📊 Metering API This is a lightweight metering API that logs and queries API usage per account. It supports individual usage event recording, time range querying, and rate limiting.

🚀 Hosted Version (Google Cloud Run) A live version is available at:

🔗 https://measure-229201178350.europe-north1.run.app

🧑‍💻 Running Locally ✅ Requirements Python 3.8+

PostgreSQL (or use SQLite for local testing)

pip or venv for managing Python dependencies

📦 Install Dependencies bash Copy Edit pip install -r requirements.txt ⚙️ Set Environment Variables Before running locally, export the following:

bash Copy Edit export FLASK_APP=main.py You may also want to export the database connection string (optional, if not hardcoded):

bash Copy Edit the config.py

export DATABASE_URL=postgresql://youruser:yourpassword@localhost:5432/measure

▶️ Start the App by running

flask run

By default, it will be served at http://127.0.0.1:5000

📡 API Endpoints POST /log-event Record a usage event.

Curl command with Request Body (JSON):

curl -X POST http://127.0.0.1:5000/log-event \
  -H "Content-Type: application/json" \
  -d '{
    "account_id": "acct_123",
    "endpoint": "/api/v1/some-feature",
    "timestamp": "2025-04-09T16:00:00Z"
  }'

{"message":"Event logged"}

Rate Limit: 50 requests per second per account_id

GET /usage Query usage data.

Query Params:

account_id (optional)

endpoint (optional)

start (required) – ISO 8601 format

end (required) – ISO 8601 format

Example:

GET /usage?account_id=acct_123&start=2025-04-01T00:00:00Z&end=2025-04-09T23:59:59Z

Rate Limit: 50 requests per second per account_id

Let me know if you’d like a section for testing (pytest), Dockerization, or deployment instructions.

Following are the major TODO to complete this project.

1. Move the secrets to a secret store and read from there.
2. Add monitoring and alerting to the api
3. If required add authentication to call the API.
4. Nango integration during Rate limit exceeded event