Merge pull request #871 from neo4jrb/lazy_association_creation

Lazy association creation

CHANGELOG.md

@@ -10,10 +10,13 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Fixed
 - Added a `before_remove_const` method to clear cached models when Rails `reload!` is called. 5.0.1 included a workaround but this appears to cut to the core of the issue. See https://github.com/neo4jrb/neo4j/pull/855.
+- To prevent errors, changing an index to constraint or constraint to index will drop the existing index/constraint before adding the new.
+- Fixed `AssociationProxy#method_missing` so it properly raises errors.
 
 ### Added
 - Added ability to view `model_class` from `Association` class for `rails_admin` Neo4j adapter
 - QueryProxy `where` will now look for declared properties matching hash keys. When found, it will send the value through that property's type converter if the type matches the property's unconverted state.
+- Improved handling of unpersisted nodes with associations. You can now use `<<` to create associations between unpersisted nodes. A `save` will cascade through unpersisted objects, creating nodes and rels along the way. See https://github.com/neo4jrb/neo4j/pull/871
 
 ## [5.0.4] - 2015-07-17
 

docs/Querying.rst

@@ -76,6 +76,50 @@ Here we are limiting lessons by the ``start_date`` and ``end_date`` on the relat
 
   student.lessons.where(subject: 'Math').rel_where(grade: 85)
 
