Class: OandaAPI::ResourceBase

Inherits:
Object
  • Object
show all
Defined in:
lib/oanda_api/resource_base.rb

Overview

Base class for all Resources.

Constant Summary collapse

NOT_PLURALIZED =

List of API resources that don't follow normal REST naming standards, and are not pluralized despite being collections.

[:calendar]

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(attributes = {}) ⇒ ResourceBase

Returns a new instance of ResourceBase.

Parameters:

  • attributes (Hash) (defaults to: {}) —

    collection of resource attributes. See the Oanda Developer Guide for documentation about resource attributes.



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# File 'lib/oanda_api/resource_base.rb', line 19

def initialize(attributes = {})
  initialize_attributes Utils.rubyize_keys(attributes)
  @location = attributes.location if attributes.respond_to? :location
end

Instance Attribute Details

#location ⇒ String

Returns the location header if one is returned in an API response.

Examples:

Using the location attribute

client = OandaAPI::Client::TokenClient.new :practice, token
all_transactions = client.(123).alltransactions.get
all_transactions.location # => https://fxtrade.oanda.com/transactionhistory/d3aed6823c.json.zip

Returns:

  • (String) —

    the location header if one is returned in an API response.



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# File 'lib/oanda_api/resource_base.rb', line 13

class ResourceBase
  attr_accessor :location

  # @param [Hash] attributes collection of resource attributes. See the
  #   {http://developer.oanda.com/rest-live/development-guide/ Oanda Developer Guide}
  #   for documentation about resource attributes.
  def initialize(attributes = {})
    initialize_attributes Utils.rubyize_keys(attributes)
    @location = attributes.location if attributes.respond_to? :location
  end

  # Serializes an instance as JSON.
  # @return [String] a stringified JSON representation of an instance
  def to_json(*args)
    JSON.generate @_attributes.merge(custom_attributes), *args
  end

  # Returns the class of a Resource if klass_symbol is the name
  #   of a resource, otherwise nil.
  #
  #   @example Example:
  #     ResourceBase.class_from_symbol(:transaction_history) => OandaAPI::Resource::TransactionHistory
  #     ResourceBase.class_from_symbol(:calendar_event) => OandaAPI::Resource::Labs::CalendarEvent
  #
  # @param [Symbol] resource_symbol symbolized resource name
  #
  # @return [Nil] if resource_symbol is not a Resource.
  #
  # @return [Class] if resource_symbol is identifies a Resource.
  def self.class_from_symbol(resource_symbol)
    descendant resource_symbol
  end

  # Tests whether a class is a Labs Resource.
  #
  # @param [Class] klass the class to be tested.
  #
  # @return [Boolean] True if the class is a Labs Resource.
  def self.labs_resource?(klass)
    (@lab_resources ||=[]).include? klass
  end

  # List of API resources that don't follow normal REST naming standards,
  #  and are not pluralized despite being collections.
  NOT_PLURALIZED = [:calendar]

  # Returns a pluralized version of the resource class name
  # @param [Symbol] klass_symbol
  # @return [String] the pluralized resource class name
  def self.pluralize(klass_symbol)
    NOT_PLURALIZED.include?(klass_symbol.to_sym) ? klass_symbol.to_s : OandaAPI::Utils.pluralize(klass_symbol)
  end

  private

  # @private
  # Called whenever ResourceBase class is inherited by a descendant class.
  #  Used to track descendant classes.
  #  Used to identify classes within the "::Labs::" namespace.
  def self.inherited(klass)
    ResourceBase.inherited(klass) unless self == OandaAPI::ResourceBase
    klass.to_s.match(/^(?<labs>(.*::)?Labs::)?(.*?)?(?<resource_name>(\w)+)$/) do |matched|
      resource_symbol = OandaAPI::Utils.underscore(matched[:resource_name]).to_sym
      (@descendants ||= {})[resource_symbol] = klass
      (@lab_resources ||= []) << klass if matched[:labs]
    end
  end

  # @private
  # Initializes attributes.
  #
  # @param [Hash] attributes collection of resource attributes.
  # @return [void]
  def initialize_attributes(attributes)
    @_attributes = attributes
    attributes.each do |key, value|
      send("#{key}=", value) if respond_to? key
    end
  end

  # @private
  # Provides additional attributes used in serialization.
  # @return [Hash] a hash of customized attributes for serialization
  def custom_attributes
    {}.tap { |hash| hash[:location] = location if location }
  end

  # @private
  # Returns a class name if klass_symbol is the name of a class that
  # descends from {OandaAPI::ResourceBase}, otherwise nil.
  # @param [Symbol] klass_symbol class name of a resource class
  # @return [Class]
  # @return [Nil] if klass_symbol is not a class that descends from
  #  {OandaAPI::ResourceBase}.
  def self.descendant(klass_symbol)
    (@descendants || {})[klass_symbol]
  end
end

Class Method Details

.class_from_symbol(resource_symbol) ⇒ Nil, Class

Returns the class of a Resource if klass_symbol is the name of a resource, otherwise nil.

@example Example: ResourceBase.class_from_symbol(:transaction_history) => OandaAPI::Resource::TransactionHistory ResourceBase.class_from_symbol(:calendar_event) => OandaAPI::Resource::Labs::CalendarEvent

Parameters:

  • resource_symbol (Symbol) —

    symbolized resource name

Returns:

  • (Nil) —

    if resource_symbol is not a Resource.

  • (Class) —

    if resource_symbol is identifies a Resource.



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# File 'lib/oanda_api/resource_base.rb', line 42

def self.class_from_symbol(resource_symbol)
  descendant resource_symbol
end

.labs_resource?(klass) ⇒ Boolean

Tests whether a class is a Labs Resource.

Parameters:

  • klass (Class) —

    the class to be tested.

Returns:

  • (Boolean) —

    True if the class is a Labs Resource.



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# File 'lib/oanda_api/resource_base.rb', line 51

def self.labs_resource?(klass)
  (@lab_resources ||=[]).include? klass
end

.pluralize(klass_symbol) ⇒ String

Returns a pluralized version of the resource class name

Parameters:

  • klass_symbol (Symbol)

Returns:

  • (String) —

    the pluralized resource class name



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# File 'lib/oanda_api/resource_base.rb', line 62

def self.pluralize(klass_symbol)
  NOT_PLURALIZED.include?(klass_symbol.to_sym) ? klass_symbol.to_s : OandaAPI::Utils.pluralize(klass_symbol)
end

Instance Method Details

#to_json(*args) ⇒ String

Serializes an instance as JSON.

Returns:

  • (String) —

    a stringified JSON representation of an instance



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# File 'lib/oanda_api/resource_base.rb', line 26

def to_json(*args)
  JSON.generate @_attributes.merge(custom_attributes), *args
end