[Python] Turning on `IF NOT EXISTS` while creating schemas and relationships in neo4j /...

Recently I switched from using Cypher queries to neomodel OGM. Although it simplified codebase, there's still an issue I can't solve. While using Cypher, I could simply write CREATE <object> IF NOT EXISTS, and execution plan would be understandable enough: if exists - do nothing, if doesn't - create. After switching to neomodel, I've created following:

• Service responsible for calling Neo4J using Neomodel:

from models.neo4j_models import (
...
)
from neomodel import config, db
...


class GraphDBService:
def __init__(self, uri: str, username: str, password: str):
...
self._initialize_db() # IMPORTANT: called every time when service is created
...

def _initialize_db(self) -> None:
"""Initialize database with constraints and indexes"""

try:
db.install_all_labels()
logger.info("Neo4j constraints and indexes installed via neomodel")
except Exception as e:
logger.error(f"Error initializing Neo4j schema: {str(e)}", exc_info=True)
raise GraphDBError(f"Failed to initialize Neo4j schema: {str(e)}")

• Model to be created (models.neo4j_models):

from neomodel import (
StringProperty, ...
)

class Company(StructuredNode):
"""
Company node representing an organization where a person has worked
"""
name = StringProperty(unique_index=True, required=True)
...


It works as expected (according to their doc), but what I do not like is following:

• Use service 1st time
  • All models, relationships and so on are created (as expected)
• Disconnect from service and reconnect again
  • All models and so on are created again (as expected)

During second round, my trace is heavily cluttered by logs of following type:

cv-storage-service-1 | Found models.neo4j_models.Company
cv-storage-service-1 | + Creating node unique constraint for name on label Company for class models.neo4j_models.Company
cv-storage-service-1 | {code: Neo.ClientError.Schema.EquivalentSchemaRuleAlreadyExists} {message: An equivalent constraint already exists, 'Constraint( id=17, name='constraint_unique_Company_name', type='NODE PROPERTY UNIQUENESS', schema=Company {name}), ownedIndex=16 )'.}


Although I could find a solution checking whether calling _initialize_db() is justified or not, I would prefer simpler solution: just to pass a construct/flag/whatever that will tell neo sort of IF <this> NOT EXISTS, create. How could I do that?

If passing extra param is not an option, how could I change logs dropping straight from Neo4J? Core issue here is that all these "Errors" contain word Error, thus awfully increasing number of errors in log, and instead of having 100x+ Sorry, can't create, it already exists INFO-messages I get 100x+ "errors" that need not to be solved (from my point of view).

Workaround in this GitHub issue works as of now, but to be honest, I'd prefer to get a solution rather than a workaround


Tech: MacOS Sonoma 14.6.1, Python 3.11, neomodel 5.4.4

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