Hume Schema Generator

schema-generator,py

from neo4j import GraphDatabase
import json
import random

uri = "bolt://localhost:7687"
driver = GraphDatabase.driver(uri, auth=("neo4j", "neo4j"))
session = driver.session()

q = "CALL db.schema.visualization()"

result = list(session.run(q))
record = result[0]

classes = {}
relationships = {}

types_dict = {'String': 'STRING', 'Long': 'NUMBER', 'Date': 'DATE', 'Point': 'STRING'}

def to_hume_type(t):
  return types_dict[t]

def canvas_position():
  return {'x': random.randint(100, 1200), 'y': random.randint(50, 800)}

for node in record['nodes']:
  classes[node['name']] = {
    'label': node['name'], 
    'primaryKey': False, 
    'searchable': False, 
    'canvasPosition': canvas_position(),
    'icon': 'mdi-circle-outline',
    'color': '#aaa'
    }

for rel in record['relationships']:
  nodeFrom = rel.nodes[0]
  nodeTo = rel.nodes[1]
  relationships[rel.type] = {
    'startId': nodeFrom.id, 
    'startLabel': nodeFrom['name'],
    'endLabel': nodeTo['name'],
    'endId': nodeTo.id, 
    'label': rel.type
    }

q2 = "CALL db.schema.nodeTypeProperties()"
records = list(session.run(q2))

attributes_map = {}

for record in records:
  labels = record['nodeLabels']
  propertyName = record['propertyName']
  propertyTypes = record['propertyTypes']

  if (len(labels) == 1):
    pType = to_hume_type(propertyTypes[0])
    attributes_map.setdefault(labels[0], {'attributes': []})['attributes'].append({'label': propertyName, 'type': pType})

for (key, value) in attributes_map.items():
  classes[key]['attributes'] = list(value['attributes'])

schema = {'classes': list(classes.values()), 'relationships': list(relationships.values())}

with open('schema-generated.json', 'w') as fp:
  json.dump(schema, fp)



    

    

Limitations :

• No support for multi labels
• No support for relationship properties

Note that the available Neo4j procedures do not offer the ability to infer a schema completely when relationship triple patterns are not unique across the schema.

For example :

(:Document)-[:MENTIONS]->(Person)-[:MENTIONS]->(Person)