Add basic MongoDB test

Author: ellnix

lib/meilisearch-rails.rb

@@ -476,7 +476,8 @@ def meilisearch(options = {}, &block)
                 super(*args)
               end
             end
-          elsif respond_to?(:after_destroy)
+          # Currently after_destroy_commit is broken in Mongoid
+          elsif respond_to?(:after_destroy) && !Utilities.mongo_model?(self)
             after_destroy_commit { |searchable| searchable.ms_enqueue_remove_from_index!(ms_synchronous?) }
           end
         end
@@ -690,6 +691,8 @@ def ms_search(query, params = {})
         # respond with a valid database column. The blocks below prevent that from happening.
         has_virtual_column_as_pk = if defined?(::Sequel::Model) && self < Sequel::Model
                                      meilisearch_options[:type].columns.map(&:to_s).exclude?(condition_key.to_s)
+                                   elsif Utilities.mongo_model?(self)
+                                     fields.keys.exclude?(condition_key.to_s)
                                    else
                                      meilisearch_options[:type].columns.map(&:name).map(&:to_s).exclude?(condition_key.to_s)
                                    end
@@ -778,7 +781,7 @@ def ms_must_reindex?(document)
 
       def ms_primary_key_method(options = nil)
         options ||= meilisearch_options
-        options[:primary_key] || options[:id] || :id
+        options[:primary_key] || options[:id] || (Utilities.mongo_model?(self) ? :_id : :id)
       end
 
       protected

spec/integration/mongoid/record_is_created_spec.rb

@@ -0,0 +1,11 @@
+require 'support/mongo_models/citizen'
+
+describe 'MongoDB record is created' do
+  it 'is added to meilisearch' do
+    john_wick = Citizen.create(name: 'John Wick', age: 40)
+
+    AsyncHelper.await_last_task
+
+    expect(Citizen.search('John')).to eq([john_wick])
+  end
+end

spec/support/mongo_models/citizen.rb

@@ -0,0 +1,11 @@
+class Citizen
+  include Mongoid::Document
+  include Mongoid::Timestamps
+
+  field :name, type: String
+  field :age, type: Integer
+
+  include MeiliSearch::Rails
+
+  meilisearch index_uid: safe_index_uid('Citizen')
+end