MBTA Subway Alert Monitor

How it works

This Coreflux LoT Notebook polls the MBTA v3 API every 2 minutes, reads active subway and light-rail alerts, and publishes them into stable topics. It turns the raw JSON:API response into three fixed alert slots, a live alert count, and an events/alert_change topic when the count changes.

Key features

• REST_API route: Fetches MBTA alerts from https://api-v3.mbta.com/alerts?filter[route_type]=0,1.
• Self-starting clock: Bootstraps polling with feed/enabled and a 2-minute action.
• JSON validation: Confirms the MBTA response shape before parsing.
• Fixed alert slots: Fan-out to alerts/1..3 keeps topic structure stable.
• Edge detection: Publishes events/alert_change only when the active count moves.
• Collapsed report model: Emits a compact SubwayReport summary to reports/network.

Prerequisites

• Internet egress from Coreflux
• No MBTA API key required at this cadence

Setup

1. Deploy the route, actions, and model.
2. Ensure demo/subway/feed/enabled is 1 to poll.
3. Read demo/subway/reports/network for the latest summary.

What this template does