SSLEOFError with python 3.14

[nikhiltyagi1991]

Code Sample, a copy-pastable example if possible

from azure.kusto.data import KustoClient, KustoConnectionStringBuilder
kcsb = KustoConnectionStringBuilder.with_aad_device_authentication(
    'https://nik-adx.centralus.kusto.windows.net', '<tenant-id>'
)
client = KustoClient(kcsb)
query = "raw_ingestion | limit 1"
response = client.execute('test-db', query)

Problem description

I keep getting SSLEOFError while connecting to ADX:

If query related, does it happen on other platforms (Kusto Web UI, Kusto Explorer)?

It works as expected in Kusto Web UI. Only getting error with python library, works well in NodeJS.
I created new Azure Data Explorer cluster with test-db, generic test data.

.create table raw_ingestion (
    truck_id: string,
    truck_type: string,
    tire_temp: real,
    event_timestamp: datetime,
    ingestion_timestamp: datetime
)


.ingest inline into table raw_ingestion <|
truck_id,truck_type,tire_temp,event_timestamp,ingestion_timestamp
T100,HaulTruck,78.5,2026-03-14T08:00:00Z,2026-03-14T08:00:05Z
T101,HaulTruck,81.2,2026-03-14T08:01:00Z,2026-03-14T08:01:04Z
T102,Loader,74.9,2026-03-14T08:02:00Z,2026-03-14T08:02:06Z
T100,HaulTruck,79.1,2026-03-14T08:03:00Z,2026-03-14T08:03:05Z
T103,Drill,69.4,2026-03-14T08:04:00Z,2026-03-14T08:04:03Z
T101,HaulTruck,82.0,2026-03-14T08:05:00Z,2026-03-14T08:05:07Z
T104,Dozer,71.6,2026-03-14T08:06:00Z,2026-03-14T08:06:02Z
T102,Loader,75.3,2026-03-14T08:07:00Z,2026-03-14T08:07:04Z
T100,HaulTruck,80.4,2026-03-14T08:08:00Z,2026-03-14T08:08:05Z
T105,Excavator,77.8,2026-03-14T08:09:00Z,2026-03-14T08:09:06Z

Seeing this error frequently. This happens for python >3.9. Works fine with python==3.9.

Output of pip freeze

Details

[paste the output of pip freeze here below this line]
anyio==4.12.1
appnope==0.1.4
argon2-cffi==25.1.0
argon2-cffi-bindings==25.1.0
arrow==1.4.0
asttokens==3.0.1
async-lru==2.2.0
attrs==25.4.0
azure-core==1.38.3
azure-identity==1.25.3
azure-kusto-data==6.0.2
babel==2.18.0
beautifulsoup4==4.14.3
bleach==6.3.0
certifi==2026.2.25
cffi==2.0.0
charset-normalizer==3.4.5
comm==0.2.3
cryptography==46.0.5
debugpy==1.8.20
decorator==5.2.1
defusedxml==0.7.1
executing==2.2.1
fastjsonschema==2.21.2
fqdn==1.5.1
h11==0.16.0
httpcore==1.0.9
httpx==0.28.1
idna==3.11
ijson==3.4.0.post0
ipykernel==7.2.0
ipython==9.11.0
ipython-pygments-lexers==1.1.1
ipywidgets==8.1.8
isoduration==20.11.0
jedi==0.19.2
jinja2==3.1.6
json5==0.13.0
jsonpointer==3.0.0
jsonschema==4.26.0
jsonschema-specifications==2025.9.1
jupyter==1.1.1
jupyter-client==8.8.0
jupyter-console==6.6.3
jupyter-core==5.9.1
jupyter-events==0.12.0
jupyter-lsp==2.3.0
jupyter-server==2.17.0
jupyter-server-terminals==0.5.4
jupyterlab==4.5.6
jupyterlab-pygments==0.3.0
jupyterlab-server==2.28.0
jupyterlab-widgets==3.0.16
lark==1.3.1
markupsafe==3.0.3
matplotlib-inline==0.2.1
mistune==3.2.0
msal==1.35.1
msal-extensions==1.3.1
nbclient==0.10.4
nbconvert==7.17.0
nbformat==5.10.4
nest-asyncio==1.6.0
notebook==7.5.5
notebook-shim==0.2.4
packaging==26.0
pandocfilters==1.5.1
parso==0.8.6
pexpect==4.9.0
platformdirs==4.9.4
prometheus-client==0.24.1
prompt-toolkit==3.0.52
psutil==7.2.2
ptyprocess==0.7.0
pure-eval==0.2.3
pycparser==3.0
pygments==2.19.2
pyjwt==2.12.1
python-dateutil==2.9.0.post0
python-json-logger==4.0.0
pyyaml==6.0.3
pyzmq==27.1.0
referencing==0.37.0
requests==2.32.5
rfc3339-validator==0.1.4
rfc3986-validator==0.1.1
rfc3987-syntax==1.1.0
rpds-py==0.30.0
send2trash==2.1.0
setuptools==82.0.1
six==1.17.0
soupsieve==2.8.3
stack-data==0.6.3
terminado==0.18.1
tinycss2==1.4.0
tornado==6.5.5
traitlets==5.14.3
typing-extensions==4.15.0
tzdata==2025.3
uri-template==1.3.0
urllib3==2.6.3
wcwidth==0.6.0
webcolors==25.10.0
webencodings==0.5.1
websocket-client==1.9.0
widgetsnbextension==4.0.15

