prefect.server.services.loop_service
¶
The base class for all Prefect REST API loop services.
LoopService
¶
Loop services are relatively lightweight maintenance routines that need to run periodically.
This class makes it straightforward to design and integrate them. Users only need to
define the run_once
coroutine to describe the behavior of the service on each loop.
Source code in /home/runner/work/docs/docs/prefect_source/src/prefect/server/services/loop_service.py
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run_once
async
¶
Represents one loop of the service.
Users should override this method.
To actually run the service once, call LoopService().start(loops=1)
instead of LoopService().run_once()
, because this method will not invoke setup
and teardown methods properly.
Source code in /home/runner/work/docs/docs/prefect_source/src/prefect/server/services/loop_service.py
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start
async
¶
Run the service loops
time. Pass loops=None to run forever.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
loops |
int
|
the number of loops to run before exiting. |
None
|
Source code in /home/runner/work/docs/docs/prefect_source/src/prefect/server/services/loop_service.py
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stop
async
¶
Gracefully stops a running LoopService and optionally blocks until the service stops.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
block |
bool
|
if True, blocks until the service is finished running. Otherwise it requests a stop and returns but the service may still be running a final loop. |
True
|
Source code in /home/runner/work/docs/docs/prefect_source/src/prefect/server/services/loop_service.py
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run_multiple_services
async
¶
Only one signal handler can be active at a time, so this function takes a list of loop services and runs all of them with a global signal handler.
Source code in /home/runner/work/docs/docs/prefect_source/src/prefect/server/services/loop_service.py
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