Class: IntrospectiveGrape::API

Inherits:
Grape::API::Instance
  • Object
show all
Extended by:
CreateHelpers, Doc, Filters, Helpers, SnakeParams, Traversal
Defined in:
lib/introspective_grape/api.rb

Constant Summary collapse

PLURAL_REFLECTIONS = 
[ ActiveRecord::Reflection::HasManyReflection, ActiveRecord::Reflection::HasManyReflection].freeze
Pg2Ruby =

mapping of activerecord/postgres ‘type’s to ruby data classes, where they differ

{ datetime: DateTime }.freeze

Constants included from Helpers

Helpers::API_ACTIONS

Class Method Summary collapse

Methods included from Helpers

authentication_method, authentication_method=, default_includes, exclude_actions, include_actions, paginate, pagination, skip_presence_validations, whitelist

Methods included from CreateHelpers

add_new_records_to_root_record, create_new_record

Methods included from Filters

apply_filter_params, apply_simple_filter, custom_filter, custom_filters, declare_filter_params, default_sort, filter_on, filters, identifier_filter, simple_filters, timestamp_filter

Methods included from Traversal

find_leaf, find_leaves, verify_record_found, verify_records_found

Methods included from Doc

create_documentation, destroy_documentation, index_documentation, show_documentation, update_documentation

Methods included from SnakeParams

snake_params_before_validation

Class Method Details

.add_destroy_param(dsl, model, reflection) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 410

def add_destroy_param(dsl,model,reflection)
  raise "#{model} does not accept nested attributes for #{reflection}" if !model.nested_attributes_options[reflection.to_sym]
  # If destruction is allowed append the _destroy field
  if model.nested_attributes_options[reflection.to_sym][:allow_destroy]
    dsl.optional '_destroy', type: Integer
  end
end

.build_nested_attributes(routes, hash) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 292

def build_nested_attributes(routes,hash)
  # Recursively re-express the flat attributes hash from nested routes as nested
  # attributes that can be used to perform an update on the root model.

  # do nothing if the params are already nested.
  return {} if routes.blank? || hash[routes.first.param]

  route  = routes.shift
  # change 'x_id' to 'x_attributes': { id: id, y_attributes: {} }
  id      = hash.delete route.key
  attributes = id ? { id: id } : {}

  attributes.merge!( hash ) if routes.blank? # assign param values to the last reference

  if route.many? # nest it in an array if it is a has_many association
    { route.param => [attributes.merge( build_nested_attributes(routes, hash) )] }
  else
    { route.param => attributes.merge( build_nested_attributes(routes, hash) ) }
  end
end

.build_routes(routes, model, reflection_name = nil) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 270

def build_routes(routes, model, reflection_name=nil)
  routes = routes.clone
  # routes: the existing routes array passed from the parent
  # model:  the model being manipulated in this leaf
  # reflection_name: the association name from the original strong_params declaration
  #
  # Constructs an array representation of the route's models and their associations,
  # a /root/:rootId/branch/:branchId/leaf/:leafId path would have flat array like
  # [root,branch,leaf] representing the path structure and its models, used to
  # manipulate ActiveRecord relationships and params hashes and so on.
  parent_model = routes.last.try(:model)
  return routes if model == parent_model

  name       = reflection_name || model.name.underscore
  reflection = parent_model.try(:reflections).try(:fetch,reflection_name)
  many       = parent_model && PLURAL_REFLECTIONS.include?( reflection.class ) ? true : false
  swaggerKey = IntrospectiveGrape.config.camelize_parameters ? "#{name.singularize.camelize(:lower)}Id" : "#{name.singularize}_id"

  routes.push OpenStruct.new(klass: self, name: name, param: "#{name}_attributes", model: model, many?: many, key: "#{name.singularize}_id".to_sym, swaggerKey: swaggerKey, reflection: reflection)
end

.convert_nested_params_hash(dsl, routes) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 129

def convert_nested_params_hash(dsl, routes)
  root  = routes.first
  klass = root.klass
  dsl.after_validation do
    # After Grape validates its parameters:
    # 1) Find the root model instance for the API if its passed (implicitly either
    #    an update/destroy on the root node or it's a nested route
    # 2) For nested endpoints convert the params hash into Rails-compliant nested
    #    attributes, to be passed to the root instance for update. This keeps
    #    behavior consistent between bulk and single record updates.

