__main__.py

#!/usr/bin/env python
# PYTHON_ARGCOMPLETE_OK
#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
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# under the License.
"""Main executable module."""

from __future__ import annotations

import os
from argparse import Namespace

import argcomplete

# The configuration module initializes and validates the conf object as a side effect the first
# time it is imported. If it is not imported before importing the settings module, the conf
# object will then be initted/validated as a side effect of it being imported in settings,
# however this can cause issues since those modules are very tightly coupled and can
# very easily cause import cycles in the conf init/validate code (since downstream code from
# those functions likely import settings).
# Therefore importing configuration early (as the first airflow import) avoids
# any possible import cycles with settings downstream.
from airflow import configuration
from airflow.cli import cli_parser
from airflow.configuration import AirflowConfigParser, write_webserver_configuration_if_needed
from airflow.exceptions import AirflowException


def main():
    conf = configuration.conf
    if conf.get("core", "security") == "kerberos":
        os.environ["KRB5CCNAME"] = conf.get("kerberos", "ccache")
        os.environ["KRB5_KTNAME"] = conf.get("kerberos", "keytab")
    parser = cli_parser.get_parser()
    argcomplete.autocomplete(parser)
    args = parser.parse_args()
    if args.subcommand not in ["lazy_loaded", "version"]:
        # Here we ensure that the default configuration is written if needed before running any command
        # that might need it. This used to be done during configuration initialization but having it
        # in main ensures that it is not done during tests and other ways airflow imports are used
        from airflow.configuration import write_default_airflow_configuration_if_needed

        conf = write_default_airflow_configuration_if_needed()
        if args.subcommand in ["webserver", "internal-api", "worker"]:
            write_webserver_configuration_if_needed(conf)
    configure_internal_api(args, conf)

    args.func(args)


def configure_internal_api(args: Namespace, conf: AirflowConfigParser):
    if conf.getboolean("core", "database_access_isolation", fallback=False):
        if args.subcommand in ["worker", "dag-processor", "triggerer", "run"]:
            # Untrusted components
            if "AIRFLOW__DATABASE__SQL_ALCHEMY_CONN" in os.environ:
                # make sure that the DB is not available for the components that should not access it
                os.environ["AIRFLOW__DATABASE__SQL_ALCHEMY_CONN"] = "none://"
                conf.set("database", "sql_alchemy_conn", "none://")
            from airflow.api_internal.internal_api_call import InternalApiConfig

            InternalApiConfig.set_use_internal_api(args.subcommand)
        else:
            # Trusted components (this setting is mostly for Breeze where db_isolation and DB are both set
            db_connection_url = conf.get("database", "sql_alchemy_conn")
            if not db_connection_url or db_connection_url == "none://":
                raise AirflowException(
                    f"Running trusted components {args.subcommand} in db isolation mode "
                    f"requires connection to be configured via database/sql_alchemy_conn."
                )
            from airflow.api_internal.internal_api_call import InternalApiConfig

            InternalApiConfig.set_use_database_access(args.subcommand)


if __name__ == "__main__":
    main()