Class: Sunspot::Adapters::DataAccessor

Inherits:
Object
  • Object
show all
Defined in:
lib/sunspot/adapters.rb

Overview

Subclasses of the DataAccessor class take care of retrieving instances of the adapted class from (usually persistent) storage. Subclasses must implement the #load method, which takes an id (the value returned by InstanceAdapter#id, as a string), and returns the instance referenced by that ID. Optionally, it can also override the #load_all method, which takes an array of IDs and returns an array of instances in the order given. #load_all need only be implemented if it can be done more efficiently than simply iterating over the IDs and calling #load on each individually.

Example

class FileAccessor < Sunspot::Adapters::InstanceAdapter
  def load(id)
    @clazz.open(id)
  end
end

Sunspot::Adapters::DataAccessor.register(FileAccessor, File)

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(clazz) ⇒ DataAccessor

:nodoc:



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# File 'lib/sunspot/adapters.rb', line 215

def initialize(clazz) #:nodoc:
  @clazz = clazz
  @inherited_attributes = []
end

Instance Attribute Details

#clazz ⇒ Object (readonly)

Returns the value of attribute clazz.



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# File 'lib/sunspot/adapters.rb', line 213

def clazz
  @clazz
end

#inherited_attributes ⇒ Object

Attributes that should be passed to other adapted subclasses



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# File 'lib/sunspot/adapters.rb', line 212

def inherited_attributes
  @inherited_attributes
end

Class Method Details

.create(clazz) ⇒ Object

Create a DataAccessor for the given class, searching registered adapters for the best match. See InstanceAdapter#adapt for discussion of inheritance.

Parameters

clazz<Class>

Class to create DataAccessor for

Returns

DataAccessor

DataAccessor implementation which provides access to given class



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# File 'lib/sunspot/adapters.rb', line 250

def create(clazz) #:nodoc:
  self.for(clazz).new(clazz)
end

.for(clazz) ⇒ Object

Find the best DataAccessor implementation that adapts the given class. Starting with the class and then moving up the ancestor chain, looks for registered DataAccessor implementations.

Parameters

clazz<Class>

The class to find a DataAccessor for

Returns

Class

Implementation of DataAccessor

Raises

Sunspot::NoAdapterError

If no data accessor exists for the given class

Raises:



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# File 'lib/sunspot/adapters.rb', line 287

def for(clazz) #:nodoc:
  accessor = registered_accessor_for(clazz) || registered_accessor_for_ancestors_of(clazz)
  return accessor if accessor
  raise(Sunspot::NoAdapterError,
        "No data accessor is configured for #{clazz.name} or its superclasses. See the documentation for Sunspot::Adapters")
end

.register(data_accessor, *classes) ⇒ Object

Register data accessor for a set of classes. When searching for an accessor for a given class, Sunspot starts with the class, and then searches for registered adapters up the class’s ancestor chain.

Parameters

data_accessor<Class>

The data accessor class to register

classes…<Class>

One or more classes that this data accessor provides access to



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# File 'lib/sunspot/adapters.rb', line 265

def register(data_accessor, *classes)
  classes.each do |clazz|
    data_accessors[clazz.name.to_sym] = data_accessor
  end
end

.registered_accessor_for(clazz) ⇒ Object

Returns the directly-registered accessor for the specified class, if one exists, without searching the class’s ancestors.

Parameters

clazz<Class>

The model class to be checked for the registered

data accessor

Returns

Class

Subclass of DataAccessor, or nil if none found



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# File 'lib/sunspot/adapters.rb', line 306

def registered_accessor_for(clazz)
  return nil if clazz.name.nil? || clazz.name.empty?
  data_accessors[clazz.name.to_sym]
end

Instance Method Details

#load_all(ids) ⇒ Object

Subclasses can override this class to provide more efficient bulk loading of instances. Instances must be returned in the same order that the IDs were given.

Parameters

ids<Array>

collection of IDs

Returns

Array

collection of instances, in order of IDs given



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# File 'lib/sunspot/adapters.rb', line 232

def load_all(ids)
  ids.map { |id| self.load(id) }
end