[ag-ramachandran]

Nikhil, acked. Having a look

[ag-ramachandran]

Hello @nikhiltyagi1991

Spun up a small main program to test the same program. It seemed to work without a hitch. No additional library was installed, just tried it with the data and ingest packages

> python --version
Python 3.14.0
> python3 main.py https://x.southeastasia.kusto.windows.net e2e
Cluster: https://x.southeastasia..kusto.windows.net
Database: e2e

Creating table 'raw_ingestion'...
Table created (or already exists).
Ingesting sample data into 'raw_ingestion'...
Data ingested.

Querying: raw_ingestion | limit 10

truck_id | truck_type | tire_temp | event_timestamp | ingestion_timestamp
-----------------------------------------------------------------------------------------------------------------------------
T100 | HaulTruck | 78.5 | 2026-03-14 08:00:00+00:00 | 2026-03-14 08:00:05+00:00
T101 | HaulTruck | 81.2 | 2026-03-14 08:01:00+00:00 | 2026-03-14 08:01:04+00:00
T102 | Loader | 74.9 | 2026-03-14 08:02:00+00:00 | 2026-03-14 08:02:06+00:00
T100 | HaulTruck | 79.1 | 2026-03-14 08:03:00+00:00 | 2026-03-14 08:03:05+00:00
T103 | Drill | 69.4 | 2026-03-14 08:04:00+00:00 | 2026-03-14 08:04:03+00:00
T101 | HaulTruck | 82.0 | 2026-03-14 08:05:00+00:00 | 2026-03-14 08:05:07+00:00
T104 | Dozer | 71.6 | 2026-03-14 08:06:00+00:00 | 2026-03-14 08:06:02+00:00
T102 | Loader | 75.3 | 2026-03-14 08:07:00+00:00 | 2026-03-14 08:07:04+00:00
T100 | HaulTruck | 80.4 | 2026-03-14 08:08:00+00:00 | 2026-03-14 08:08:05+00:00
T105 | Excavator | 77.8 | 2026-03-14 08:09:00+00:00 | 2026-03-14 08:09:06+00:00

Total rows returned: 10

Done.

The sample app was

"""
Quick-start script for issue #626 reproduction.
Creates a raw_ingestion table, ingests sample data, and queries it.

