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Add Password Protection to PDF using Node.js REST API

Node.js PDF developers can easily add password protection to their documents by leveraging the Aspose.PDF Cloud REST API. This guide walks you through the entire process—from setting up your environment and configuring passwords to applying encryption and downloading the protected file—using the official Aspose.PDF Cloud SDK for Node.js. For more information about the PDF format, see the PDF file info page.

Prerequisite

Steps to Password Protect PDF Doc using Node.js REST Interface

  1. Import the required modules for Aspose PDF Cloud, file handling, and text encoding.
  2. Create a new PdfApi instance with your API key and App SID to authorize access to Aspose’s cloud services.
  3. Open the target PDF file from disk so it can be read and processed.
  4. Convert the user and owner passwords into Base64 strings for secure transmission.
  5. Build a list of permissions (e.g., printing, extracting, modifying) that the encrypted PDF will allow.
  6. Call PutEncryptDocument to apply encryption, specifying the output file name, encryption type, and the permissions list.
  7. After encryption, download the newly encrypted file from Aspose Cloud.
  8. Write the downloaded, encrypted content to a new file on your computer.

These steps summarize how to protect a PDF document using the Node.js‑based API: import the necessary classes, instantiate PdfApi, open the PDF, set user/owner passwords, define allowed permissions, invoke PutEncryptDocument, then download and save the protected file. Print the response status to confirm success.

Code to Password Protect PDF Document using Node.js RESTful Service

The snippet above demonstrates how to add a password to a PDF using the Node.js Low Code API. Remember to convert passwords to Base64 strings; otherwise, an exception will be thrown. You can also extend the permissions list with options such as ModifyTextAnnotations, FillForm, ExtractContentWithDisabilities, AssembleDocument, and PrintingQuality.

For related tasks, see the article on Verify signature in PDF using Node.js REST API.