composition.md

Composing Multiple Blockchains in Bonsai

Abacus provides the functionality to create individual Blockchain<T> instances for various cryptocurrencies. Additionally, Abacus enables the composition of these blockchains into a single, cohesive data stream. This document outlines the process of composing multiple blockchains and the subsequent handling of their data.

Composing Blockchains

By leveraging Reactive Extensions (Rx), Abacus can combine several observables into one, allowing for simultaneous observation and processing of multiple blockchain instances.

Example

Here's a simplified example showcasing how to compose multiple Blockchain<T> instances:

using Abacus.Observables.Blockchain;
using System;
using System.Linq;
using System.Reactive.Linq;

namespace Abacus
{
    public static class BlockchainComposer
    {
        public static void Main(string[] args)
        {
            // Compose multiple blockchain observables
            var composedChains = ComposeBlockchains(
                Configuration.BSV_MagicNumber,
                Configuration.BCH_MagicNumber,
                Configuration.BTC_MagicNumber
            );

            // Subscribe to the composed observable to process incoming blocks
            composedChains.Subscribe(composedBlock =>
            {
                // Handle the composed block data here
                Console.WriteLine($"Composed Block from {composedBlock.Item1.Symbol}: Height = {composedBlock.Item1.Height}, Hash = {composedBlock.Item1.Hash}");
                Console.WriteLine($"Composed Block from {composedBlock.Item2.Symbol}: Height = {composedBlock.Item2.Height}, Hash = {composedBlock.Item2.Hash}");
                Console.WriteLine($"Composed Block from {composedBlock.Item3.Symbol}: Height = {composedBlock.Item3.Height}, Hash = {composedBlock.Item3.Hash}");
            });

            Console.WriteLine("Observing composed blockchains. Press any key to exit.");
            Console.ReadKey();
        }

        private static IObservable<(IBlock<BSV>, IBlock<BCH>, IBlock<BTC>)> ComposeBlockchains(uint bsvMagicNumber, uint bchMagicNumber, uint btcMagicNumber)
        {
            // Assume BlockGenerator.Generate returns an IObservable<IBlock<T>> for the given magic number
            var bsvBlocks = BlockGenerator<Block<BSV>>.Generate(bsvMagicNumber, Configuration.DataDirPath);
            var bchBlocks = BlockGenerator<Block<BCH>>.Generate(bchMagicNumber, Configuration.DataDirPath);
            var btcBlocks = BlockGenerator<Block<BTC>>.Generate(btcMagicNumber, Configuration.DataDirPath);

            // Use Observable.Zip to combine multiple observables
            return Observable.Zip(bsvBlocks, bchBlocks, btcBlocks, (bsv, bch, btc) => (bsv, bch, btc));
        }
    }
}

In this example, ComposeBlockchains is a method that takes the magic numbers for each respective blockchain and returns a zipped observable stream that emits tuples of blocks from each blockchain as they are produced. Subscribers to this stream receive updates from all three blockchains in real-time, allowing for complex operations such as cross-chain analysis or aggregate ledger updates.

Considerations

When composing multiple blockchains:

• Synchronization: Ensure that the timing of blocks from different chains is accounted for, as blocks may not be produced simultaneously across chains.
• Error Handling: Implement comprehensive error handling to manage potential discrepancies or failures in one or more blockchains.
• Performance: Consider the performance implications of composing multiple streams, as this could introduce overhead in data processing and memory usage.
• Resource Management: Make sure to dispose of subscriptions properly to free up resources and prevent memory leaks.

Conclusion

The composition of multiple blockchain streams in Abacus unlocks the potential for sophisticated multi-chain applications. By abstracting the complexity of individual blockchain operations into a unified reactive model, developers can focus on building innovative features that span across different cryptocurrencies.