+
+Associations and Unpersisted Nodes
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+There is some special behavior around association creation when nodes are new and unsaved. Below are a few scenarios and their outcomes.
+
+When both nodes are persisted, associations changes using ``<<`` or ``=`` take place immediately -- no need to call save.
+
+.. code-block:: ruby
+
+  student = Student.first
+  Lesson = Lesson.first
+  student.lessons << lesson
+
+In that case, the relationship would be created immediately.
+
+When the node on which the association is called is unpersisted, no changes are made to the database until ``save`` is called. Once that happens, a cascading save event will occur.
+
+.. code-block:: ruby
+
+  student = Student.new
+  lesson = Lesson.first || Lesson.new
+  # This method will not save `student` or change relationships in the database:
+  student.lessons << lesson
+
+Once we call ``save`` on ``student``, two or three things will happen:
+
+* Since ``student`` is unpersisted, it will be saved
+* If ``lesson`` is unpersisted, it will be saved
+* Once both nodes are saved, the relationship will be created
+
+This process occurs within a transaction. If any part fails, an error will be raised, the transaction will fail, and no changes will be made to the database.
+
+Finally, if you try to associate an unpersisted node with a persisted node, the unpersisted node will be saved and the relationship will be created immediately:
+
+.. code-block:: ruby
+
+  student = Student.first
+  lesson = Lesson.new
+  student.lessons << lesson
+
+In the above example, ``lesson`` would be saved and the relationship would be created immediately. There is no need to call ``save`` on ``student``.
+
+
 Parameters
 ~~~~~~~~~~
 

docs/api/Neo4j.rst

@@ -13,18 +13,18 @@ Neo4j
 
    Neo4j/Config
 
-   Neo4j/Shared
-
    Neo4j/Neo4jrbError
 
    Neo4j/RecordNotFound
 
+   Neo4j/Shared
+
+   Neo4j/Railtie
+
 
 
    Neo4j/ClassWrapper
 
-   Neo4j/Railtie
-
    Neo4j/Paginated
 
    Neo4j/Migration
@@ -62,16 +62,16 @@ Files
 
   * `lib/neo4j/config.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/config.rb#L1>`_
 
+  * `lib/neo4j/errors.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/errors.rb#L1>`_
+
   * `lib/neo4j/shared.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/shared.rb#L1>`_
 
-  * `lib/neo4j/errors.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/errors.rb#L1>`_
+  * `lib/neo4j/railtie.rb:4 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/railtie.rb#L4>`_
 
   * `lib/neo4j/version.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/version.rb#L1>`_
 
   * `lib/neo4j/wrapper.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/wrapper.rb#L1>`_
 
-  * `lib/neo4j/railtie.rb:4 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/railtie.rb#L4>`_
-
   * `lib/neo4j/paginated.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/paginated.rb#L1>`_
 
   * `lib/neo4j/migration.rb:3 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/migration.rb#L3>`_
@@ -82,18 +82,18 @@ Files
 
   * `lib/neo4j/type_converters.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/type_converters.rb#L1>`_
 
-  * `lib/neo4j/active_rel/types.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_rel/types.rb#L1>`_
-
   * `lib/neo4j/shared/callbacks.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/shared/callbacks.rb#L1>`_
 
+  * `lib/neo4j/active_rel/types.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_rel/types.rb#L1>`_
+
   * `lib/neo4j/active_node/query.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query.rb#L1>`_
 
   * `lib/neo4j/shared/typecaster.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/shared/typecaster.rb#L1>`_
 
-  * `lib/neo4j/active_node/labels.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/labels.rb#L1>`_
-
   * `lib/neo4j/shared/validations.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/shared/validations.rb#L1>`_
 
+  * `lib/neo4j/active_node/labels.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/labels.rb#L1>`_
+
   * `lib/neo4j/active_rel/callbacks.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_rel/callbacks.rb#L1>`_
 
   * `lib/neo4j/active_node/callbacks.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/callbacks.rb#L1>`_
@@ -102,10 +102,12 @@ Files
 
   * `lib/neo4j/active_rel/validations.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_rel/validations.rb#L1>`_
 
-  * `lib/neo4j/active_node/orm_adapter.rb:3 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/orm_adapter.rb#L3>`_
-
   * `lib/neo4j/active_node/validations.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/validations.rb#L1>`_
 
+  * `lib/neo4j/active_node/unpersisted.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/unpersisted.rb#L1>`_
+
+  * `lib/neo4j/active_node/orm_adapter.rb:3 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/orm_adapter.rb#L3>`_
+
   * `lib/neo4j/active_node/query_methods.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query_methods.rb#L1>`_
 
   * `lib/rails/generators/neo4j_generator.rb:5 <https://github.com/neo4jrb/neo4j/blob/master/lib/rails/generators/neo4j_generator.rb#L5>`_
@@ -122,6 +124,8 @@ Files
 
   * `lib/neo4j/active_node/dependent/query_proxy_methods.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/dependent/query_proxy_methods.rb#L1>`_
 
+  * `lib/neo4j/active_node/query/query_proxy_unpersisted.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query/query_proxy_unpersisted.rb#L1>`_
+
   * `lib/neo4j/active_node/dependent/association_methods.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/dependent/association_methods.rb#L1>`_
 
   * `lib/neo4j/active_node/query/query_proxy_eager_loading.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query/query_proxy_eager_loading.rb#L1>`_

docs/api/Neo4j/ActiveNode.rst

@@ -27,10 +27,10 @@ in a new object of that class.
 
    ActiveNode/Rels
 
-   ActiveNode/Scope
-
    ActiveNode/Query
 
+   ActiveNode/Scope
+
    ActiveNode/HasN
 
    ActiveNode/Labels
@@ -41,20 +41,22 @@ in a new object of that class.
 
    ActiveNode/Dependent
 
-   ActiveNode/Reflection
-
    ActiveNode/Initialize
 
-   ActiveNode/IdProperty
-
