Data rotation and cleanup in Raspberry Pi - Mini Project: Build & Apply

Data rotation and cleanup

📖 Scenario: You are managing a Raspberry Pi that collects sensor data every day. To save space, you want to keep only the latest 5 days of data files and remove older ones automatically.

🎯 Goal: Build a Python script that lists data files, keeps only the latest 5 files, and deletes older files to clean up storage.

📋 What You'll Learn

Create a list of data file names with dates in the format 'data_YYYYMMDD.txt'.

Set a variable to keep track of how many recent files to keep.

Use a sorting method to find the latest files and select only those to keep.

Print the list of files that will be deleted.

💡 Why This Matters

🌍 Real World

This script helps Raspberry Pi users manage limited storage by automatically cleaning old sensor data files.

💼 Career

Understanding file management and cleanup scripts is useful for system administrators and IoT developers who maintain devices with limited storage.

1

Create the list of data files

Create a list called data_files with these exact file names: 'data_20230420.txt', 'data_20230421.txt', 'data_20230422.txt', 'data_20230423.txt', 'data_20230424.txt', 'data_20230425.txt', 'data_20230426.txt'.

Raspberry Pi

# Create the list of data files
# Your code here

Need a hint?

Use square brackets to create a list and put each file name as a string inside.

2

Set the number of files to keep

Create a variable called keep_count and set it to 5 to keep the latest 5 files.

Raspberry Pi

data_files = ['data_20230420.txt', 'data_20230421.txt', 'data_20230422.txt', 'data_20230423.txt', 'data_20230424.txt', 'data_20230425.txt', 'data_20230426.txt']
# Set the number of files to keep
# Your code here

Need a hint?

Just assign the number 5 to the variable keep_count.

3

Select files to delete

Sort the data_files list in ascending order and create a new list called files_to_delete that contains all files except the last keep_count files.

Raspberry Pi

data_files = ['data_20230420.txt', 'data_20230421.txt', 'data_20230422.txt', 'data_20230423.txt', 'data_20230424.txt', 'data_20230425.txt', 'data_20230426.txt']
keep_count = 5
# Sort data_files and select files to delete
# Your code here

Need a hint?

Use the sorted() function to sort the list. Use slicing to get all but the last keep_count files.

4

Print files to delete

Print the files_to_delete list to show which files will be deleted.

Raspberry Pi

data_files = ['data_20230420.txt', 'data_20230421.txt', 'data_20230422.txt', 'data_20230423.txt', 'data_20230424.txt', 'data_20230425.txt', 'data_20230426.txt']
keep_count = 5

sorted_files = sorted(data_files)
files_to_delete = sorted_files[:-keep_count]
# Print the files to delete
# Your code here

Need a hint?

Use print(files_to_delete) to show the list.