Extracting object from .load_instance_from_solr

Gemfile

@@ -7,6 +7,7 @@ gemspec
 group :development, :test do
   gem 'simplecov', :platforms => [:mri_19]#, :mri_20]
   gem 'simplecov-rcov', :platforms => [:mri_19]#, :mri_20]
+  gem 'debugger', :platforms => [:mri_19, :mri_20]
 end
 
 gem 'jruby-openssl', :platform=> :jruby

lib/active_fedora.rb

@@ -67,6 +67,7 @@ class RecordNotSaved < RuntimeError; end # :nodoc:
     autoload :DatastreamCollections
     autoload :Predicates
     autoload :Validations
+    autoload :SolrInstanceLoader
   end
 
 

lib/active_fedora/indexing.rb

@@ -4,8 +4,8 @@ module Indexing
 
     # Return a Hash representation of this object where keys in the hash are appropriate Solr field names.
     # @param [Hash] solr_doc (optional) Hash to insert the fields into
-    # @param [Hash] opts (optional) 
-    # If opts[:model_only] == true, the base object metadata and the RELS-EXT datastream will be omitted.  This is mainly to support shelver, which calls .to_solr for each model an object subscribes to. 
+    # @param [Hash] opts (optional)
+    # If opts[:model_only] == true, the base object metadata and the RELS-EXT datastream will be omitted.  This is mainly to support shelver, which calls .to_solr for each model an object subscribes to.
     def to_solr(solr_doc = Hash.new, opts={})
       unless opts[:model_only]
         c_time = create_date
@@ -43,7 +43,7 @@ def solrize_profile(solr_doc = Hash.new) # :nodoc:
       self.datastreams.each_pair { |dsid,ds| profile_hash['datastreams'][dsid] = ds.solrize_profile }
       solr_doc[self.class.profile_solr_name] = profile_hash.to_json
     end
-    
+
     # Serialize the datastream's RDF relationships to solr
     # @param [Hash] solr_doc @deafult an empty Hash
     def solrize_relationships(solr_doc = Hash.new)
@@ -58,7 +58,7 @@ def solrize_relationships(solr_doc = Hash.new)
 
     # Updates Solr index with self.
     def update_index
-      if defined?( Solrizer::Fedora::Solrizer ) 
+      if defined?( Solrizer::Fedora::Solrizer )
         #logger.info("Trying to solrize pid: #{pid}")
         solrizer = Solrizer::Fedora::Solrizer.new
         solrizer.solrize( self )
@@ -70,63 +70,32 @@ def update_index
 
 
     module ClassMethods
-      # This method can be used instead of ActiveFedora::Model::ClassMethods.find.  
+      # This method can be used instead of ActiveFedora::Model::ClassMethods.find.
       # It works similarly except it populates an object from Solr instead of Fedora.
       # It is most useful for objects used in read-only displays in order to speed up loading time.  If only
       # a pid is passed in it will query solr for a corresponding solr document and then use it
       # to populate this object.
-      # 
+      #
       # If a value is passed in for optional parameter solr_doc it will not query solr again and just use the
       # one passed to populate the object.
       #
       # It will anything stored within solr such as metadata and relationships.  Non-metadata datastreams will not
       # be loaded and if needed you should use find instead.
       def load_instance_from_solr(pid,solr_doc=nil)
-        if solr_doc.nil?
-          result = find_with_conditions(:id=>pid)
-          raise ActiveFedora::ObjectNotFoundError, "Object #{pid} not found in solr" if result.empty?
-          solr_doc = result.first
-          #double check pid and id in record match
-          raise ActiveFedora::ObjectNotFoundError, "Object #{pid} not found in Solr" unless !result.nil? && !solr_doc.nil? && pid == solr_doc[SOLR_DOCUMENT_ID]
-        else
-          raise "Solr document record id and pid do not match" unless pid == solr_doc[SOLR_DOCUMENT_ID]
-        end
-        klass = if class_str = solr_doc[ActiveFedora::SolrService.solr_name('has_model', :symbol)]
-          ActiveFedora::SolrService.class_from_solr_document(solr_doc)
-        else
-          ActiveFedora::Base
-        end
-
-        profile_json = Array(solr_doc[ActiveFedora::Base.profile_solr_name]).first
-        unless profile_json.present?
-          raise ActiveFedora::ObjectNotFoundError, "Object #{pid} does not contain a solrized profile"
-        end
-        profile_hash = ActiveSupport::JSON.decode(profile_json)
-        obj = klass.allocate.init_with(SolrDigitalObject.new(solr_doc, profile_hash, klass))
-        #set by default to load any dependent relationship objects from solr as well
-        #need to call rels_ext once so it exists when iterating over datastreams
-        obj.rels_ext
-        obj.datastreams.each_value do |ds|
-          if ds.respond_to?(:profile_from_hash) and (ds_prof = profile_hash['datastreams'][ds.dsid])
-            ds.profile_from_hash(ds_prof)
-          end
-          ds.from_solr(solr_doc) if ds.respond_to?(:from_solr)
-        end
-        obj.inner_object.freeze
-        obj
+        SolrInstanceLoader.new(self, pid, solr_doc).object
       end
-      
-      # Using the fedora search (not solr), get every object and reindex it. 
+
+      # Using the fedora search (not solr), get every object and reindex it.
       def reindex_everything
         connections.each do |conn|
           conn.search(nil) do |object|
             ActiveFedora::Base.find(object.pid, :cast=>true).update_index
           end
         end
-      end 
+      end
 
       private
-      
+
       def connections
         if ActiveFedora.config.sharded?
           return ActiveFedora.config.credentials.map { |cred| ActiveFedora::RubydoraConnection.new(cred).connection}

