Logging and log analysis in Drone Programming - Mini Project: Build & Apply

Logging and Log Analysis with Drone Programming

📖 Scenario: You are working on a drone control system. To keep track of the drone's activities and detect problems, you need to create logs that record important events and then analyze these logs to find any errors.

🎯 Goal: Build a simple logging system that records drone events with their severity levels, then filter and display only the error logs for quick analysis.

📋 What You'll Learn

Create a list of log entries with exact event messages and severity levels

Add a variable to specify the severity level to filter logs

Use a loop or comprehension to select logs matching the filter severity

Print the filtered error logs exactly as specified

💡 Why This Matters

🌍 Real World

Logging is essential in drone systems to monitor flight status and detect issues early. Filtering logs helps engineers focus on critical problems quickly.

💼 Career

DevOps and site reliability engineers use logging and log analysis daily to maintain system health and troubleshoot errors efficiently.

1

Create the initial log entries list

Create a list called logs with these exact entries as dictionaries: {'event': 'Takeoff initiated', 'level': 'INFO'}, {'event': 'Altitude reached 100m', 'level': 'INFO'}, {'event': 'Battery low', 'level': 'WARNING'}, {'event': 'Motor failure detected', 'level': 'ERROR'}, {'event': 'Landing completed', 'level': 'INFO'}

Drone Programming

# Create the list of logs with exact entries
# Your code here

Hint

Use a list of dictionaries. Each dictionary must have keys 'event' and 'level' with exact string values.

2

Add a filter level variable

Create a variable called filter_level and set it to the string 'ERROR' to specify which log level to filter.

Drone Programming

logs = [
    {'event': 'Takeoff initiated', 'level': 'INFO'},
    {'event': 'Altitude reached 100m', 'level': 'INFO'},
    {'event': 'Battery low', 'level': 'WARNING'},
    {'event': 'Motor failure detected', 'level': 'ERROR'},
    {'event': 'Landing completed', 'level': 'INFO'}
]
# Create filter_level variable and set it to 'ERROR'
# Your code here

Hint

Just assign the string 'ERROR' to the variable filter_level.

3

Filter logs by severity level

Create a list called error_logs that contains only the entries from logs where the 'level' matches the filter_level. Use a list comprehension.

Drone Programming

logs = [
    {'event': 'Takeoff initiated', 'level': 'INFO'},
    {'event': 'Altitude reached 100m', 'level': 'INFO'},
    {'event': 'Battery low', 'level': 'WARNING'},
    {'event': 'Motor failure detected', 'level': 'ERROR'},
    {'event': 'Landing completed', 'level': 'INFO'}
]
filter_level = 'ERROR'
# Create error_logs list with entries where level equals filter_level
# Your code here

Hint

Use a list comprehension to select logs where log['level'] == filter_level.

4

Print the filtered error logs

Use a for loop to print each dictionary in error_logs exactly as it appears.

Drone Programming

logs = [
    {'event': 'Takeoff initiated', 'level': 'INFO'},
    {'event': 'Altitude reached 100m', 'level': 'INFO'},
    {'event': 'Battery low', 'level': 'WARNING'},
    {'event': 'Motor failure detected', 'level': 'ERROR'},
    {'event': 'Landing completed', 'level': 'INFO'}
]
filter_level = 'ERROR'
error_logs = [log for log in logs if log['level'] == filter_level]
# Print each log in error_logs
# Your code here

Hint

Use a for loop to print each dictionary in error_logs.

Practice

1. What is the main purpose of logging in drone programming?

easy

A. To reduce the drone's battery usage

B. To speed up the drone's flight

C. To change the drone's hardware settings

D. To record what the drone program does step by step

Solution

1. Step 1: Understand logging basics

   Logging means saving messages about what the program is doing.

2. Step 2: Identify the main goal of logging

   It helps track the program's actions step by step for review or debugging.

3. Final Answer:

   To record what the drone program does step by step -> Option D

4. Quick Check:

   Logging = record steps [OK]

Hint: Logging means writing down program actions stepwise [OK]

Common Mistakes:

• Confusing logging with hardware control
• Thinking logging speeds up the drone
• Assuming logging saves battery

2. Which of the following is the correct syntax to log an info message in a drone program using Python's logging module?

easy

A. log.info("Drone started flying")

B. logging.info("Drone started flying")

C. logging.loginfo("Drone started flying")

D. logging.info: "Drone started flying"

Solution

1. Step 1: Recall Python logging syntax

   The correct method to log info level messages is logging.info(message).

2. Step 2: Check each option

   logging.info("Drone started flying") matches the correct syntax exactly; others have wrong method names or punctuation.

3. Final Answer:

   logging.info("Drone started flying") -> Option B

4. Quick Check:

   logging.info() is correct method [OK]

Hint: Use logging.info("message") to log info level [OK]

Common Mistakes:

• Using wrong method names like log.info or logging.loginfo
• Using colon instead of parentheses
• Missing parentheses around the message

3. Given this Python code snippet for logging in a drone program:

import logging
logging.basicConfig(level=logging.WARNING)
logging.debug("Debug message")
logging.warning("Warning message")
logging.error("Error message")

What will be printed to the console?

medium

A. Warning message\nError message

B. Debug message\nWarning message\nError message

C. Error message only

D. No output

Solution

1. Step 1: Understand logging level setting

   basicConfig sets level to WARNING, so messages with level WARNING and above show.

2. Step 2: Check each log call

   debug is below WARNING, so not shown; warning and error are shown.

3. Final Answer:

   Warning message\nError message -> Option A

4. Quick Check:

   Level WARNING shows warning and error [OK]

Hint: Logs show messages at or above set level [OK]

Common Mistakes:

• Expecting debug messages to appear
• Thinking only error shows at WARNING level
• Confusing logging levels order

4. You see this error in your drone program logs:
AttributeError: 'Logger' object has no attribute 'loginfo'
What is the most likely cause?

medium

A. Setting logging level too high

B. Not importing the logging module

C. Using a wrong logging method name like loginfo instead of info

D. Logging message is empty

Solution

1. Step 1: Analyze the error message

   AttributeError means the Logger object does not have the called method.

2. Step 2: Identify the method name mistake

   loginfo is not a valid method; correct is info.

3. Final Answer:

   Using a wrong logging method name like loginfo instead of info -> Option C

4. Quick Check:

   Method name must be correct [OK]

Hint: Check method names carefully for typos [OK]

Common Mistakes:

• Assuming import error causes AttributeError
• Thinking logging level causes method errors
• Ignoring method name spelling

5. You want to analyze drone logs to find all error messages that happened between 2pm and 3pm. Which approach is best?

hard

A. Filter logs by timestamp and error level using a log analysis tool

B. Manually read the entire log file line by line

C. Change the drone code to print only errors during that hour

D. Delete all logs except those from 2pm to 3pm

Solution

1. Step 1: Understand log analysis goal

   You want to find error messages in a specific time range efficiently.

2. Step 2: Choose best method

   Using a log analysis tool to filter by timestamp and error level is efficient and accurate.

3. Final Answer:

   Filter logs by timestamp and error level using a log analysis tool -> Option A

4. Quick Check:

   Use tools to filter logs by time and level [OK]

Hint: Use tools to filter logs by time and error level [OK]

Common Mistakes:

• Trying to read logs manually which is slow
• Changing code instead of analyzing existing logs
• Deleting logs risks losing data