Examples & Tutorials

Learn how to build production-ready applications for Polkadot System Chains with practical examples and step-by-step guides.

System Chain Patterns

Native Asset Monitoring (Asset Hub)

Subscribe to balance changes on Asset Hub for a specific account:

use apex_sdk::prelude::*;
use apex_sdk::substrate::AssetManager;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let asset_mgr = AssetManager::connect_env().await?;
    let account = "5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY".parse()?;

    // Monitor DOT balance (Asset ID 0)
    let mut stream = asset_mgr.watch_balance(account, 0).await?;
    
    while let Some(balance) = stream.next().await {
        println!("New balance: {balance}");
    }

    Ok(())
}

Smart Contract Interaction (PolkaVM/Revive)

Call a Solidity contract method on the Revive protocol:

use apex_sdk::prelude::*;
use apex_sdk::polkavm::ContractManager;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let contract_mgr = ContractManager::connect_env().await?;
    let contract_addr = "0x...".parse()?;
    
    // Attach to an existing contract
    let contract = contract_mgr.attach(contract_addr);
    
    // Call a read-only method
    let total_supply: U256 = contract.call("totalSupply", ()).await?;
    println!("Total Supply: {total_supply}");

    Ok(())
}

Step-by-Step Tutorials

Tutorial: Building an Asset Hub Portfolio Bot

Difficulty: Beginner | Duration: 20 mins

A CLI tool that aggregates all your assets on Asset Hub and monitors for incoming transfers.

1. Setup: Initialize a new project with apex new portfolio-bot --template asset-hub.
2. Implementation: Use the AssetManager to list all registered assets and their balances.
3. Monitoring: Implement a background loop to watch for Transfer events.

Tutorial: Asset Recovery with Revive

Difficulty: Intermediate | Duration: 45 mins

Learn how to use the Revive protocol adapter to implement secure asset recovery patterns.

1. Concept: Understand the Revive recovery mechanism.
2. Integration: Set up a recovery contract on the Revive testnet.
3. Execution: Use ReviveAdapter to trigger a recovery process and verify the outcome.

Code Repository

All examples and advanced tutorials are available in our GitHub Examples Repository:

• asset-transfer: Simple DOT and custom asset transfers.
• nft-gallery: Minting and displaying NFTs from Asset Hub.
• revive-recovery: Implementing the Revive protocol recovery flow.
• system-chain-oracle: Building a lightweight oracle on a system chain.

Next Steps

• Quick Start Guide
• API Reference
• Architecture Overview