62 lines
1.5 KiB
Markdown
62 lines
1.5 KiB
Markdown
---
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title: Use Events for Workflow Status Publishing
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impact: MEDIUM
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impactDescription: Enables real-time workflow status monitoring
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tags: events, set_event, get_event, status
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---
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## Use Events for Workflow Status Publishing
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Workflows can publish key-value events that clients can read. Events are persisted and useful for status updates.
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**Incorrect (no way to monitor progress):**
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```python
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@DBOS.workflow()
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def long_workflow():
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step_one()
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step_two() # Client can't see progress
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step_three()
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return "done"
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```
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**Correct (publishing events):**
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```python
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@DBOS.workflow()
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def long_workflow():
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DBOS.set_event("status", "starting")
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step_one()
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DBOS.set_event("status", "step_one_complete")
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step_two()
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DBOS.set_event("status", "step_two_complete")
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step_three()
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DBOS.set_event("status", "finished")
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return "done"
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# Client code to read events
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@app.post("/start")
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def start_workflow():
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handle = DBOS.start_workflow(long_workflow)
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return {"workflow_id": handle.get_workflow_id()}
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@app.get("/status/{workflow_id}")
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def get_status(workflow_id: str):
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status = DBOS.get_event(workflow_id, "status", timeout_seconds=0) or "not started"
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return {"status": status}
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```
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Get all events from a workflow:
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```python
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all_events = DBOS.get_all_events(workflow_id)
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# Returns: {"status": "finished", "other_key": "value"}
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```
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Events can be called from `set_event` from workflows or steps.
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Reference: [Workflow Events](https://docs.dbos.dev/python/tutorials/workflow-communication#workflow-events)
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