Instruction Downloader Script

This Python script is designed to download LEGO building instructions for a given set ID from the Rebrickable website. It will search for all available instruction links related to a set, and based on the presence of a "V29" (or "V 29") tag in the alt text, it will download specific versions of the instructions.

Features

• Download Specific Versions: Automatically handles downloading of instructions based on the V29 version.
• Handle Complex Alt Text: The script handles alt text that includes variations like V29, including x/y patterns and ignores invalid patterns.
• Fallback for Missing or Invalid V29 Versions: If no valid V29 instruction links are found, the script will download all available instructions.
• Customizable Download Filenames: Instructions are saved with filenames based on the set ID and the instruction variant.
• User-Agent Spoofing: The script mimics a browser request to avoid being blocked as a bot.

Requirements

• Python 3.x
• requests library
• beautifulsoup4 library

You can install the required dependencies by running:

python3 -m pip install requests beautifulsoup4

Usage

Running the Script

To use this script, you need to provide the LEGO set ID as an argument. The set ID is typically in the format ####-1 (e.g., 10313-1).

Example Command

python3 dl.py 10313-1

This will download the LEGO building instructions for the set 10313-1 (Wildflower Bouquet).

How It Works

1. The script will visit the Rebrickable page for the provided set ID.
2. It will search for all available instruction links containing "LEGO Building Instructions" in the alt text.
3. If links with "V29" are found, the script will download them in order, naming them as {set_id}+1.pdf, {set_id}+2.pdf, etc.
4. If the x/y values in the alt text are invalid (i.e., x or y greater than 10), those links will be ignored.
5. If no valid V29 links are found, the script will fall back to downloading all available instruction links, with filenames based on the alt text.

Script Output

The script will print status messages during the execution, including:

• URLs of the files being downloaded.
• The filenames that the instructions will be saved as.
• Any errors encountered while downloading.

Example Output

Downloading: https://rebrickable.com/instructions/10313-1/123456/download/?expire=1737409263 -> 10313+1.pdf
Saved: 10313+1.pdf
Downloading: https://rebrickable.com/instructions/10313-1/789012/download/?expire=1737409263 -> 10313+2.pdf
Saved: 10313+2.pdf

If no valid V29 links are found, the script will print out the available instruction links.

Error Handling

• If the page cannot be loaded (e.g., invalid set ID), the script will print an error message and stop.
• If an instruction download fails, the script will print an error message with the HTTP status code.

Customization

• User-Agent: The script uses a browser-like User-Agent string to avoid being detected as a bot. You can customize the headers variable if needed.
• Download Filename Format: The filenames for the downloaded instructions are automatically generated. You can modify the download_instructions function to change the naming convention.

License

This project is licensed under the MIT License - see the LICENSE file for details.