Presto connection

Connect a task to a Presto coordinator to run distributed SQL over a managed Leoflow Connection. Presto is the upstream project Trino forked from; the Connection shape is identical, only the scheme and hook differ.

Declare the provider

# leoflow.yaml
dag_id: presto_query
connectors:
  - presto

URI shape

presto://<login>:<password>@<host>:<port>/<catalog>

The control plane builds this from the Connection’s fields and exports it as AIRFLOW_CONN_<CONN_ID>. Reserved characters in the password are percent-escaped; PrestoHook un-escapes them on the way out.

Fields the UI asks for

Field	Required	Notes
Conn Id	yes	e.g. `presto_default`. Exported as `AIRFLOW_CONN_PRESTO_DEFAULT`.
Conn Type	yes	`presto`.
Host	yes	Coordinator hostname, e.g. `presto.example.com`.
Port	usually `8080`	Coordinator HTTP port (`8443` for TLS).
Login	yes	Presto user, e.g. `etl_user`.
Password	optional	Password for `PASSWORD` auth. Encrypted at rest (ADR 0019).
Schema	optional	Default catalog, e.g. `hive`.
Extra	optional	JSON: `{"protocol":"https","catalog":"hive","schema":"default"}`.

Example DAG

# dag.py
from airflow.sdk import DAG, task


@task
def count_rows():
    from airflow.providers.presto.hooks.presto import PrestoHook

    hook = PrestoHook(presto_conn_id="presto_default")
    rows = hook.get_records("SELECT count(*) FROM hive.default.events")
    print("event count:", rows[0][0])


with DAG("presto_query", schedule=None, catchup=False, tags=["example"]):
    count_rows()

# leoflow.yaml
schema_version: "1.0"
dag_id: presto_query
python_version: "3.12"
connectors:
  - presto
connections:
  - presto_default

Security notes

TLS: set the coordinator port to 8443 and Extra = {"protocol":"https"}. Never run PASSWORD auth over plain HTTP.
Least privilege: scope the Presto user to the catalogs the DAG needs.
Never log AIRFLOW_CONN_PRESTO_DEFAULT; it carries the password.

ADR 0019 — secret encryption at rest.
ADR 0021 — agent secret delivery (AIRFLOW_CONN_<CONN_ID>).
TestPrestoConnectionURIShapeIntegration — chain-of-custody delivery test.
Trino connection — the modern fork of Presto.

Last modified August 24, 2026: docs: cut over to Hugo + Docsy (Node 22 deploy, CI-verified) (#721) (253e9d9)