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Node.js Requires Chilkat v11.7.0+

Password-Protect a PDF with AES-256 Encryption

See more PDF Protection Examples

Demonstrates the simplest way to encrypt a PDF so that it needs a password to open. The passwords come from the UserPassword and OwnerPassword properties, and Protection with the encrypt operation and an empty JSON uses the defaults: AES-256, everything encrypted, every permission granted. Protection only records the security the PDF will be saved with. Nothing is encrypted until WriteFile is called.

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Node.js
NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

    //  This example requires the Chilkat API to have been previously unlocked.
    //  See Global Unlock Sample for sample code.

    //  The PDF used in this example is available at two_page_memo.pdf

    var pdf = new chilkat.Pdf();
    success = pdf.LoadFile("qa_data/pdf/two_page_memo.pdf");
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    //  The passwords are taken from these two properties at the time Protection is called.
    //  The user password opens the PDF.  The owner password opens it too, and is the one needed
    //  later to change or remove the protection.
    pdf.UserPassword = "user-secret";
    pdf.OwnerPassword = "owner-secret";

    //  An empty JSON asks for the defaults: AES-256, everything encrypted, every permission granted.
    var json = new chilkat.JsonObject();
    var jsonOut = new chilkat.JsonObject();
    success = pdf.Protection("encrypt",json,jsonOut);
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    //  Nothing has been encrypted yet.  "pending" describes the security the PDF will be saved with.
    console.log("algorithm: " + jsonOut.StringOf("pending.algorithm"));
    console.log("PDF version: " + jsonOut.StringOf("pending.pdfVersion"));
    console.log("password needed to open: " + jsonOut.BoolOf("pending.userPasswordRequired"));

    //  Writing the file applies it.
    success = pdf.WriteFile("qa_output/memo_encrypted.pdf");
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    //  PreLoadCheck reports a file's encryption without loading it, and needs no password.
    var checker = new chilkat.Pdf();
    var info = new chilkat.JsonObject();
    success = checker.PreLoadCheck("qa_output/memo_encrypted.pdf",info);
    if (success == false) {
        console.log(checker.LastErrorText);
        return;
    }

    console.log("encrypted: " + info.BoolOf("encrypted"));
    console.log("openPasswordRequired: " + info.BoolOf("openPasswordRequired"));

    //  With the password, the PDF opens normally.
    var reader = new chilkat.Pdf();
    reader.UserPassword = "user-secret";
    success = reader.LoadFile("qa_output/memo_encrypted.pdf");
    if (success == false) {
        console.log(reader.LastErrorText);
        return;
    }

    console.log("pages: " + reader.NumPages);

    //  Sample output:

    //  algorithm: aes-256
    //  PDF version: 1.7
    //  password needed to open: True
    //  encrypted: True
    //  openPasswordRequired: True
    //  pages: 2

}

chilkatExample();