    if params[root.key]
      @model = root.model.includes( klass.default_includes(root.model) ).find(params[root.key])
    end

    if routes.size > 1
      nested_attributes = klass.build_nested_attributes(routes[1..-1], params.except(root.key,:api_key) )
      @params.merge!( nested_attributes ) if nested_attributes.kind_of?(Hash)
    end
  end
end

.define_create(dsl, routes, model, api_params) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 222

def define_create(dsl, routes, model, api_params)
  name  = routes.last.name.singularize
  klass = routes.first.klass
  dsl.desc "create a #{name}" do
    detail klass.create_documentation || "creates a new #{name} record"
  end
  dsl.params do
    klass.generate_params(self, :create, model, api_params, true)
  end
  dsl.post do
    representation = @model ? klass.add_new_records_to_root_record(self, routes, params, @model) : klass.create_new_record(self, routes, params)
    present representation, with: "#{klass}::#{model}Entity".constantize
  end
end

.define_destroy(dsl, routes, _model, _api_params) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 257

def define_destroy(dsl, routes, _model, _api_params)
  klass = routes.first.klass
  name = routes.last.name.singularize
  dsl.desc "destroy a #{name}" do
    detail klass.destroy_documentation || "destroys the details of a #{name}"
  end
  dsl.delete ":#{routes.last.swaggerKey}" do
    authorize @model, :destroy?
    present status: (klass.find_leaf(routes, @model, params).destroy ? true : false)
  end
end

.define_endpoints(routes, api_params) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 158

def define_endpoints(routes,api_params)
  # De-reference these as local variables from their class scope, or when we make
  # calls to the API they will be whatever they were last set to by the recursive
  # calls to "nest_routes".
  routes     = routes.clone
  api_params = api_params.clone

  model     = routes.last.model || return

  # We define the param keys for ID fields in camelcase for swagger's URL substitution,
  # they'll come back in snake case in the params hash, the API as a whole is agnostic:
  namespace = routes[0..-2].map{|p| "#{p.name.pluralize}/:#{p.swaggerKey}/" }.join + routes.last.name.pluralize

  resource namespace do
    convert_nested_params_hash(self, routes)
    define_restful_api(self, routes, model, api_params)
  end
end

.define_index(dsl, routes, model, api_params) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 177

def define_index(dsl, routes, model, api_params)
  include Grape::Kaminari
  root  = routes.first
  klass = routes.first.klass
  name  = routes.last.name.pluralize
  simple_filters(klass, model, api_params)

  dsl.desc "list #{name}" do
    detail klass.index_documentation || "returns list of all #{name}"
  end
  dsl.params do
    klass.declare_filter_params(self, klass, model, api_params)
  end
  if klass.pagination
    paginate per_page: klass.pagination[:per_page]||25, max_per_page: klass.pagination[:max_per_page], offset: klass.pagination[:offset]||0
  end
  dsl.get '/' do
    # Invoke the policy for the action, defined in the policy classes for the model:
    authorize root.model.new, :index?

    # Nested route indexes need to be scoped by the API's top level policy class:
    records = policy_scope( root.model.includes(klass.default_includes(root.model)) )

    records = klass.apply_filter_params(klass, model, api_params, params, records)

    records = records.map{|r| klass.find_leaves( routes, r, params ) }.flatten.compact.uniq

    # paginate the records using Kaminari
    records = paginate(Kaminari.paginate_array(records)) if klass.pagination
    present records, with: "#{klass}::#{model}Entity".constantize
  end
end

.define_restful_api(dsl, routes, model, api_params) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 151

def define_restful_api(dsl, routes, model, api_params)
  # declare index, show, update, create, and destroy methods:
  API_ACTIONS.each do |action|
    send("define_#{action}", dsl, routes, model, api_params) unless exclude_actions(model).include?(action)
  end
end

