Retrieving attached files

This guide will show you how to retrieve list of file attachments and extract it from the PDF file.

Before you begin #

You should get your API key from yourUniCloud account.

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

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 render folder in the unipdf-examples directory.

cd unipdf-examples/attachment

How it works #

Lines 7-14 import the UniPDF packages and other required dependencies.

The init function in lines 16-23 authenticates your request with your UNIDOC_LICENSE_API_KEY.

The main function in lines 25-35 defines which PDF file be used as an input file and passes it to the listAttachments function in line 37-73 that will retrive the attachment list and store it locally.

First we’ll need to open the PDF file and get the PDFReader object (line 38-48) then from there we could call the GetAttachedFiles function to get the list of file attachments.

The EmbeddedFile method returned from the GetAttachedFiles function has a Content attribute that could be written to a file (line 54-67).

Run the code #

Run this command to extract the attached files from a PDF document and save it under an output folder. This will also get all the required dependencies to run the program.

go run pdf_get_attachment.go