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1 match

Calculate Error Rate from Log Stream in Python

Parses a mock log stream to count errors and compute the error percentage using a rolling window of recent entries.

import re
from collections import deque

def error_rate_from_log_stream(message):
    log_pattern = r'^\[(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2})\] (ERROR|INFO|DEBUG): (.*)$'
    recent_entries = deque(maxlen=100)
    error_count = 0
    total_count = 0

    for line in message.strip().split('\n'):
        match = re.mat…

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