Relationship API bug fixes & updates

[michaeldgraham]

This PR includes various bug fixes that open up API features for interfaced @relation type fields, as well as some fixes to long-standing bugs with relationship field orderBy arguments.

Interfaced relationship types

#142 - Relationship with properties doesn't build with interface types.
The schema augmentation process now handles @relation types that use an interface type for either or both of it's incoming and outgoing node types.

• query interfaced relationship type field for outgoing object type nodes
• query interfaced relationship type field for incoming interface type nodes
• query incoming interface type nodes using fragments in relationship type field
• query reflexive interfaced relationship type field using fragments
• query reflexive interface type relationship field
• query reflexive interface type relationship field using fragments

#201 - Cannot generate multi-type relationships
The custom error shown at the bottom of this issue has been removed and the Add, Remove, Update, and Merge relationship type mutations are now generated and translated, shown with these tests:

• Add interfaced relationship type mutation
• Remove interfaced relationship type mutation
• Merge interfaced relationship type mutation
• Update interfaced relationship type mutation

Filtering

#477 - [Regression] 2.14.4 Breaks Nested Filters Previously Working in 2.14.0
Beginning with issue #446 and proceeding into #409, this issue arose due to a misinterpretation of the direction to use when querying the incoming nodes of a relationship type from the outgoing type node. The initial fix in #469 was incorrect and has been revised and covered by the following tests:

• Nested filter for relationship type outgoing nodes
• Nested filter for relationship type incoming nodes
• Root and nested relationship type filter

#409 - Nested Filters do not work as expected for Interface types

• fliter interfaced relationship type field for outgoing object type nodes
• fliter interfaced relationship type field for incoming interface type nodes
• filter incoming interface type nodes using only fragments in relationship type field
• filter reflexive interfaced relationship type field

Ordering

#173 - [BUG] Nested ordering errors
#272 - [Suggestion] Ordering by temporal field in relations
#373 - DateTime Ordering Argument Not Impacting Order
For quite some time, there has been a bug in nested ordering that causes it to silently fail when not also selecting the same fields being ordered. This issue was a result of misinterpreting how to handle the limitation of using apoc.coll.sortMulti and has been resolved in this PR. The translation strategy developed based on the misunderstanding was relied on in some post-processing code used for temporal ordering, so it showed up explicitly as a translation error in those cases.

• Deeply nested query using temporal orderBy (updated)
• query for relationship properties using orderBy argument
• query nested relationship with differences between selected and ordered fields
• Deeply nested query using temporal orderBy without temporal field selection

#232 - Add first, offset, orderBy generated arguments for relationship type fields
The first, offset, and orderBy query arguments are now added to @relation type fields and translated according to the below tests:

• query interfaced relationship type using inline fragment and pagination
• query interfaced relation using inline fragment and pagination
• order interfaced relationship type field for incoming interface type nodes
• order interfaced relationship type field for outgoing object type nodes
• order incoming interface type nodes using fragments in relationship type field
• order incoming and outgoing nodes of reflexive interfaced relationship type field

Relevant remaining issues

#218 - Relationship mutation wrong return when only "to" fields are requested

[Phylodome]

Any idea as to when this PR's (much anticipated) changes will be published as an updated package version?

[johnymontana]

@Phylodome it's now been published in v2.15.0

[Phylodome]

Wonderful. Thanks for the update!