.define_routes(routes, api_params) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 107

def define_routes(routes, api_params)
  define_endpoints(routes, api_params)
  # recursively define endpoints
  model = routes.last.model || return

  api_params.select{|a| a.kind_of?(Hash) }.each do |nested|
    # Recursively add RESTful nested routes for every nested model:
    nested.each do |r,fields|
      # Look at model.reflections to find the association's class name:
      reflection_name = r.to_s.sub(/_attributes$/,'')
      begin
        relation = model.reflections[reflection_name].class_name.constantize
      rescue
        Rails.logger.fatal "Can't find associated model for #{r} on #{model}"
      end

      next_routes = build_routes(routes, relation, reflection_name)
      define_routes(next_routes, fields)
    end
  end
end

.define_show(dsl, routes, model, _api_params) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 210

def define_show(dsl, routes, model, _api_params)
  name = routes.last.name.singularize
  klass = routes.first.klass
  dsl.desc "retrieve a #{name}" do
    detail klass.show_documentation || "returns details on a #{name}"
  end
  dsl.get ":#{routes.last.swaggerKey}" do
    authorize @model, :show?
    present klass.find_leaf(routes, @model, params), with: "#{klass}::#{model}Entity".constantize
  end
end

.define_update(dsl, routes, model, api_params) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 237

def define_update(dsl, routes, model, api_params)
  klass = routes.first.klass
  name = routes.last.name.singularize
  dsl.desc "update a #{name}" do
    detail klass.update_documentation || "updates the details of a #{name}"
  end
  dsl.params do
    klass.generate_params(self, :update, model, api_params, true)
  end
  dsl.put ":#{routes.last.swaggerKey}" do
    authorize @model, :update?

    @model.update_attributes!( safe_params(params).permit(klass.whitelist) )
   
    default_includes = routes.first.klass.default_includes(routes.first.model)

    present klass.find_leaf(routes, @model.class.includes(default_includes).find(@model.id), params), with: "#{klass}::#{model}Entity".constantize
  end
end

.generate_nested_params(dsl, action, model, fields) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 348

def generate_nested_params(dsl,action,model,fields)
  klass = self
  fields.each do |r,v|
    # Look at model.reflections to find the association's class name:
    reflection = r.to_s.sub(/_attributes$/,'') # the reflection name
    relation = begin model.reflections[reflection].class_name.constantize rescue model end

    if is_file_attachment?(model,r)
      # Handle Carrierwave file upload fields
      s = [:filename, :type, :name, :tempfile, :head]-v
      if s.present?
        Rails.logger.warn "Missing required file upload parameters #{s} for uploader field #{r}"
      end
    elsif PLURAL_REFLECTIONS.include?( model.reflections[reflection].class )
      # In case you need a refresher on how these work:
      # http://api.rubyonrails.org/classes/ActiveRecord/NestedAttributes/ClassMethods.html
      dsl.optional r, type: Array do |dl|
        klass.generate_params(dl,action,relation,v)
        klass.add_destroy_param(dl,model,reflection) unless action==:create
      end
    else
      # TODO: handle any remaining correctly. Presently defaults to a Hash
      # http://www.rubydoc.info/github/rails/rails/ActiveRecord/Reflection
      # ThroughReflection, HasOneReflection,
      # HasAndBelongsToManyReflection, BelongsToReflection
      dsl.optional r, type: Hash do |dl|
        klass.generate_params(dl,action,relation,v)
        klass.add_destroy_param(dl,model,reflection) unless action==:create
      end
    end
  end
end

.generate_params(dsl, action, model, fields, is_root_endpoint = false) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 315

def generate_params(dsl, action, model, fields, is_root_endpoint=false)
  # We'll be doing a recursive walk (to handle nested attributes) down the
  # whitelisted params, generating the Grape param definitions by introspecting
  # on the model and its associations.
  raise "Invalid action: #{action}" unless [:update, :create].include?(action)
  # dsl   : The Grape::Validations::ParamsScope object
  # action: create or update
  # model : The ActiveRecord model class
  # fields: The whitelisted data structure for Rails' strong params, from which we
  #         infer Grape's parameters

