[Questions] On loading GraphSON encoded graph.

[MartinBrugnara]

Hi all, I am trying to load a GraphSON encoded graph into ArangoDB. The loader fails citing that the labels are not in the collections.

My questions:

• My understanding from #54 is that this implementation requires all vertexes' and edges' labels known in advance. Is this correct?
• Assuming no other labels will be inserted, is there a way to automatically create the needed collections (besides parsing the data and do schema inference myself) ?
• If memory serves me well, this could be hacked in arangodb 2.x but putting all nodes in a collections, let's say V, and all edges in another, E. Eventually, I will need to filter by label like g.traversal().E().hasLabel("knows").count().next"; can I do something similar here?

ArangoDB: 3.0.6 arangodb-tinkerpop-provider: 2.0.2

This is the code I am using to import the graph

String ds = "/data/tinkerpop-modern.json";
ArangoDBConfigurationBuilder builder = new ArangoDBConfigurationBuilder();
Graph g = builder.graph("MAIN_GRAPH");
GraphSONReader.build().create().readGraph(new FileInputStream(new File(ds)), g);
// Tested this too:
// g.io(IoCore.graphson()).readGraph(ds); 

The following is an example of error I get.

Exception in thread "main" java.lang.IllegalArgumentException: Vertex label (person) not in graph (MAIN_GRAPH) vertex collections.

Strangely enough, this is not deterministic: it does not always complain about the same Vertex, sometimes it does it about edges too.

Exception in thread "main" java.lang.IllegalArgumentException: Edge label (knows)not in graph (MAIN_GRAPH) edge collections.

[arcanefoam]

Hi, The Arango Tinkerpop implementation labels are modelled as collections, not as a vertex/edge property. The reasons for this were:

1. The label defines the type of the vertex/edge, so a natural way to store this was using one collection per type.
2. Using labels for types allowed the implementation to rely on Arango's native graph support.

However, a side effect of this is that the implementation looses flexibility as ArangoDB graphs require that the vertex and edge collections are known at graph creation.

A solution would be to use Anonymous Graphs, but that would require the tinkerpop provider to be responsible for graph integrity, a major redesign and code development.

The non-deterministic effect you see might be due to how the GraphSONReader process the information, but its not related to the missing schema information.