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timmaniktimmanik
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Added a module on refactoring with IT use cases
1 parent 35be43a commit cf217c4

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+532
-558
lines changed

‎.gitignore

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gh-cp-venv/
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8-
99-archive/
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99-archive/
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*__pycache__/

‎04-refactoring/IT/mock_ping.py

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from typing import Union, Optional
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from dataclasses import dataclass
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from enum import Enum
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import time
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class ServerStatus(Enum):
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UP = "UP"
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DOWN = "DOWN"
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TIMEOUT = "TIMEOUT"
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DNS_ERROR = "DNS_ERROR"
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UNAUTHORIZED = "UNAUTHORIZED"
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@dataclass
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class PingResult:
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status: ServerStatus
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response_time: float
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error_message: Optional[str] = None
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def __bool__(self):
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return self.status == ServerStatus.UP
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class MockPingError(Exception):
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"""Base exception for mock ping errors"""
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pass
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class MockDNSError(MockPingError):
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"""Raised when DNS resolution fails"""
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pass
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class MockTimeoutError(MockPingError):
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"""Raised when ping times out"""
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pass
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class MockAuthenticationError(MockPingError):
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"""Raised when authentication is required but not provided"""
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pass
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def mock_ping(server: str, timeout: float = 1.0, require_auth: bool = False) -> PingResult:
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"""
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Simulates pinging a server with various realistic scenarios
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Args:
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server: Server address to ping
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timeout: Maximum time to wait for response
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require_auth: Whether authentication is required
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Returns:
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PingResult object containing status and response information
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Raises:
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MockDNSError: If DNS resolution fails
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MockTimeoutError: If ping times out
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MockAuthenticationError: If authentication is required but not provided
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ValueError: If server parameter is invalid
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"""
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if not isinstance(server, str):
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raise ValueError(f"Server must be a string, got {type(server).__name__}")
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if not server:
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raise ValueError("Server address cannot be empty")
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if server.startswith("timeout"):
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time.sleep(timeout + 0.1)
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raise MockTimeoutError(f"Connection to {server} timed out after {timeout} seconds")
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if server.startswith("auth") and not require_auth:
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raise MockAuthenticationError(f"Authentication required for {server}")
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if ".invalid" in server:
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raise MockDNSError(f"Could not resolve hostname: {server}")
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mock_responses = {
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"192.168.1.1": PingResult(ServerStatus.UP, 0.001),
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"example.com": PingResult(ServerStatus.DOWN, 0.0, "Connection refused"),
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"localhost": PingResult(ServerStatus.UP, 0.0001),
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"slow.server": PingResult(ServerStatus.UP, 0.8),
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"firewall.blocked": PingResult(ServerStatus.DOWN, 0.001, "Connection blocked by firewall")
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}
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response_time = timeout * 0.1
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return mock_responses.get(
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server,
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PingResult(ServerStatus.DOWN, response_time, f"Unknown host: {server}")
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)

‎04-refactoring/IT/server_availability.py

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import datetime
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from mock_ping import mock_ping
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from io import StringIO
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def check_server_availability(servers):
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output = StringIO()
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# Write header with timestamp
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output.write(f"Time: {datetime.datetime.now()}\n")
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# Check each server
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for server in servers:
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try:
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result = mock_ping(server)
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status = "UP" if result else "DOWN"
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output.write(f"{server} is {status}\n")
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except:
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output.write(f"Error checking server {server}\n")
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# Print and return the complete output
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result = output.getvalue()
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print(result)
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return

‎04-refactoring/IT/server_availability_hints.py

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import datetime
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from mock_ping import mock_ping
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from io import StringIO
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def check_server_availability(servers):
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# No input validation or type hints
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try:
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output = StringIO()
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# Write header with timestamp
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output.write(f"Time: {datetime.datetime.now()}\n")
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for s in servers: # Poor variable naming
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try:
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# Ignores all the rich information from mock_ping
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# and reduces it to just True/False
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result = mock_ping(s)
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if result == True: # Non-pythonic comparison
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f.write(s + " is up\n")
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else:
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# Ambiguous error messaging
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f.write(s + " is down\n")
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except: # Bare except clause
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# Generic error message without context
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f.write("Error checking server\n")
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f.close() # Manual file closing
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except: # Another bare except
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# Unhelpful error message
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print("Error writing to log file") # Inconsistent error reporting (print vs write)
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return # Silent return on error

‎04-refactoring/IT/server_availability_refactored.py

Whitespace-only changes.

‎04-refactoring/IT/test-for-messy code-notebook.ipynb

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{
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"cells": [
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"# Server Availability Testing Scenarios\n",
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"\n",
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"This notebook contains various test scenarios for the server availability script. Each scenario tests different aspects of error handling and edge cases. After refactoring the code, you can rerun these cells to see how the error handling has improved."
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]
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},
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{
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"cell_type": "code",
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"execution_count": 12,
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"metadata": {},
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"outputs": [],
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"source": [
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"from server_availability import check_server_availability"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"## Scenario 1: Basic Server Checks\n",
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"Testing basic server availability checks with known servers."
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"basic_servers = [\n",
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" \"192.168.1.1\", # Should be up\n",
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" \"example.com\", # Should be down\n",
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" \"localhost\" # Should be up\n",
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"]\n",
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"\n",
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"check_server_availability(basic_servers)"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"## Scenario 2: Network Issues\n",
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"Testing how the script handles various network-related issues."
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"network_test_servers = [\n",
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" \"timeout.example.com\", # Should timeout\n",
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" \"auth.internal.network\", # Requires authentication\n",
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" \"nonexistent.invalid\", # DNS resolution failure\n",
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" \"firewall.blocked\", # Blocked by firewall\n",
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" \"timeout.server\" # High latency\n",
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"]\n",
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"\n",
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"check_server_availability(network_test_servers)"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"## Scenario 3: Input Validation\n",
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"Testing how the script handles invalid inputs."
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"edge_case_servers = [\n",
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" \"\", # Empty string\n",
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" 123, # Wrong type\n",
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" \"localhost\", # Valid server\n",
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" \"서버.example.com\", # Unicode\n",
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" None, # None value\n",
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" \" \" # Whitespace only\n",
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"]\n",
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"\n",
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"check_server_availability(edge_case_servers)"
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]
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},
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{
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"cell_type": "markdown",
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"metadata": {},
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"source": [
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"## Scenario 4: Multiple Failures\n",
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"Testing how the script handles multiple failing cases in sequence."
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]
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},
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{
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"cell_type": "code",
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"execution_count": null,
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"metadata": {},
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"outputs": [],
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"source": [
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"recovery_test_servers = [\n",
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" \"192.168.1.1\", # Should succeed\n",
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" None, # Should fail\n",
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" \"localhost\", # Should succeed\n",
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" \"timeout.example.com\", # Should timeout\n",
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" \"example.com\", # Should fail\n",
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" \"slow.server\" # Should succeed but slow\n",
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"]\n",
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"\n",
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"check_server_availability(recovery_test_servers)"
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]
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}
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],
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"metadata": {
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"kernelspec": {
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"display_name": "gh-cp-venv",
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"language": "python",
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"name": "python3"
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},
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"language_info": {
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"codemirror_mode": {
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"name": "ipython",
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"version": 3
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},
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"file_extension": ".py",
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"mimetype": "text/x-python",
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"name": "python",
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"nbconvert_exporter": "python",
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"pygments_lexer": "ipython3",
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"version": "3.12.3"
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}
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},
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"nbformat": 4,
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"nbformat_minor": 4
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}

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