(Node.js) Generating Repeatable Random Data for Testing/Debugging

Demonstrates how to use the Fortuna PRNG to generate random-looking but repeatable non-random data for the purpose of testing and debugging.

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() {

    // All Chilkat classes can be unlocked at once at the beginning of a program
    // by calling UnlockBundle.  It requires a Bundle unlock code.
    var chilkatGlob = new chilkat.Global();
    var success = chilkatGlob.UnlockBundle("Anything for 30-day trial.");
    if (success !== true) {
        console.log(chilkatGlob.LastErrorText);
        return;
    }

    var fortuna = new chilkat.Prng();

    // Normally an application would seed the PRNG with entropy from
    // some real random source.  However, sometimes we want the same
    // random sequence of bytes for testing and debugging purposes.
    // This a reason why GetEntropy and AddEntropy are two different methods.
    // An application could omit the call to GetEntropy, and instead pass
    // non-random data to AddEntropy. For example:

    // Seed the PRNG with non-entropy, so we get a repeatable sequence.
    // Note: AddEntropy can be called any number of times.
    success = fortuna.AddEntropy("01020304","hex");
    success = fortuna.AddEntropy("hello world","ascii");

    // Generate some random data:
    var strRandHex = fortuna.GenRandom(16,"hex");
    var strRandBase64 = fortuna.GenRandom(22,"base64");
    var strRandBase58 = fortuna.GenRandom(32,"base58");

    console.log("hex random bytes: " + strRandHex);
    console.log("base64 random bytes: " + strRandBase64);
    console.log("base58 random bytes: " + strRandBase58);

    // Try it again with a different object to verify that the same results are obtained:
    var fortuna2 = new chilkat.Prng();

    success = fortuna2.AddEntropy("01020304","hex");
    success = fortuna2.AddEntropy("hello world","ascii");

    strRandHex = fortuna2.GenRandom(16,"hex");
    strRandBase64 = fortuna2.GenRandom(22,"base64");
    strRandBase58 = fortuna2.GenRandom(32,"base58");

    console.log("hex random bytes: " + strRandHex);
    console.log("base64 random bytes: " + strRandBase64);
    console.log("base58 random bytes: " + strRandBase58);

}

chilkatExample();