Neptune with gremlin error when creating edge

Question

I'm new neptune and graph dbs and trying to create a simple edge between two vertexs and getting a weird error that I don't fully understand.

const user = await g.V().has('name', 'john').next()
const group = await g.addV("group").property("name", 'johns created group').next()
 const edge = await g.V(user).addE('memberOf').to(g.V(group)).next(); // this line causes error

The third line causes me to get the following error

Error: The child traversal of ... was not spawned anonymously - use the __ class rather than a TraversalSource to construct the child traversal

Any thoughts on what is going on or how to resolve this issue?

score 1 · Accepted Answer · answered Aug 29 '21 at 20:47

1

After TinkerPop 3.5.0, you can no longer spawn a child traversal from g. It must be spawned anonymously from __ therefore:

g.V(user).addE('memberOf').to(__.V(group))

More information can be found in the Upgrade Documentation for 3.5.0.

answered Aug 29 '21 at 20:47

stephen mallette

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where/how can one access this `__` variable? It appears to not be exported by the `gremlin` package in nodejs. Any ideas? – Uche Ozoemena Apr 13 '22 at 12:52
1

please see Common Imports here: https://tinkerpop.apache.org/docs/current/reference/#gremlin-javascript-imports – stephen mallette Apr 13 '22 at 14:27
You can import `__` with `from gremlin_python.process.graph_traversal import __`. – rbgb Apr 20 '22 at 18:44

Neptune with gremlin error when creating edge

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