Usage:
    python main.py <cluster_url> <database>

Example:
    python main.py https://mycluster.centralus.kusto.windows.net mydb
"""
import argparse
import sys
import time

from azure.identity import DefaultAzureCredential
from azure.kusto.data import KustoClient, KustoConnectionStringBuilder


TABLE_NAME = "raw_ingestion"

CREATE_TABLE_CMD = f""".create-merge table {TABLE_NAME} (
    truck_id: string,
    truck_type: string,
    tire_temp: real,
    event_timestamp: datetime,
    ingestion_timestamp: datetime
)"""

INGEST_CMD = f""".ingest inline into table {TABLE_NAME} <|
T100,HaulTruck,78.5,2026-03-14T08:00:00Z,2026-03-14T08:00:05Z
T101,HaulTruck,81.2,2026-03-14T08:01:00Z,2026-03-14T08:01:04Z
T102,Loader,74.9,2026-03-14T08:02:00Z,2026-03-14T08:02:06Z
T100,HaulTruck,79.1,2026-03-14T08:03:00Z,2026-03-14T08:03:05Z
T103,Drill,69.4,2026-03-14T08:04:00Z,2026-03-14T08:04:03Z
T101,HaulTruck,82.0,2026-03-14T08:05:00Z,2026-03-14T08:05:07Z
T104,Dozer,71.6,2026-03-14T08:06:00Z,2026-03-14T08:06:02Z
T102,Loader,75.3,2026-03-14T08:07:00Z,2026-03-14T08:07:04Z
T100,HaulTruck,80.4,2026-03-14T08:08:00Z,2026-03-14T08:08:05Z
T105,Excavator,77.8,2026-03-14T08:09:00Z,2026-03-14T08:09:06Z"""

QUERY = f"{TABLE_NAME} | limit 10"


def create_client(cluster_url: str) -> KustoClient:
    credential = DefaultAzureCredential()
    kcsb = KustoConnectionStringBuilder.with_azure_token_credential(cluster_url, credential)
    return KustoClient(kcsb)


def create_table(client: KustoClient, database: str) -> None:
    print(f"Creating table '{TABLE_NAME}'...")
    client.execute_mgmt(database, CREATE_TABLE_CMD)
    print("Table created (or already exists).")


def ingest_data(client: KustoClient, database: str) -> None:
    print(f"Ingesting sample data into '{TABLE_NAME}'...")
    client.execute_mgmt(database, INGEST_CMD)
    print("Data ingested.")


def query_data(client: KustoClient, database: str) -> None:
    print(f"\nQuerying: {QUERY}")
    response = client.execute(database, QUERY)

    for table in response.primary_results:
        columns = [col.column_name for col in table.columns]
        print(f"\n{' | '.join(columns)}")
        print("-" * (len(columns) * 25))
        for row in table:
            print(" | ".join(str(row[col]) for col in columns))
    print(f"\nTotal rows returned: {len(response.primary_results[0])}")


def main() -> None:
    parser = argparse.ArgumentParser(description="Quick-start: create table, ingest, and query ADX.")
    parser.add_argument("cluster_url", help="ADX cluster URL (e.g. https://mycluster.centralus.kusto.windows.net)")
    parser.add_argument("database", help="Database name")
    args = parser.parse_args()

    print(f"Cluster: {args.cluster_url}")
    print(f"Database: {args.database}")
    print()

    client = create_client(args.cluster_url)

    try:
        create_table(client, args.database)
        ingest_data(client, args.database)
        # Small delay for inline ingestion to settle
        time.sleep(2)
        query_data(client, args.database)
        drop_cmd = f".drop table {TABLE_NAME} ifexists"
        client.execute_mgmt(args.database, drop_cmd)
    except Exception as e:
        print(f"\nError: {e}", file=sys.stderr)
        sys.exit(1)
    finally:
        client.close()

    print("\nDone.")


if __name__ == "__main__":
    main()

Are you adding any additional library that is causing this ?

[ag-ramachandran]

@nikhiltyagi1991 messaging for confirmation, when you get some time