potiuk commented on code in PR #36513: URL: https://github.com/apache/airflow/pull/36513#discussion_r1440802365
########## docs/apache-airflow/core-concepts/overview.rst: ########## @@ -18,49 +18,151 @@ Architecture Overview ===================== -Airflow is a platform that lets you build and run *workflows*. A workflow is represented as a :doc:`DAG <dags>` (a Directed Acyclic Graph), and contains individual pieces of work called :doc:`tasks`, arranged with dependencies and data flows taken into account. +Airflow is a platform that lets you build and run *workflows*. A workflow is represented as a +:doc:`DAG <dags>` (a Directed Acyclic Graph), and contains individual pieces of work called +:doc:`tasks`, arranged with dependencies and data flows taken into account. .. image:: ../img/edge_label_example.png :alt: An example Airflow DAG, rendered in Graph -A DAG specifies the dependencies between Tasks, and the order in which to execute them and run retries; the Tasks themselves describe what to do, be it fetching data, running analysis, triggering other systems, or more. +A DAG specifies the dependencies between Tasks, and the order in which to execute them and run retries; +the Tasks themselves describe what to do, be it fetching data, running analysis, triggering other systems, +or more. -An Airflow installation generally consists of the following components: +Airflow components +------------------ -* A :doc:`scheduler <../administration-and-deployment/scheduler>`, which handles both triggering scheduled workflows, and submitting :doc:`tasks` to the executor to run. +Required components +................... -* An :doc:`executor <executor/index>`, which handles running tasks. In the default Airflow installation, this runs everything *inside* the scheduler, but most production-suitable executors actually push task execution out to *workers*. +Minimal Airflow installation consists of the following components: -* A *triggerer*, which executes deferred tasks - executed in an async-io event loop. +* A :doc:`scheduler <../administration-and-deployment/scheduler>`, which handles both triggering scheduled + workflows, and submitting :doc:`tasks` to the executor to run. The :doc:`executor <executor/index>`, is + a configuration property of the *scheduler*, not a separate component and runs within the scheduler + process. There are several executors available out of the box, and you can also write your own. -* A *webserver*, which presents a handy user interface to inspect, trigger and debug the behaviour of DAGs and tasks. +* A *webserver*, which presents a handy user interface to inspect, trigger and debug the behaviour of + DAGs and tasks. -* A folder of *DAG files*, read by the scheduler and executor (and any workers the executor has) +* A folder of *DAG files*, is read by the *scheduler* to figure out what tasks to run and when and to + run them. -* A *metadata database*, used by the scheduler, executor and webserver to store state. +* A *metadata database*, used by the *scheduler*, and *webserver* to store state of workflows and tasks. + Setting up a metadata database is described in :doc:`/howto/set-up-database` and is required for + Airflow to work. +Optional components +................... -Basic airflow architecture --------------------------- +There are also some optional components that are not present in the basic installation Review Comment: Nice. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@airflow.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
