How to Check Service Readiness Dependencies in Python

import sys
from datetime import datetime


def check_dependencies(config):
    results = []
    for dep, required in config.items():
        available = mock_availability(dep)
        status = "READY" if available >= required else "NOT READY"
        results.append((dep, available, required, status))
    return results


def mock_availability(dep):
    slots = {"database": 5, "cache": 3, "queue": 2, "auth": 4}
    return slots.get(dep, 0)


if __name__ == "__main__":
    config = {
        "database": 3,
        "cache": 4,
        "queue": 1,
        "auth": 2,
        "unknown": 1,
    }
    print(f"Readiness check at {datetime.now():%Y-%m-%d %H:%M:%S}")
    for dep, available, required, status in check_dependencies(config):
        print(f"{dep:12s} available={available} required={required} -> {status}")
    if all(status == "READY" for _, _, _, status in check_dependencies(config)):
        print("Overall: ALL SYSTEMS READY")
    else:
        print("Overall: SOME DEPENDENCIES MISSING")
        sys.exit(1)