epub-compare

A CLI tool to compare two EPUB files compression methods and structure.

Features

• Compression Method Comparison: Compare compression methods (STORED vs DEFLATED) for each file entry
• Structure Analysis: Analyze file structure and entry order differences
• EPUB Compliance Check: Verify that mimetype file is first and uncompressed (EPUB specification requirement)
• Detailed Reporting: Color-coded output showing differences between files
• Entry-by-Entry Comparison: Compare all entries in both files with clear status indicators

Installation

Global Installation

npm install -g epub-compare

Local Installation

npm install epub-compare

From Source

git clone https://github.com/kyungw00k/epub-compare.git
cd epub-compare
npm install

Usage

Global Installation

epub-compare <file1.epub> <file2.epub>

Local Installation

npx epub-compare <file1.epub> <file2.epub>

From Source

node index.js <file1.epub> <file2.epub>

Output Example

File 1: book1.epub
File 2: book2.epub

Entry Comparison:
────────────────────────────────────────────────────────────────────────────────────────────────────
Order Name                                   File1 Compression File2 Compression Status
────────────────────────────────────────────────────────────────────────────────────────────────────
0     mimetype                               STORED           STORED           Match
1     META-INF/container.xml                 DEFLATED         DEFLATED         Match
2     OEBPS/content.opf                      DEFLATED         DEFLATED         Match
3     OEBPS/toc.ncx                          DEFLATED         DEFLATED         Match
4     OEBPS/chapter1.xhtml                   DEFLATED         STORED           Different compression
5     OEBPS/chapter2.xhtml                   DEFLATED         DEFLATED         Match
6     OEBPS/extra-file.xhtml                 MISSING          DEFLATED         Only in file2

Summary:
──────────────────────────────────────────────────
Total entries in file1: 6
Total entries in file2: 7
File1: mimetype is first and uncompressed
File2: mimetype is first and uncompressed

Status Indicators

• 🟢 Match: Files are identical in compression method and order
• 🟡 Different compression: Same file but different compression method
• 🟡 Different order: Same file but different position in archive
• 🔴 Only in file1: File exists only in the first EPUB
• 🔴 Only in file2: File exists only in the second EPUB

Requirements

• Node.js >= 14.0.0

Dependencies

• adm-zip: ZIP file handling
• chalk: Terminal colors
• commander: CLI framework

Use Cases

• EPUB Optimization: Compare different compression settings
• Quality Assurance: Verify EPUB file structure compliance
• Debugging: Identify differences between EPUB versions
• Analysis: Understand compression patterns in EPUB files

License

MIT

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Issues

If you find any issues or have suggestions, please report them on GitHub Issues.

Author

Kyungwook Park - @kyungw00k