Personally, I prefer the interface approach as it aligns better with
enterprise-grade software. That said, I am also fine with proceeding via
the _cmd and _secret route for the time being.

Thanks,
Sumit

On Fri, Oct 30, 2026 at 11:47 AM Shahar Epstein <[email protected]> wrote:

> Hey Sameer and everyone,
>
> +1 to the revised scope in #74915.
>
> The need has come up several times: #61645, discussion #59799, #63928, and
> #71111 all asked for this in different forms. I think it’s a good time to
> add the feature.
>
> I think it can proceed without an AIP for the following reasons:
>
> 1. The revised scope adds no pluggable abstraction, config entry, API, or
> DB migration. Reloading uses the existing dag_bundle_config_list format,
> supplied through Airflow’s existing _cmd / _secret mechanism. The PR makes
> that mechanism available for this key by marking it as sensitive.
> 2. It’s opt-in. A value set through a plain environment variable or
> airflow.cfg keeps today’s startup-only behavior. _CMD / _SECRET were not
> available for this key before, so no existing deployment will start
> reloading without an explicit change.
> 3. The trust boundary does not change. Bundle definitions remain under the
> Deployment Manager’s control; users cannot change them through Airflow.
>
> Neither of the two previous threads has received a reply yet. Sameer, I
> suggest waiting few more days (let's say until Monday, Nov. 2nd) to give a
> chance for others to comment on this thread, and following up with a [LAZY
> CONSENSUS] thread on the revised scope if there are no responses by then,
> or there's consensus.
>
> Disclosure: I helped Sameer narrow the scope and I’m reviewing the PR, so
> please take that into account when weighing my comment.
>
>
> Shahar
>
> On Sun, Oct 25, 2026 at 12:33 PM Sameer Raj via dev <
> [email protected]>
> wrote:
>
> > Hi everyone!
> >
> > Following up on this discussion, I would like to share the revised scope.
> > The earlier proposal included a DagBundleProvider abstraction. I have
> > dropped that abstraction from the current work. It can be proposed
> > separately through a future AIP if needed. The new PR is limited to
> > reloading the existing [dag_processor] dag_bundle_config_list through
> > Airflow’s_CMD or_SECRET mechanism:
> >
> > https://github.com/apache/airflow/pull/74915
> >
> > Thanks to Shahar for helping me narrow down the scope and for reviewing
> the
> > approach.
> >
> > In our use case, we need to manage more than 500 DAG bundles, with
> > additions being automated. Restarting or redeploying Airflow processes
> > whenever a bundle is added makes this difficult. We want to fetch the
> > bundle list from an internal API. A deployment managed command can call
> > that API and return the same JSON list already accepted by
> > dag_bundle_config_list. The command could also read a file, or the list
> > could come from a secrets backend.
> >
> > The DAG processor checks for changes at
> > bundle_refresh_check_interval. Users do not need to change their
> > configuration unless they want to enable reload. Users only need to
> > configure _CMD or _SECRET if they want reload.
> >
> > The expected behavior is:
> >
> >    - When a bundle is added, the Dag processor discovers it and starts
> >    processing its files. Existing bundle instances are reused.
> >    - When a bundle is removed, the processor stops processing it. An
> >    unfiltered processor (without --bundle-name) marks it inactive, and
> the
> >    existing stale DAG scan marks its dags stale. A successful read
> > containing
> >    [] removes all bundles.
> >    - Failed commands, unavailable secrets, wrong configs, invalid new
> >    classpaths, and blank reads keep the last accepted list in that
> process.
> >    The source must return the complete list. Commands should return a non
> > zero
> >    exit on failure, rather than returning [].
> >    - A fresh process has no previous list to fall back to. Invalid or
> >    unavailable configuration prevents startup. A valid [] starts with no
> >    bundles.
> >    - Processors started with --bundle-name stop processing removed
> bundles
> >    locally, but never deactivate missing bundles globally (retaining
> > existing
> >    behaviour). A processor that sees the complete list is needed for
> global
> >    deactivation.
> >    - Multiple Dag processors may see changes at different times (due to
> >    variance in the refresh interval). Each unfiltered processor
> reconciles
> >    bundle in the database even when its own list has not changed, so it
> can
> >    correct a stale write from another processor. They eventually converge
> > when
> >    surviving processors see the same list and continue reconciling.
> >
> > All components, i.e. the DAG processor and workers that resolve bundles
> > need access to the configuration source. Existing Dag runs should finish
> > before removing a bundle if those runs need to complete, since tasks and
> > callbacks can still need its definition.
> >
> > For v1, changing an existing bundle’s definition is rejected, and the
> last
> > accepted list is retained. This includes changing tracking_ref or
> classpath
> > etc. Such a change requires a new bundle name or restarting the affected
> > components. New commits on the already configured branch continue to be
> > picked up through the existing bundle refresh behavior. Supporting
> changes
> > to an existing bundle definition can be added later incase required!
> >
> > There is also an optional DagFileParseRequest.bundle_config field
> > containing the accepted importer settings and team ownership. It allows
> the
> > parsing process (to parse the DAG) to use the configuration accepted by
> its
> > parent, without reading the command or secrets backend again and
> > potentially seeing a different list. This does change the parser protocol
> > but the compatibility handling is included in the PR
> >
> > The dag_bundle_config_list option is marked sensitive: true to enable
> _CMD
