Ensure singleton use of DagBag across all API requests
#50447
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kaxil
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jason810496
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LGTM, thanks! Initializing DagBag during FastAPI's lifespan event is a thread-safe and cleaner way to achieve a singleton pattern.
I had considered using airflow.utils.singleton.Singleton for this, but the current Singleton utility is not thread-safe. Adding a thread-level lock might introduce performance issues, especially if DagBag initialization takes a long time and blocks other threads.
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Previously, DagBag was injected via onlyFastAPI dependency as part of the refactor in apache#50372 , but a new instance was created for each request. This change updates the dependency to resolve DagBag from `app.state`, ensuring it is only instantiated once at startup while keeping benefits of FastAPI dependency.
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Previously, DagBag was injected via onlyFastAPI dependency as part of the refactor in #50372 , but a new instance was created for each request. This change updates the dependency to resolve DagBag from `app.state`, ensuring it is only instantiated once at startup while keeping benefits of FastAPI dependency. (cherry picked from commit 3b49f9d)
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Previously, DagBag was injected via onlyFastAPI dependency as part of the refactor in #50372 , but a new instance was created for each request. This change updates the dependency to resolve DagBag from `app.state`, ensuring it is only instantiated once at startup while keeping benefits of FastAPI dependency. (cherry picked from commit 3b49f9d)
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Previously, DagBag was injected via onlyFastAPI dependency as part of the refactor in apache#50372 , but a new instance was created for each request. This change updates the dependency to resolve DagBag from `app.state`, ensuring it is only instantiated once at startup while keeping benefits of FastAPI dependency.
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Previously, DagBag was injected via onlyFastAPI dependency as part of the refactor in #50372, but a new instance was created for each request. This change updates the dependency to resolve DagBag from
app.state, ensuring it is only instantiated once at startup while keeping benefits of FastAPI dependency.^ Add meaningful description above
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