(Node.js) Unzip Files Matching a Pattern (such as *.xml)

Example code to unzip Files Matching a Pattern (such as *.xml)

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 works with the .zip located at http://www.example-code.com/data/test.zip

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

    // First, let's download the .zip
    var http = new chilkat.Http();
    var success = http.Download("http://www.example-code.com/data/test.zip","qa_test/test.zip");
    if (success !== true) {
        console.log(http.LastErrorText);
        return;
    }

    var zip = new chilkat.Zip();

    success = zip.OpenZip("qa_test/test.zip");
    if (success !== true) {
        console.log(zip.LastErrorText);
        return;
    }

    // Show what's in the .zip by getting the directory as XML.
    var zipContentsXml = zip.GetDirectoryAsXML();
    if (zip.LastMethodSuccess !== true) {
        console.log(zip.LastErrorText);
        return;
    }

    console.log(zipContentsXml);

    // In this case, the contents of our .zip look like this:
    // <?xml version="1.0" encoding="utf-8" ?>
    // <zip_contents>
    //     <dir name="test">
    //         <dir name="abc">
    //             <dir name="123">
    //                 <file>ecc_public.pem</file>
    //                 <file>starfish.jpg</file>
    //             </dir>
    //             <file>comodo-certificates.pem</file>
    //             <file>pigs.xml</file>
    //         </dir>
    //         <file>COMODORSACertificationAuthority.crt</file>
    //         <file>hamlet.xml</file>
    //     </dir>
    // </zip_contents>

    // ------------------------------------------------------------------------
    // If we wish to unzip only .xml files, use "*.xml" for the pattern\
    // Unzip to the "qa_output" directory relative to our current working directory.
    // (You may unzip to an absolute path by passing an absolute path, such as "/someDir" or
    // "C:/someDir", etc.)
    // This will unzip only the .xml files.  The relative directory structure within
    // the .zip will be created in the local filesystem under the unzip directory
    // path passed in the first argument, which in this case is "qa_output".
    var count = zip.UnzipMatching("qa_output","*.xml",true);
    if (count < 0) {
        console.log(zip.LastErrorText);
        return;
    }

    console.log("unzipped " + count + " matching file(s).");

    // ------------------------------------------------------------------------
    // If we wish to unzip only files under the "123" directory, we can do this:
    count = zip.UnzipMatching("qa_output2","*/123/*",true);
    if (count < 0) {
        console.log(zip.LastErrorText);
        return;
    }

    console.log("unzipped " + count + " matching file(s).");

    // ------------------------------------------------------------------------
    // If no asterisk character is used, then the match must be exact.
    // For example, to unzip "test/hamlet.xml" we must pass the exact path
    // as it is in the .zip.  We cannot just pass "hamlet.xml".
    count = zip.UnzipMatching("qa_output3","test/hamlet.xml",true);
    if (count < 0) {
        console.log(zip.LastErrorText);
        return;
    }

    console.log("unzipped " + count + " matching file(s).");

    // ------------------------------------------------------------------------
    // If we want to unzip any file named "hamlet.xml" found in any sub-directory...
    count = zip.UnzipMatching("qa_output4","*/hamlet.xml",true);
    if (count < 0) {
        console.log(zip.LastErrorText);
        return;
    }

    console.log("unzipped " + count + " matching file(s).");

}

chilkatExample();