StatusNest Worker

Serverless monitoring engine for StatusNest. Two AWS Lambda functions that together handle service health checking, result caching, and database persistence.

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Architecture

EventBridge (every 60s)
        │
        ▼
 monitor Lambda          ← Reads active services from RDS
        │                   Pings each URL (HTTP)
        │                   Sends result to SQS
        ▼
      SQS Queue
        │
        ▼
 processor Lambda        ← Reads SQS messages
                            Writes status + response_time + checked_at to Redis (TTL 90s)
                            Inserts row into service_status table (RDS)

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Functions

monitor/lambda_function.py

• Triggered by EventBridge rule every 60 seconds
• Fetches all is_active = true services from RDS
• Pings each URL with a 10s timeout
• Sends {service_id, user_id, url, status, latency_ms} to SQS

processor/lambda_function.py

• Triggered by SQS queue
• Writes to Redis: status:{service_id} → {status, response_time, checked_at} (TTL 90s)
• Inserts historical row into service_status table in RDS

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Tech Stack

Layer	Technology
Runtime	Python 3.11
HTTP	urllib.request (stdlib, no extra deps)
Database	pg8000 (pure-Python PostgreSQL driver)
Cache	redis-py
Queue	AWS SQS
Scheduler	AWS EventBridge
Packaging	Docker (Linux-compatible deps) + zip

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Environment Variables

DATABASE_URL     ---
REDIS_URL        ---
SQS_QUEUE_URL     ---

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Deployment

Dependencies are built inside a Docker container to ensure Linux-compatible binaries, then zipped and uploaded to Lambda:

# Build processor package
docker run --rm -v "$PWD":/out python:3.11-slim bash -c \
  "pip install redis pg8000 -t /out/package-processor"

cd package-processor
zip -r ../processor.zip .
cd ../processor && zip -g ../processor.zip lambda_function.py

aws lambda update-function-code \
  --function-name statusnest-dev-processor \
  --zip-file fileb://processor.zip

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Project Structure

statusnest-worker/
├── monitor/
│   └── lambda_function.py    # Health check + SQS sender
├── processor/
│   └── lambda_function.py    # SQS consumer + Redis/RDS writer
├── terraform/                # Lambda + EventBridge + SQS Terraform (reference)
└── requirements.txt

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Related Repos

Repo	Description
statusnest-api	FastAPI microservices (auth, monitor, status)
statusnest-frontend	React SPA
statusnest-infra	Terraform IaC for all AWS infrastructure