(JavaScript) 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.
var success = false;
// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
success = false;
var fortuna = new CkPrng();
// 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 CkPrng();
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);
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