How to Mock the Ambassador Pattern Retry Client in Python

import time
import random


class RetryingClient:
    """Retry wrapper simulating a flaky ambassador-style API client."""

    def __init__(self, max_attempts=3, base_delay=0.1):
        self.max_attempts = max_attempts
        self.base_delay = base_delay
        self.attempts = 0

    def _flaky_request(self):
        """Simulate a request that fails ~50% of the time."""
        self.attempts += 1
        if random.random() < 0.5:
            raise ConnectionError("Temporary network failure")
        return {"status": "ok", "attempt": self.attempts}

    def call(self):
        """Retry the flaky request with exponential backoff."""
        last_error = None
        for attempt in range(self.max_attempts):
            try:
                return self._flaky_request()
            except ConnectionError as exc:
                last_error = exc
                time.sleep(self.base_delay * (2 ** attempt))
        raise last_error


if __name__ == "__main__":
    client = RetryingClient(max_attempts=4)
    try:
        result = client.call()
        print(f"Success on attempt {result['attempt']}: {result}")
    except ConnectionError:
        print(f"Failed after {client.attempts} attempts")