Airflow Custom Hooks

You should create hook only in the execute method or any method which is called from execute.

Airflow custom hooks. This however overcomplicates the issue and leads to confusion for many people. For example this function re routes the task to execute in a different queue during retries. See the notice file distributed with this work for additional information regarding copyright ownership. To mutate the task instance before the task execution you can define a task instance mutation hook function in airflow local settings py that mutates the task instance.

There is however some confusion on the best way to implement them. Custom hooks and operators are a powerful way to extend airflow to meet your needs. Queue retry queue cluster policies for custom task checks. The hook retrieves the auth parameters such as username and password from airflow backend and passes the params to the airflow hooks base hook basehook get connection.

In my custom operators which use my custom hooks i import them like my operator py from hooks my hook import myhook then in my dag files i can do sample dag py from airflow operators plugin name import myoperator this also facilitates testing since the imports within the custom classes are relative to the sub modules within the folder plugins. The asf licenses this file to you under the apache license version 2 0 the license. Source code for airflow hooks hive hooks coding. Unlike a react component a custom hook doesn t need to have a specific signature.

Package contents airflow hooks hooks source airflow hooks airflow importer source airflow hooks integrate plugins source integrate plugins to the context. Hooks need to be derived from either the base hook class airflow hooks base hook basehook or one of the existing hooks that are built into airflow such as airflow hooks dbapi hook dbapihook. We can decide what it takes as arguments and what if anything it should return. Utf 8 licensed to the apache software foundation asf under one or more contributor license agreements.

In other words it s just like a normal function. Just like in a component make sure to only call other hooks unconditionally at the top level of your custom hook. Was this entry helpful. Its name should always start with use so that you can tell at.

Suggest a change on this page. I wonder if i can omit the init py file.