aim: transform Neo4j Record to G6 , stuck at how to skip duplicate nodes

[scarletfrank]

Aim

• transform Neo4j Records to G6 format
• can not figure out how neovis.js avoid adding duplicate nodes

Problem

Example Cypher: MATCH (b)-[re]-(c) RETURN b, re, c LIMIT 10

As the case of neovis

  viz.render();
  console.log(viz._edges);
  console.log(viz._nodes);
// ----
{id: 59085, from: 11496, to: 15468, raw: Relationship, title: "", …}
{id: 59087, from: 18665, to: 15468, raw: Relationship, title: "", ...}
// ----
{id: 15468, raw: Node, value: 1, label: "  ", group: 2, …}
{id: 11496, raw: Node, value: 1, label: "  ", group: 2, …}
{id: 18665, raw: Node, value: 1, label: "  ", group: 2, …}

I use use-neo4j as a React wrapper to access Neo4j. It returns Neo4jRecord which is actually Record from Neo4j-Driver .

[Record, Record, Record, Record, Record, Record, Record, Record, Record, Record]
Record.toObject()  // = > {n: Node, re: Relationship, b: Node}

Inevitably, I have to skip the duplicate nodes. I know neovis works well. I find a similar implementation at this developer blog, in which it says

Next, we have to convert the returned results from Neo4j which is a list of records into a format that is D3 compatible. 
neovis.js provides a very good guide on how to achieve this and for the most part, we copied their code.

[thebestnom]

I don't think we actually skip duplicates, if I remember correctly we add everything to vis DataSet by id, so it should just override the last one in case of duplicates (same as using hashmap)

(Neo4j node and relationship comes with unique id)

[scarletfrank]

Thanks for quick reply.

OMG. I think I find the key to the problem, but I am still a little bit confused.

_addNode(node) {
this._nodes[node.id] = node;
}

Yes, It will override the node with the same id.

As for the developer blog, I am not sure whether Motif inherit the neo4j-driver logic

let nodes: Node[] = []; // Node from `neo4j-driver`
let startNode = buildNode(v.start);
nodes.push(startNode); 

Maybe the last line is equivalent to Node[startNode.identity] = startNode;

[scarletfrank]

I would complete my neo4j-g6-demo this week.
After that, I will leave the link and close this issue.

[thebestnom]

Thanks for quick reply.

OMG. I think I find the key to the problem, but I am still a little bit confused.

_addNode(node) {
this._nodes[node.id] = node;
}

Yes, It will override the node with the same id.

As for the developer blog, I am not sure whether Motif inherit the neo4j-driver logic

let nodes: Node[] = []; // Node from `neo4j-driver`
let startNode = buildNode(v.start);
nodes.push(startNode); 

Maybe the last line is equivalent to Node[startNode.identity] = startNode;

Nope 😅 it looks like they have the same problem as you (also the code is a little bit different on 2.0.0 but it does the same thing)

[thebestnom]

I think that if they use a network library most of them know as well to merge same id

[thebestnom]

But in their data it most likely have duplicates

[scarletfrank]

I successfully implement it. The code is here

I also combine it with Graphin in the my react-graphapp.

Although it works fine with my local Neo4j Docker instances , it still needs to be developed for richer customization.

I think the issue is solved. Thanks.