Cloud Composer versioning overview

This page describes how Cloud Composer versioning works.

Versioning enables you to select a Cloud Composer image version when you create or upgrade an environment.

Cloud Composer images

To run Apache Airflow, Cloud Composer builds Docker images that bundle Airflow releases with other common binaries and Python libraries.

Cloud Composer images include Airflow modifications that are specific to Cloud Composer and unsuitable for the upstream Airflow codebase. The preinstalled packages along with Cloud Composer-specific Airflow changes are referred to collectively as Cloud Composer versions.

Google periodically releases new Cloud Composer images that include new Airflow releases and Cloud Composer improvements.

Airflow version support

Airflow follows the semantical software versioning schema.

For every Cloud Composer version, Cloud Composer supports at least three patch versions of Airflow. Cloud Composer might not support some patch versions of Airflow if there are functional, quality, or performance issues with a specific Airflow version.

For a list of Airflow versions supported in each Cloud Composer version, see the list of Cloud Composer versions.

Version schema

Cloud Composer image versioning schema captures Cloud Composer and Airflow versions:

composer-a.b.c-airflow-x.y.z

Where

• composer-a.b.c is the version of Cloud Composer-managed customizations
• airflow-x.y.z is the Airflow release

Version flags and aliases

Cloud Composer supports Cloud Composer image versions that are pinned to the latest Cloud Composer version.

When you create an Cloud Composer environment, you can use these flags to specify the environment version:

• --image-version, to specify the environment version in the form composer-a.b.c-airflow-x.y.z.
• --airflow-version, to specify the Airflow version in the form x.y.z, which creates the environment using the latest Cloud Composer version and specified Airflow version.

Cloud Composer also supports using the following version aliases:

• composer-latest-airflow-x.y.z specifies an image version with the latest Cloud Composer version.
• composer-a.b.c-airflow-x.y specifies an image version that automatically expands to composer-a.b.c-airflow-x.y.z where z is the latest patch number.
• composer-latest-airflow-x.y specifies an image version with the latest Cloud Composer version that automatically expands to airflow-x.y.z where z is the latest patch number.

Note: Creating a Cloud Composer environment version with composer-latest-airflow-x.y.z does not provide automatic version upgrades. Instead, Cloud Composer resolves the version alias to composer-a.b.c-airflow-x.y.z at creation time.

Version deprecation and support

Google supports Cloud Composer versions for a period of time after the version release. During this period, Cloud Composer environments that use these versions are fully supported.

Cloud Composer version support is defined as follows:

• 0-12 months from the release date: Cloud Composer environments running these versions are fully supported.
• 12-18 months from the release date: Cloud Composer environments running these versions are unsupported except to notify customers about security issues.
• 18+ months from the release date: Cloud Composer environments running these versions are unsupported and entirely user managed.

Note: You can use Cloud Composer versions after the date they are no longer supported. For example, if your environment is based on a Cloud Composer version that is past the support period, the environment still works and you can keep using it. In this case, we recommend you to upgrade your environment to a supported version.

What's next

• See the list of available Cloud Composer versions.
• Create a Cloud Composer environment.
• Upgrade an existing Cloud Composer environment.