  # skip the ID param at the root level endpoint, so we don't duplicate the URL parameter (api/v#/model/modelId)
  fields -= [:id] if is_root_endpoint

  fields.each do |field|
    if field.kind_of?(Hash)
      generate_nested_params(dsl,action,model,field)
    elsif (action==:create && param_required?(model,field) )
      # All params are optional on an update, only require them during creation.
      # Updating a record with new child models will have to rely on ActiveRecord
      # validations:
      dsl.requires field, { type: param_type(model,field) }.merge( validations(model, field) )
    else
      #dsl.optional field, *options
      dsl.optional field, { type: param_type(model,field) }.merge( validations(model, field) )
    end
  end
end

.inherited(child) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 55

def inherited(child)
  super(child)
  child.before do
    # Ensure that a user is logged in.
    self.send(IntrospectiveGrape::API.authentication_method(self))
  end

  child.snake_params_before_validation if IntrospectiveGrape.config.camelize_parameters
end

.is_file_attachment?(model, field) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/introspective_grape/api.rb', line 381

def is_file_attachment?(model,field)
  model.respond_to?(:uploaders) && model.uploaders[field.to_sym] || # carrierwave
    (model.respond_to?(:attachment_definitions) && model.attachment_definitions[field.to_sym]) ||
    defined?(Paperclip::Attachment) && model.send(:new).try(field).kind_of?(Paperclip::Attachment)
end

.param_required?(model, f) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/introspective_grape/api.rb', line 401

def param_required?(model,f)
  # Detect if the field is a required field for the create action
  return false if skip_presence_validations.include?(f)

  validated_field = f =~ /_id/ ? f.to_s.sub(/_id\z/,'').to_sym : f.to_sym

  model.validators_on(validated_field).any? {|v| v.kind_of? ActiveRecord::Validations::PresenceValidator }
end

.param_type(model, f) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 387

def param_type(model,f)
  # Translate from the AR type to the GrapeParam types
  f       = f.to_s
  db_type = (model.try(:columns_hash)||{})[f].try(:type)

  # Check if it's a file attachment, look for an override class from the model,
  # check Pg2Ruby, use the database type, or fail over to a String:
  ( is_file_attachment?(model,f) && Rack::Multipart::UploadedFile ) ||
    (model.try(:grape_param_types)||{}).with_indifferent_access[f]  ||
    Pg2Ruby[db_type]                                                ||
    begin db_type.to_s.camelize.constantize rescue nil end          ||
    String
end

.restful(model, strong_params = [], routes = []) ⇒ Object

We will probably need before and after hooks eventually, but haven’t yet… api_actions.each do |a|

define_method "before_#{a}_hook" do |model,params| ; end
define_method "after_#{a}_hook" do |model,params| ; end

end



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# File 'lib/introspective_grape/api.rb', line 71

def restful(model, strong_params=[], routes=[])
  if model.respond_to?(:attribute_param_types)
    raise IntrospectiveGrapeError.new("#{model.name}'s attribute_param_types class method needs to be changed to grape_param_types")
  end
  # Recursively define endpoints for the model and any nested models.
  #
  # model: the model class for the API
  # whitelist: a list of fields in Rail's strong params structure, also used to
  #            generate grape's permitted params.
  # routes: An array of OpenStruct representations of a nested route's ancestors
  #

  # Defining the api will break pending migrations during db:migrate, so bail:
  begin ActiveRecord::Migration.check_pending! rescue return end

  # normalize the whitelist to symbols
  strong_params.map!{|f| f.kind_of?(String) ? f.to_sym : f }
  # default to a flat representation of the model's attributes if left unspecified
  strong_params = strong_params.blank? ? model.attribute_names.map(&:to_sym)-[:id, :updated_at, :created_at] : strong_params

  # The strong params will be the same for all routes, differing from the Grape params
  # when routes are nested
  whitelist = whitelist( strong_params )

  # As routes are nested keep track of the routes, we are preventing siblings from
  # appending to the routes array here:
  routes = build_routes(routes, model)
  define_routes(routes, whitelist)

  # Top level declaration of the Grape::API namespace for the resource:
  resource routes.first.name.pluralize do
    # yield to append additional routes under the root namespace
    yield if block_given?
  end
end

.validations(model, field) ⇒ Object 



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# File 'lib/introspective_grape/api.rb', line 344

def validations(model, field)
  (model.try(:grape_validations) || {}).with_indifferent_access[field] || {}
end