Get Outlines

Bookmarks list the content per page in a PDF document for accessibilty. Each bookmark is associated with a specific page in the document, allowing users to navigate content in the PDF document.

This guide will show you how to retrieve outlines or bookmarks from a PDF document and save them to a JSON file. The resulting JSON file can be used with the set outlines guide to apply outlines to a PDF document.

Sample Input #

Before you begin #

You should get your API key from your UniCloud account.

If this is your first time using UniPDF SDK, follow this guide to set up a local development environment.

Project setup #

Clone the project repository #

In your terminal, clone the examples repository. It contains the Go code we will be using for this guide.

git clone https://github.com/unidoc/unipdf-examples.git

Navigate to the outlines folder in the unipdf-examples directory.

cd unipdf-examples/outlines

Configure environment variables #

Replace the UNIDOC_LICENSE_API_KEY with your API credentials from your UniDocaccount.

Linux/Mac #

export UNIDOC_LICENSE_API_KEY=PUT_YOUR_API_KEY_HERE

Windows #

set UNIDOC_LICENSE_API_KEY=PUT_YOUR_API_KEY_HERE

How it works #

Lines 11-18 import the UniPDF packages and other required dependencies.

The init function in lines 20-27 authenticate your request with your UNIDOC_LICENSE_API_KEY.

The main function in lines 29-44 validates your input and passes it as an arguement to the getOutlines function.

Lines 46-65 define the getOutlines function, which accepts inputPath as a parameter. The function reads the PDF from the inputPath with pdfReader and calls the GetOutlines method to return the PDF’s outlines.

Run the code #

Run this command to retrieve the input PDF’s outlines. This will also get all the required dependencies to run the program.

go run pdf_get_outlines.go input.pdf > outlines.json 

Sample output #

You will get the PDF’s outlines or bookmarks similar to this in a JSON file.

{
    "entries": [
        {
            "title": "Table of Contents",
            "dest": {
                "page": 1,
                "mode": "XYZ",
                "x": 0,
                "y": 792,
                "zoom": 0
            }
        },
        {
            "title": "1. Document control",
            "dest": {
                "page": 2,
                "mode": "XYZ",
                "x": 50,
                "y": 652,
                "zoom": 0
            },
            "entries": [
                {
                    "title": "1.1. Issuer details",
                    "dest": {
                        "page": 2,
                        "mode": "XYZ",
                        "x": 50,
                        "y": 634,
                        "zoom": 0
                    }
                }
            ]
        },
        {...}