fix(systemd): Update systemd unit files and documentation for Airflow 3.0

airflow-core/docs/howto/run-with-systemd.rst

@@ -27,14 +27,45 @@ In the ``scripts/systemd`` directory, you can find unit files that
 have been tested on Redhat based systems. These files can be used as-is by copying them over to
 ``/usr/lib/systemd/system``.
 
+You can find the latest systemd unit files on GitHub:
+https://github.com/apache/airflow/tree/main/scripts/systemd
+
+Assumptions
+-----------
+
 The following **assumptions** have been made while creating these unit files:
 
 #. Airflow runs as the following ``user:group`` ``airflow:airflow``.
 #. Airflow runs on a Redhat based system.
 
 If this is not the case, appropriate changes will need to be made.
 
+Environment Configuration
+-------------------------
+
 Please **note** that environment configuration is picked up from ``/etc/sysconfig/airflow``.
 
 An example file is supplied within ``scripts/systemd``.
 You can also define configuration at :envvar:`AIRFLOW_HOME` or :envvar:`AIRFLOW_CONFIG`.
+
+Using Virtual Environments
+--------------------------
+
+.. note::
+   If Airflow is installed inside a virtual environment (e.g. ``venv`` or ``conda``), you must update the ``ExecStart`` line in each systemd unit file to activate the virtualenv first.
+
+   Example:
+
+   .. code-block:: ini
+
+       ExecStart=/bin/bash -c 'source /home/airflow/airflow_venv/bin/activate && airflow scheduler'
+
+   Replace ``/home/airflow/airflow_venv/`` with the path to your virtual environment.
+
+New Airflow 3.0 Services
+------------------------
+
+Since Apache Airflow 3.0, additional components have been split out into separate services. The following new unit files are available:
+
+- ``airflow-triggerer.service`` for deferrable task triggering
+- ``airflow-api.service`` for the standalone REST API server

scripts/systemd/airflow-api.service

@@ -0,0 +1,31 @@
+#
+# 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
+# specific language governing permissions and limitations
+# under the License.
+
+[Unit]
+Description=Airflow API Server
+After=network.target
+
+[Service]
+Environment=AIRFLOW_HOME=/home/airflow/airflow_home
+User=airflow
+Group=airflow
+Restart=always
+ExecStart=/bin/bash -c 'source /home/airflow/airflow_venv/bin/activate && airflow api'
+
+[Install]
+WantedBy=multi-user.target

scripts/systemd/airflow-flower.service

@@ -27,6 +27,7 @@ User=airflow
 Group=airflow
 Type=simple
 ExecStart=/bin/airflow celery flower
+ExecStart=/bin/bash -c 'source /home/airflow/airflow_venv/bin/activate && airflow celery flower'
 Restart=on-failure
 RestartSec=5s
 

scripts/systemd/airflow-kerberos.service

@@ -26,7 +26,7 @@ EnvironmentFile=/etc/sysconfig/airflow
 User=airflow
 Group=airflow
 Type=simple
-ExecStart=/bin/airflow kerberos
+ExecStart=/bin/bash -c 'source /home/airflow/airflow_venv/bin/activate && kerberos'
 Restart=on-failure
 RestartSec=5s
 

scripts/systemd/airflow-scheduler.service

@@ -26,7 +26,7 @@ EnvironmentFile=/etc/sysconfig/airflow
 User=airflow
 Group=airflow
 Type=simple
-ExecStart=/bin/airflow scheduler
+ExecStart=/bin/bash -c 'source /home/airflow/airflow_venv/bin/activate && airflow scheduler'
 Restart=always
 RestartSec=5s
 

scripts/systemd/airflow-triggerer.service

@@ -0,0 +1,31 @@
+#
+# 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
+# specific language governing permissions and limitations
+# under the License.
+
+[Unit]
+Description=Airflow Triggerer
+After=network.target
+
+[Service]
+Environment=AIRFLOW_HOME=/home/airflow/airflow_home
+User=airflow
+Group=airflow
+Restart=always
+ExecStart=/bin/bash -c 'source /home/airflow/airflow_venv/bin/activate && airflow triggerer'
+
+[Install]
+WantedBy=multi-user.target

scripts/systemd/airflow-webserver.service

@@ -26,7 +26,7 @@ EnvironmentFile=/etc/sysconfig/airflow
 User=airflow
 Group=airflow
 Type=simple
-ExecStart=/bin/airflow webserver --pid /run/airflow/webserver.pid
+ExecStart=/bin/bash -c 'source /home/airflow/airflow_venv/bin/activate && airflow webserver --pid /run/airflow/webserver.pid'
 Restart=on-failure
 RestartSec=5s
 PrivateTmp=true

scripts/systemd/airflow-worker.service

@@ -26,7 +26,7 @@ EnvironmentFile=/etc/sysconfig/airflow
 User=airflow
 Group=airflow
 Type=simple
-ExecStart=/bin/airflow celery worker
+ExecStart=/bin/bash -c 'source /home/airflow/airflow_venv/bin/activate && airflow celery worker'
 Restart=on-failure
 RestartSec=10s