REST API Reference

All services expose FastAPI with automatic Swagger UI at /docs, Prometheus metrics at /metrics, and health checks at /health.

BankChurn Swagger	NLPInsight Swagger	ChicagoTaxi Swagger

Endpoints

BankChurn (:8001)

Method	Path	Description
GET	/health	Health check
POST	/predict	Churn prediction (add ?explain=true for SHAP contributions)
GET	/metrics	Prometheus metrics
GET	/docs	Swagger UI

Predict Request:

{"CreditScore":650,"Geography":"France","Gender":"Male","Age":40,"Tenure":5,"Balance":60000,"NumOfProducts":2,"HasCrCard":1,"IsActiveMember":1,"EstimatedSalary":50000}

Response:

{"prediction":0,"probability":0.15,"risk_level":"LOW"}

NLPInsight (:8003)

Method	Path	Description
GET	/health	Health check
POST	/predict	Sentiment analysis
GET	/metrics	Prometheus metrics
GET	/docs	Swagger UI

Predict Request:

{"text":"The company reported strong quarterly earnings growth"}

Response:

{"label":"positive","confidence":0.92,"scores":{"positive":0.92,"neutral":0.06,"negative":0.02}}

ChicagoTaxi (:8004)

Method	Path	Description
GET	/health	Health check
GET	/demand	Query demand predictions by area/hour
GET	/areas	List all areas ranked by demand
GET	/pipeline/status	ETL pipeline metadata
GET	/metrics	Prometheus metrics
GET	/docs	Swagger UI

Demand Request:

curl "http://localhost:8004/demand?area=8&hour=14&limit=5"

Response:

{"predictions":[{"pickup_community_area":8,"hour":14,"predicted_demand":42.3}],"total":1}

Live Predictions

BankChurn (with SHAP)	NLPInsight (Sentiment)	ChicagoTaxi (Demand)

SHAP Explanation	Prometheus Metrics

Common Patterns

• Health Check: All services return {"status":"healthy"} at /health
• Metrics: Prometheus format at /metrics — custom counters per service
• Validation: Pydantic schemas with automatic 422 error responses
• CORS: Enabled for all origins
• Structured Logging: JSON format in K8s, human-readable locally

---

Last Updated: March 2026 — v3.5.3