> > and _SECRET. This also means the option is hidden in configuration views
> > that hide sensitive values. The Deployment Manager continues to control
> the
> > command or secrets backend and its credentials. No API for creating or
> > changing bundle definitions is added.
> >
> > Related discussions by various users:
> >
> >    - Runtime bundle management:
> >    https://github.com/apache/airflow/issues/61645
> >    - Automatic bundle configuration loading:
> >    https://github.com/apache/airflow/discussions/59799
> >    - Earlier file-based reload PR:
> >    https://github.com/apache/airflow/pull/71111
> >    - Earlier dev-list discussion on runtime reload:
> >    https://lists.apache.org/thread/co0z6yxc1g6ctqqmt7rdszjhjsq0w2hx
> >
> > I would appreciate feedback on this revised scope, proposed flow and the
> > state v1 limitation.
> >
> > Thanks,
> > Sameer Raj
> >
> > On Wed, Sep 23, 2026 at 3:35 PM Sameer Raj <[email protected]> wrote:
> >
> > > Hi everyone!
> > > I would like to discuss adding support for dynamically discovering new
> > DAG
> > > bundle configurations without requiring Airflow restarts. (following up
> > on
> > > comment:
> > > https://github.com/apache/airflow/issues/61645#issuecomment-5017217627
> )
> > >
> > > There's also multiple PRs/discussion going over for the same feature:
> > > - Runtime CRUD proposal:
> > >   https://github.com/apache/airflow/issues/61645
> > > - Automatic bundle configuration loading:
> > >   https://github.com/apache/airflow/discussions/59799
> > > - File-based hot-reload PR:
> > >   https://github.com/apache/airflow/pull/63928
> > > - Add dynamic DAG bundle configuration from file path
> > >   https://github.com/apache/airflow/pull/71111
> > >
> > > *The Problem:*
> > >
> > > Today, Dag bundles are configured through [dag_processor]
> > > dag_bundle_config_list. DagBundlesManager loads this configuration when
> > > the process starts, and the Dag processor uses the same bundle list.
> > >
> > > This becomes operationally difficult for deployments that manage many
> > > bundles and regularly add (or remove) them. Each configuration change
> > > currently requires restarting or redeploying the affected Airflow
> > processes.
> > >
> > > *Proposal*
> > >
> > > The proposal has two parts:
> > >
> > > First, introduce a DagBundleProvider abstraction into
> DagBundlesManager.
> > > It would allow Airflow to discover the bundle configurations construct
> > > bundles accordingly. Thus, the responsibility to fetch bundles is
> passed
> > on
> > > to DagBundleProvider by DagBundleManager.
> > >
> > > The configured class could obtain bundle information from a file, blob
> > > storage, an internal service, or another deployment-specific source
> (and
> > > this will decouple Airflow being aware of the source). Airflow would
> > define
> > > the class contract without adding direct support for every possible
> > source.
> > >
> > > The existing dag_bundle_config_list would remain the default
> > > implementation, so current deployments would keep the same behavior.
> > >
> > > Second, allow the Dag processor to periodically ask the configured
> class
> > > for the latest bundle configurations from its existing processing loop.
> > >
> > > When a bundle is added, the Dag processor would discover it and begin
> > > processing its files. When a bundle is removed, the Dag processor would
> > > stop processing it and use the existing removed-file handling for its
> > Dags.
> > >
> > > Each Dag processor performs this reconciliation periodically.
> Processors
> > > may observe a change at slightly different times, but they will
> converge
> > on
> > > the configuration returned by the provider.
> > >
> > > *Why use a configurable class?*
> > >
> > > In this comment
> > > <
> https://github.com/apache/airflow/issues/61645#issuecomment-5017217627
> > >,
> > > Jarek asked why a custom dynamic manager would be preferable to
> managing
> > > Airflow configuration dynamically.
> > >
> > > On this, having this abstraction can allow users to implement their way
> > by
> > > which they plan to reload the configs, for example, fetch from external
> > > system etc. Also changing the environment variable for bundle list wont
> > > automatically reload the bundles, and the capability need to be built
> for
> > > the same.
> > >
> > > *Security*
> > >
> > > The security implications of changing bundle definitions through the
> > > Airflow API were raised in issue #61645
> > > <
> https://github.com/apache/airflow/issues/61645#issuecomment-4212433885
> > >.
> > >
> > > This proposal keeps management of bundle definitions within the
> existing
> > > Deployment Manager trust boundary.
> > >
> > >    - The Deployment Manager selects and deploys the DagBundleProvider
> > >    implementation.
> > >    - The Deployment Manager controls access to its configuration
> source.
> > >    - Credentials and authorization for that source remain deployment
> > >    managed.
> > >    - The Airflow API does not expose operations for creating or
> changing
> > >    bundle definitions.
> > >    - No new Airflow user role is introduced for managing bundles.
> > >
> > > *Compatibility*
> > >
> > > The existing dag_bundle_config_list remains the default source and
> keeps
> > > its current behavior.
> > >
> > > *Value Addition*
> > >
> > > Multiple users have raised PR/discuss thread on Airflow Github for the
> > > same, and this feature will be very useful for the community who are
> > > managing multiple bundles. Reference for the threads is shared above.
> > >
> > > *Current work*
> > >
> > > I have split the work into two PRs so each part can be reviewed
> > separately:
> > >
> > >    - Provider abstraction:
> > >    https://github.com/apache/airflow/pull/73209
> > >    - Runtime configuration reload:
> > >    https://github.com/apache/airflow/pull/73217
> > >
> > > I would appreciate feedback on this!
> > >
> > > Thanks,
> > > Sameer Raj
> > >
> > >
> > >
> > >
> > >
> >
>

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