-   ActiveNode/ClassMethods
+   ActiveNode/Reflection
 
-   ActiveNode/OrmAdapter
+   ActiveNode/IdProperty
 
    ActiveNode/Validations
 
    ActiveNode/Persistence
 
+   ActiveNode/Unpersisted
+
+   ActiveNode/ClassMethods
+
+   ActiveNode/OrmAdapter
+
    ActiveNode/QueryMethods
 
 
@@ -82,10 +84,10 @@ Files
 
   * `lib/neo4j/active_node/rels.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/rels.rb#L1>`_
 
-  * `lib/neo4j/active_node/scope.rb:3 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/scope.rb#L3>`_
-
   * `lib/neo4j/active_node/query.rb:2 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query.rb#L2>`_
 
+  * `lib/neo4j/active_node/scope.rb:3 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/scope.rb#L3>`_
+
   * `lib/neo4j/active_node/has_n.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/has_n.rb#L1>`_
 
   * `lib/neo4j/active_node/labels.rb:2 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/labels.rb#L2>`_
@@ -100,12 +102,14 @@ Files
 
   * `lib/neo4j/active_node/id_property.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/id_property.rb#L1>`_
 
-  * `lib/neo4j/active_node/orm_adapter.rb:4 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/orm_adapter.rb#L4>`_
-
   * `lib/neo4j/active_node/validations.rb:2 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/validations.rb#L2>`_
 
   * `lib/neo4j/active_node/persistence.rb:1 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/persistence.rb#L1>`_
 
+  * `lib/neo4j/active_node/unpersisted.rb:2 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/unpersisted.rb#L2>`_
+
+  * `lib/neo4j/active_node/orm_adapter.rb:4 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/orm_adapter.rb#L4>`_
+
   * `lib/neo4j/active_node/query_methods.rb:2 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query_methods.rb#L2>`_
 
   * `lib/neo4j/active_node/has_n/association.rb:4 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/has_n/association.rb#L4>`_
@@ -120,6 +124,8 @@ Files
 
   * `lib/neo4j/active_node/dependent/query_proxy_methods.rb:2 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/dependent/query_proxy_methods.rb#L2>`_
 
+  * `lib/neo4j/active_node/query/query_proxy_unpersisted.rb:2 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query/query_proxy_unpersisted.rb#L2>`_
+
   * `lib/neo4j/active_node/dependent/association_methods.rb:2 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/dependent/association_methods.rb#L2>`_
 
   * `lib/neo4j/active_node/query/query_proxy_eager_loading.rb:2 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query/query_proxy_eager_loading.rb#L2>`_
@@ -671,6 +677,32 @@ Methods
 
 
 
+.. _`Neo4j/ActiveNode#pending_associations`:
+
+**#pending_associations**
+
+
+  .. hidden-code-block:: ruby
+
+     def pending_associations
+       @pending_associations ||= {}
+     end
+
+
+
+.. _`Neo4j/ActiveNode#pending_associations?`:
+
+**#pending_associations?**
+
+
+  .. hidden-code-block:: ruby
+
+     def pending_associations?
+       !@pending_associations.blank?
+     end
+
+
+
 .. _`Neo4j/ActiveNode#persisted?`:
 
 **#persisted?**

docs/api/Neo4j/ActiveNode/HasN.rst

@@ -27,10 +27,6 @@ HasN
 
 
 
-
-
-
-
    HasN/ClassMethods
 
    HasN/Association

docs/api/Neo4j/ActiveNode/HasN/AssociationProxy.rst

@@ -184,13 +184,11 @@ Methods
 
      def method_missing(method_name, *args, &block)
        target = target_for_missing_method(method_name)
+       super if target.nil?
      
        cache_query_proxy_result if !cached? && !target.is_a?(Neo4j::ActiveNode::Query::QueryProxy)
-
        clear_cache_result if target.is_a?(Neo4j::ActiveNode::Query::QueryProxy)
 
-       return if target.nil?
-
        target.public_send(method_name, *args, &block)
      end
 

docs/api/Neo4j/ActiveNode/HasN/ClassMethods.rst

@@ -64,7 +64,7 @@ Files
 
 
 
-  * `lib/neo4j/active_node/has_n.rb:170 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/has_n.rb#L170>`_
+  * `lib/neo4j/active_node/has_n.rb:158 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/has_n.rb#L158>`_
 
 
 

docs/api/Neo4j/ActiveNode/Persistence.rst

@@ -21,6 +21,8 @@ Persistence
 
 
 
+
+
    Persistence/ClassMethods
 
 
@@ -119,7 +121,7 @@ Methods
        node = _create_node(properties)
        init_on_load(node, node.props)
        send_props(@relationship_props) if @relationship_props
-       @relationship_props = nil
+       @relationship_props = @deferred_nodes = nil
        true
      end
 
@@ -326,8 +328,10 @@ Methods
 
      def save(*)
        update_magic_properties
-       association_proxy_cache.clear
-       create_or_update
+       cascade_save do
+         association_proxy_cache.clear
+         create_or_update
+       end
      end
 
 

docs/api/Neo4j/ActiveNode/Persistence/ClassMethods.rst

@@ -48,7 +48,7 @@ Files
 
 
 
-  * `lib/neo4j/active_node/persistence.rb:69 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/persistence.rb#L69>`_
+  * `lib/neo4j/active_node/persistence.rb:85 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/persistence.rb#L85>`_
 
 
 
@@ -68,7 +68,6 @@ Methods
 
      def create(props = {})
        association_props = extract_association_attributes!(props) || {}
-
        new(props).tap do |obj|
          yield obj if block_given?
          obj.save

docs/api/Neo4j/ActiveNode/Query.rst

@@ -25,6 +25,8 @@ Helper methods to return Neo4j::Core::Query objects.  A query object can be used
 
    Query/QueryProxyEnumerable
 
+   Query/QueryProxyUnpersisted
+
    Query/QueryProxyEagerLoading
 
    Query/QueryProxyFindInBatches
@@ -54,6 +56,8 @@ Files
 
   * `lib/neo4j/active_node/query/query_proxy_enumerable.rb:3 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query/query_proxy_enumerable.rb#L3>`_
 
+  * `lib/neo4j/active_node/query/query_proxy_unpersisted.rb:3 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query/query_proxy_unpersisted.rb#L3>`_
+
   * `lib/neo4j/active_node/query/query_proxy_eager_loading.rb:3 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query/query_proxy_eager_loading.rb#L3>`_
 
   * `lib/neo4j/active_node/query/query_proxy_find_in_batches.rb:3 <https://github.com/neo4jrb/neo4j/blob/master/lib/neo4j/active_node/query/query_proxy_find_in_batches.rb#L3>`_