Hi Everyone, I have an enhancement proposal for the REST API service. This is based on the observations that Airflow users want to be able to access Airflow more easily as a platform service.
The motivation comes from the following use cases: 1. Users like data scientists want to iterate over data quickly with interactive feedback in minutes, e.g. managing data pipelines inside Jupyter Notebook while executing them in a remote airflow cluster. 2. Services targeting specific audiences can generate DAGs based on inputs like user command or external triggers, and they want to be able to submit DAGs programmatically without manual intervention. I believe such use cases would help promote Airflow usability and gain more customer popularity. The existing DAG repo brings considerable overhead for such scenarios, a shared repo requires offline processes and can be slow to rollout. The proposal aims to provide an alternative where a DAG can be transmitted online and here are some key points: 1. A DAG is packaged individually so that it can be distributable over the network. For example, a DAG may be a serialized binary or a zip file. 2. The Airflow REST API is the ideal place to talk with the external world. The API would provide a generic interface to accept DAG artifacts and should be extensible to support different artifact formats if needed. 3. DAG persistence needs to be implemented since they are not part of the DAG repository. 4. Same behavior for DAGs supported in API vs those defined in the repo, i.e. users write DAGs in the same syntax, and its scheduling, execution, and web server UI should behave the same way. Since DAGs are written as code, running arbitrary code inside Airflow may pose high security risks. Here are a few proposals to stop the security breach: 1. Accept DAGs only from trusted parties. Airflow already supports pluggable authentication modules where strong authentication such as Kerberos can be used. 2. Execute DAG code as the API identity, i.e. A DAG created through the API service will have run_as_user set to be the API identity. 3. To enforce data access control on DAGs, the API identity should also be used to access the data warehouse. We shared a demo based on a prototype implementation in the summit and some details are described in this ppt <https://drive.google.com/file/d/1luDGvWRA-hwn2NjPoobis2SL4_UNYfcM/view>, and would love to get feedback and comments from the community about this initiative. thanks Mocheng
