Project 11 — Diary App

Write encrypted daily journal entries, search past entries by keyword or date, and export to Markdown.

file I/Oencryptiondiarysearchmarkdown

Duration

⏱ 2.5 hours

Level

📊 Intermediate-Advanced Applied

Prerequisite

🎯 Intermediate Week 6

OUTCOME

An encrypted diary app with keyword search and Markdown export

What you'll learn

1Store entries as individual .txt files with date filenames
2Encrypt entries with a simple XOR cipher (or Fernet from cryptography)
3Search all entries for a keyword
4Export selected entries to a single Markdown file

Entry Format

text

# 2024-05-15
Mood: 😊
Weather: Sunny

Today I started a new Python project. The weather was great,
and I managed to finish the basic structure in a few hours...

Commands

write [date] — open editor for today's entry (or specified date)
read [date] — display entry for a date
search <keyword> — find all entries containing keyword
export [from] [to] — export date range to diary.md
stats — word count, mood distribution, writing streak

📝 Exercises

Try them yourself first, then open the solution to compare.

Exercise 1

Build the diary app

Goal: Implement write, read, search, and export with optional encryption.

Requirements

Date-based file naming
read/write commands
Keyword search across all entries
Markdown export

Example code / lecture materials

All lecture materials and example code are openly available on GitHub.

View on GitHub ↗