(Node.js) Append Files to Existing Zip w/out Rewriting Entire Zip

Demonstrates how to use the QuickAppend method to append files to an existing .zip archive. This method works by editing the existing .zip -- it does not rewrite or recompress the contents of the existing .zip. It is the fastest way to append additional files to a pre-existing large .zip archive. Note: The QuickAppend method is new and available in the pre-release downloads, or in official releases dated after 6-October-2007.

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOSX, and ARM

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

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

    var zip = new chilkat.Zip();

    // The NewZip method only initializes the Zip object -- it does
    // not create or write a .zip file.
    var success = zip.NewZip("notUsed.zip");
    if (success !== true) {
        console.log(zip.LastErrorText);
        return;
    }

    // Add a reference to a file.  This is the file that will
    // be added to a pre-existing .zip archive.  
    // Note: this does not read or compress the file contents --
    // it simply adds a reference to the zip object.
    var saveExtraPath = false;
    success = zip.AppendOneFileOrDir("something.dat",saveExtraPath);
    if (success !== true) {
        console.log(zip.LastErrorText);
        return;
    }

    // Appends the contents of the zip object to the preExisting.zip
    // zip archive.  preExisting.zip is opened, and the files
    // referenced by this zip object are streamed in, compressed,
    // and appended to the end of the archive.
    success = zip.QuickAppend("preExisting.zip");
    if (success !== true) {
        console.log(zip.LastErrorText);
        return;
    }

    console.log("Success!");

    // Note: Additional files, directory trees, or in-memory data
    // can be appended by calling AppendOneFileOrDir, AppendFiles,
    // AppendString, AppendData, etc. multiple times.
    // Whatever files and/or in-memory data that are referenced by
    // this zip object will be appended to preExisting.zip when
    // QuickAppend is called

}

chilkatExample();