7e5abd504f
Add three DBOS SDK skills with reference documentation for building reliable, fault-tolerant applications with durable workflows. Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
54 lines
1.3 KiB
Markdown
54 lines
1.3 KiB
Markdown
---
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title: Use Steps for External Operations
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impact: HIGH
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impactDescription: Steps enable recovery by checkpointing results
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tags: step, external, api, checkpoint
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---
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## Use Steps for External Operations
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Any function that performs complex operations, accesses external APIs, or has side effects should be a step. Step results are checkpointed, enabling workflow recovery.
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**Incorrect (external call in workflow):**
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```python
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import requests
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@DBOS.workflow()
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def my_workflow():
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# External API call directly in workflow - not checkpointed!
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response = requests.get("https://api.example.com/data")
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return response.json()
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```
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**Correct (external call in step):**
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```python
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import requests
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@DBOS.step()
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def fetch_data():
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response = requests.get("https://api.example.com/data")
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return response.json()
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@DBOS.workflow()
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def my_workflow():
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# Step result is checkpointed for recovery
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data = fetch_data()
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return data
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```
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Step requirements:
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- Inputs and outputs must be serializable
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- Should not modify global state
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- Can be retried on failure (configurable)
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When to use steps:
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- API calls to external services
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- File system operations
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- Random number generation
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- Getting current time
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- Any non-deterministic operation
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Reference: [DBOS Steps](https://docs.dbos.dev/python/tutorials/step-tutorial)
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