QR Code Label Generator for Paperless-ngx

A Go application for generating PDF sheets of QR code labels for Paperless-ngx ASN (Archive Serial Number) labels. Designed for Avery L4731REV-25 and compatible label sheets (see Label Sheet Specifications for a complete list), this tool helps you create physical labels for your document management system. It can be used both as a CLI application and as a HTTP server.

Features

• Generates QR codes for Paperless-ngx ASNs with customizable prefixes
• Perfect for creating physical labels for your paper documents before scanning
• Supports multiple label sheet formats including Avery L4731REV-25 and HERMA 10001 (189 labels per page, 7×27 grid)
• Can be run as a CLI tool or HTTP server
• Configurable number format with leading zeros
• Debug mode with visible label borders
• Temporary file cleanup
• PDF output with precise label positioning

Public Instance

A public instance is available at https://asn-qrcode-generator.tobiaswx.com for quick label generation without the need to set up your own server. This instance is hosted on a private server and tunneled via Cloudflare, so it should be available most of the time (barring power or internet outages).

Example usage:

https://asn-qrcode-generator.tobiaswx.com/generate?pages=25

This will generate 25 pages of labels, starting with ASN0001 up to ASN4725 (189 labels per page). The example uses the default values (prefix="ASN", start=1, zeros=4) for simplicity - all parameters can be customized as needed. PDF generation for that example typically takes 5-10 seconds.

For immediate access to the most commonly used configuration (25 pages with default settings), you can download a pre-generated PDF directly:

https://hel1.your-objectstorage.com/tobiaswx-github-public/asn-qrcode-generator/asn0001-asn4725_25pages_default.pdf

Note: While the public instance is provided as a convenience, for production use or if you need guaranteed availability, consider running your own instance using the instructions below.

Installation

go get github.com/tobiaswx/asn-qrcode-generator

Usage

CLI Mode

Basic usage with default settings:

go run main.go

Generate multiple pages with custom settings:

go run main.go -start 1000 -prefix "ASN" -pages 2 -zeros 5 -output "labels.pdf"

Available flags:

• -start: Starting number (default: 1)
• -prefix: Prefix for numbers (default: "ASN")
• -pages: Number of pages to generate (default: 1)
• -output: Output PDF filename (default: "labels.pdf")
• -borders: Show label borders for debugging (default: false)
• -zeros: Number of leading zeros in the number (default: 4)

Server Mode

Start the HTTP server:

go run main.go -serve -port 8080

Generate labels via HTTP request:

http://localhost:8080/generate?start=1000&prefix=ASN&pages=2&zeros=5&borders=true

Query parameters:

• start: Starting number
• prefix: Prefix for numbers
• pages: Number of pages
• zeros: Number of leading zeros
• borders: Show borders (true/false)

Label Sheet Specifications

The generator is configured for Avery L4731REV-25 label sheets with the following specifications:

• 189 labels per page (7×27 grid)
• Label dimensions: 25.4mm × 10.0mm
• Horizontal gutter: 2.55mm
• Left margin: 8.45mm
• Top margin: 13.5mm
• QR code size: 9.0mm

Compatible label sheets:

• Avery L4731REV-25 (primary supported format)
• HERMA 10001 (confirmed compatible due to identical dimensions)

Docker

The application is available as a Docker image from GitHub Container Registry:

docker pull ghcr.io/tobiaswx/asn-qrcode-generator:latest

Run the container:

docker run -p 8080:8080 ghcr.io/tobiaswx/asn-qrcode-generator:latest

Available platforms:

• linux/amd64
• linux/arm64

Dependencies

• github.com/boombuler/barcode
• github.com/go-pdf/fpdf

Building from Source

git clone https://github.com/tobiaswx/asn-qrcode-generator
cd asn-qrcode-generator
go build

Contributing

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

License

MIT License