- Regular probes gather metrics and status.
- Analysis task decides whether to restart or escalate.
- Actions are idempotent and logged for audit.
Example considerations:
- Use exponential backoff and circuit breakers to avoid flapping.
- Require higher privilege actions (rollback) to pass additional checks or approvals.
Example 4 — Content pipeline for marketing
Problem: Marketing needs images resized, watermarked, and uploaded to CDN when designers drop files into a shared storage.
Solution:
- Tasks: watch_bucket, process_image (resize + watermark), optimize, upload_cdn, notify_team.
- Use event-driven triggers (object-created events) to start flows.
Sample processing task:
from pygear import Task from PIL import Image class ProcessImage(Task): def run(self, file_path): img = Image.open(file_path) img = img.resize((1200, 800)) watermark = Image.open("assets/wm.png") img.paste(watermark, (10, 10), watermark) out = file_path.replace("/incoming", "/processed") img.save(out, optimize=True, quality=85) return out
Benefits:
- Designers get near-instant feedback as assets appear on the CDN.
- Versioned outputs and retry on transient upload failures.
Example 5 — Automated test-run orchestration
Problem: Run fast unit tests locally and a broader test matrix on CI with parallelization and flaky-test handling.
Solution:
- Tasks: discover_tests, run_tests(shard), collect_results, rerun_flaky.
- Orchestrate parallel runs across workers; collect and aggregate JUnit XML.
Key points:
- Use sharding and sampling to reduce latency.
- Implement rerun logic for flaky tests with limits to avoid masking real failures.
Best practices when building pyGear workflows
- Keep tasks small and focused — easier to test and reuse.
- Use idempotent operations so flows can be retried safely.
- Store secrets in a secrets manager; avoid hardcoding credentials.
- Add observability: structured logs, metrics, and traces for each task.
- Write unit tests for task logic and integration tests for flows.
- Use feature flags or a manual approval step for destructive actions.
Testing, deployment, and CI
- Unit-test tasks using mocks for external services.
- Use a lightweight local runner for development and scale to a worker cluster for production.
- Deploy pyGear workflows as versioned packages or keep flows in a centralized repo with release tags.
- Schedule flows with cron-like scheduler or integrate with a CI pipeline for event-driven runs.
Monitoring and debugging
- Emit structured events for start/finish/error of each task.
- Capture task inputs/outputs (or hashes) for reproducibility; avoid logging secrets.
- Provide a retry and dead-letter mechanism for failed tasks.
- Use tracing (OpenTelemetry) to follow a request through multiple tasks.
Conclusion
pyGear turns repetitive processes into readable, testable Python code. By composing small tasks, integrating with existing services, and following safety patterns like idempotency and observability, teams can automate a broad range of workflows—from ETL and CI orchestration to content pipelines and self-healing infrastructure. The examples above provide templates you can adapt to your environment and scale as needs grow.
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