Hi Jarek, thanks a lot for the feedback and I understand security is a major concern and I would like to discuss more here. AIP-5/AIP-20 share the same goal to be able to ship DAGs individually but there are some differences and I'd be happy to align them together if that is possible.
For the security concern, is it true that "access DAG files" means loading DAG code? If that's correct, the proposal will not introduce it inside the api/web server, the DAG could be serialized in API client and DAG code/files through the API would be handled as a blob but it needs to be persisted and meta data inside DB needs to be updated. For task execution in worker, it can be better isolated with current internal API initiative, and I have missed discussion in AIP-5 and maybe you could help educate me here, what are the security differences between DAGs pushed to API vs DAGs pulled from remote repositories in AIP-5? Besides security, one difference between AIP-5/AIP-20 and API is that AIP-5/AIP-20 design is only about reading and does not manage DAG creation inside Airflow, I understand if this is currently by design to keep Airflow off the storage responsibility and instead rely on external service/process to manage and supply DAG repo, but it brings extra complexity, for example, this external service/process needs to understand Airflow and prevent duplicate dag_id. The API proposal could support it natively with access to the DB, and can synchronously return status to client. If this can be alternatively included inside AIP-5 that'd be great. thanks Mocheng On Wed, Aug 10, 2022 at 5:27 AM Jarek Potiuk <ja...@potiuk.com> wrote: > This has been discussed several times, and I think you should rather take > a look and focus on those proposals already there: > > * https://cwiki.apache.org/confluence/display/AIRFLOW/AIP-20+DAG+manifest > * > https://cwiki.apache.org/confluence/display/AIRFLOW/AIP-5+Remote+DAG+Fetcher > > Both proposals are supposed to address various caveats connected with > trying to submit Python DAG via API. > > * DAG manifest was a proposal on how to add meta-data to "limit" dag to > know what kind of other resources are needed for it to run > * Remote DAG Fetcher on the other hand would allow a user to use various > mechanisms to "Pull the data" (or if you develop your fetcher in the way to > allow Push, it would also allow Push model to work if we add some async > notifications there). > > I personally think using rest API to submit DAGs is a bad idea because it > is against the current security model of Airflow where Webserver (and also > REST API) has not only "READ ONLY" access to DAGs, but also has actually > "NO ACCESS" to DAGs whatsoever. > Currently, the webserver (i.e. API server) has no physical access to any > resources where executable DAG code is accessed and can be not only changed > but read directly. It only accesses the DB. Changing that is a huge change > in the security model. Actually it goes backwards to the changes we've > implemented in Airflow 1.10 initially and leaving that as the only option > in Airflow 2 (introducing DAG serialisation) where we specifically put a > lot of effort to remove the need for the webserver to access DAG files - > and security model we chose was the main driver for that. > > Making it possible to submit a new executable code via REST API of Airflow > would significantly increase dangers of exposing the API and make it an > order of magnitude more serious point of attack for an attacker. Basically > you are allowing the person who has access to API to submit an executable > code that should be executable by DAG file processor and worker. > Due to this - I don't think using REST API for that is a good idea and for > me this is no-go. > > However both AIP-5 and AIP-20 (when discussed, approved and implemented) > should nicely address the user requirement you have, without compromising > the security of the APIs - so I'd heartily recommend you to take a look > there and see if maybe you could take a lead in those discussions and > finalising them. Currently there is no-one actively working on those two > AIPs. but I think there are at least a few people who would like to be > involved if there is someone who will lead this effort (myself included). > > J. > > > On Wed, Aug 10, 2022 at 1:46 AM Mocheng Guo <gmca...@gmail.com> wrote: > >> 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 >> >
