.last_build_id
       {
         :@type        => 'build'.freeze,
-        :id           => repository.last_build_id,
-        :number       => repository.last_build_number,
-        :state        => repository.last_build_state.to_s,
-        :duration     => repository.last_build_duration,
-        :started_at   => Renderer.format_date(repository.last_build_started_at),
-        :finished_at  => Renderer.format_date(repository.last_build_finished_at),
+        :id           => model.last_build_id,
+        :number       => model.last_build_number,
+        :state        => model.last_build_state.to_s,
+        :duration     => model.last_build_duration,
+        :started_at   => model.last_build_started_at,
+        :finished_at  => model.last_build_finished_at,
       }
     end
   end