Gh-3253 Fix custom types in gremlin

[tb06904]

Fixes the usage of custom Gaffer types not being able to be handled by a Gremlin client.

Works by simply making sure whenever conversion from Gaffer element to Tinkerpop element any custom types are converted to string representation and vice versa so that results can be parsed fine by a Gremlin client or Gaffer. This does mean slight overhead as conversions will happen even if Gremlin does not return the step result to the client but there is no way round this as each Gremlin step in theory can be returned so always needs any custom types converted.

Main type that is always converted is the Gaffer TypeSubTypeValue but more could be added, the string format has also been changed to be the same as the .toString so can more easily pass back in results, but a slight short hand is also accepted in Gremlin queries like [type=thetype,subType=thesubtype,value=thevalue]

Related issue

• Resolve TSTV can't deserialise when using a Gremlin connection #3253

[codecov]

Codecov Report

Attention: Patch coverage is 90.24390% with 8 lines in your changes missing coverage. Please review.

Project coverage is 67.27%. Comparing base (0d7f7a7) to head (60a5705).

Files	Patch %	Lines
...rocess/traversal/util/GafferCustomTypeFactory.java	87.09%	2 Missing and 2 partials ⚠️
...a/uk/gov/gchq/gaffer/tinkerpop/GafferPopGraph.java	90.90%	1 Missing ⚠️
...affer/tinkerpop/generator/GafferEdgeGenerator.java	87.50%	0 Missing and 1 partial ⚠️
...er/tinkerpop/generator/GafferPopEdgeGenerator.java	87.50%	0 Missing and 1 partial ⚠️
.../tinkerpop/generator/GafferPopVertexGenerator.java	85.71%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             develop    #3255      +/-   ##
=============================================
- Coverage      67.28%   67.27%   -0.01%     
+ Complexity      2572     2569       -3     
=============================================
  Files            926      926              
  Lines          29738    29771      +33     
  Branches        3290     3289       -1     
=============================================
+ Hits           20009    20029      +20     
- Misses          8282     8289       +7     
- Partials        1447     1453       +6     

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[p29876]

All looks fine, just need to remember to update the docs with the new TSTV String format.

Am I right in thinking this means you can no longer get a TSTV object from a GafferPop graph, you'll only ever get the String in case you're querying from the server?
If so, assuming actual TSTV objects is something users would want, should we add a helper method to create a TSTV from the String representation to save them from parsing it themselves on the other end? e.g. a new constructor or a static TypeSubTypeValue.from(tstvString)

[p29876]

All looks fine, just need to remember to update the docs with the new TSTV String format.

Am I right in thinking this means you can no longer get a TSTV object from a GafferPop graph, you'll only ever get the String in case you're querying from the server? If so, assuming actual TSTV objects is something users would want, should we add a helper method to create a TSTV from the String representation to save them from parsing it themselves on the other end? e.g. a new constructor or a static TypeSubTypeValue.from(tstvString)

Ignore me, you can do that with the new custom types factory
I was thinking we could have something more concrete that would return a TSTV or throw if invalid or something but it would just be a duplication of this method and it's probably fine as is

[tb06904]

All looks fine, just need to remember to update the docs with the new TSTV String format.

Am I right in thinking this means you can no longer get a TSTV object from a GafferPop graph, you'll only ever get the String in case you're querying from the server? If so, assuming actual TSTV objects is something users would want, should we add a helper method to create a TSTV from the String representation to save them from parsing it themselves on the other end? e.g. a new constructor or a static TypeSubTypeValue.from(tstvString)

You are right basically, if the results are returned as Tinkerpop a Vertex or Edge it will have any custom types made safe as strings, you can always pass these back through a Gaffer element generator to make them into a Gaffer Entity or Edge though which will convert the types back or use the static util method.

[sonarcloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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