lib/active_fedora/solr_instance_loader.rb

@@ -0,0 +1,93 @@
+module ActiveFedora
+  class FedoraSolrMismatchError < ActiveFedora::ObjectNotFoundError
+    def initialize(pid, solr_document_id)
+      super("Solr record id and pid do not match; Solr ID=#{solr_document_id}, PID=#{pid}")
+    end
+  end
+
+  # Responsible for loading an ActiveFedora::Base proxy from a Solr document.
+  class SolrInstanceLoader
+    attr_reader :context, :pid
+    private :context, :pid
+    def initialize(context, pid, solr_doc = nil)
+      @context = context
+      @pid = pid
+      @solr_doc = solr_doc
+      validate_solr_doc_and_pid!(@solr_doc)
+    end
+
+    def object
+      return @object if @object
+      @object = allocate_object
+      @object.rels_ext
+      load_object_datastreams(@object)
+      @object.inner_object.freeze
+      @object
+    end
+
+    private
+
+    def allocate_object
+      active_fedora_class.allocate.init_with(solr_digital_object)
+    end
+
+    def solr_digital_object
+      SolrDigitalObject.new(solr_doc, profile_hash, active_fedora_class)
+    end
+
+
+    def load_object_datastreams(obj)
+      obj.datastreams.each_value do |ds|
+        if ds.respond_to?(:profile_from_hash) and (ds_prof = profile_hash['datastreams'][ds.dsid])
+          ds.profile_from_hash(ds_prof)
+        end
+        ds.from_solr(solr_doc) if ds.respond_to?(:from_solr)
+      end
+    end
+
+    def solr_doc
+      @solr_doc ||= begin
+        result = context.find_with_conditions(:id=>pid)
+        if result.empty?
+          raise ActiveFedora::ObjectNotFoundError, "Object #{pid} not found in solr"
+        end
+        @solr_doc = result.first
+        validate_solr_doc_and_pid!(@solr_doc)
+        @solr_doc
+      end
+    end
+
+    def validate_solr_doc_and_pid!(document)
+      return true if document.nil?
+      solr_id = document[SOLR_DOCUMENT_ID]
+      if pid != solr_id
+        raise ActiveFedora::FedoraSolrMismatchError.new(pid, solr_id)
+      end
+    end
+
+    def active_fedora_class
+      @active_fedora_class ||= begin
+        if solr_doc[ActiveFedora::SolrService.solr_name('has_model', :symbol)]
+          ActiveFedora::SolrService.class_from_solr_document(solr_doc)
+        else
+          ActiveFedora::Base
+        end
+      end
+    end
+
+    def profile_json
+      @profile_json ||= begin
+        profile_json = Array(solr_doc[ActiveFedora::Base.profile_solr_name]).first
+        unless profile_json.present?
+          raise ActiveFedora::ObjectNotFoundError, "Object #{pid} does not contain a solrized profile"
+        end
+        profile_json
+      end
+    end
+
+    def profile_hash
+      @profile_hash ||= ActiveSupport::JSON.decode(profile_json)
+    end
+
+  end
+end

spec/integration/solr_instance_loader_spec.rb

@@ -0,0 +1,62 @@
+require 'spec_helper'
+
+require 'active_fedora'
+
+describe ActiveFedora::SolrInstanceLoader do
+  let(:context) { ActiveFedora::Base }
+  let(:pid) { nil }
+  let(:solr_doc) { nil }
+  let(:active_fedora_object) { ActiveFedora::Base.find(pid, :cast => true) }
+  subject { ActiveFedora::SolrInstanceLoader.new(context, pid, solr_doc) }
+
+  describe 'existing pid' do
+    let(:pid) { 'hydrangea:fixture_mods_article1' }
+    describe 'without a solr document' do
+      it 'it finds the SOLR document and casts into an AF::Base object' do
+        expect(subject.object).to eq(active_fedora_object)
+      end
+    end
+    describe 'with matching solr document' do
+      let(:solr_doc) { ActiveFedora::Base.find_with_conditions(:id=>pid).first }
+      it 'it casts the SOLR document and casts into an AF::Base object' do
+        expect(subject.object).to eq(active_fedora_object)
+      end
+    end
+    describe 'with a mismatching solr document' do
+      let(:mismatching_pid) { 'hydrangea:fixture_mods_article2' }
+      let(:solr_doc) { ActiveFedora::Base.find_with_conditions(:id=>mismatching_pid).first }
+      it 'it raise ObjectNotFoundError' do
+        expect {
+          subject
+        }.to raise_error(ActiveFedora::ObjectNotFoundError)
+      end
+    end
+  end
+  describe 'missing pid' do
+    let(:pid) { 'hydrangea:fixture_mods_article8675309' }
+    describe 'without a solr document' do
+      it 'it raise ObjectNotFoundError' do
+        expect {
+          subject.object
+        }.to raise_error(ActiveFedora::ObjectNotFoundError)
+      end
+    end
+    describe 'with matching solr document' do
+      let(:solr_doc) { ActiveFedora::Base.find_with_conditions(:id=>pid).first }
+      it 'it raise ObjectNotFoundError' do
+        expect {
+          subject.object
+        }.to raise_error(ActiveFedora::ObjectNotFoundError)
+      end
+    end
+    describe 'with a mismatching solr document' do
+      let(:mismatching_pid) { 'hydrangea:fixture_mods_article2' }
+      let(:solr_doc) { ActiveFedora::Base.find_with_conditions(:id=>mismatching_pid).first }
+      it 'it raise ObjectNotFoundError' do
+        expect {
+          subject
+        }.to raise_error(ActiveFedora::ObjectNotFoundError)
+      end
+    end
+  end
+end