eCash

— <a href="https://twitter.com/bytesofman" rel="noopener noreferrer nofollow">Joey</a>, lead dev, CashtabLast month, I wrote about <a href="https://e.cash/blog/building-on-ecash-2022-12" rel="noopener noreferrer nofollow">available tools and libraries for developers</a> looking to get started with eCash. This month, let’s put together a quick demo app using the chronik indexer.Here are some basic bash command prompt instructions. You will need <a href="https://github.com/nvm-sh/nvm" rel="noopener noreferrer nofollow">nodejs</a> to follow the example here.First, we create the directory for our app, initialize an npm module, install chronik, and create our first script.<img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/810141afc24c46d98bb2e39870426f40.jpg" />Next, let&#39;s write a function that queries chronik for information about a transaction.<img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/75d10cdac0fb44f1bc431caaf98052e7.jpg" />Now we can run the script from the command line by entering a txid as an env variable.<img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/8cdd3b1b57c44178a64f6192871eba71.jpg" />Great! Now we can use this script to get tx details for any given txid.What else can we do with chronik?To build a basic wallet app, you need to know how much eCash is available to spend at the wallet&#39;s address. Spendable eCash is stored in objects called &#34;utxos,&#34; or &#34;unspent transaction outputs.&#34; Let’s write a simple script to get utxos from a wallet:<img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/c1da535320cb42ebbc3e1e155738a8ef.jpg" /><img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/3b9ff8e0e9ea48afbb2c5e3b51a42a7d.jpg" />While we are used to thinking of wallets and addresses, chronik accesses information about an address at a lower level. So, for a typical wallet address, we’ll need to first get the hash160 before we can see its utxo set. Let&#39;s write a helper function to get the hash160 from an eCash address.<img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/e01affb7c29e4dba8acd49f26d55395e.jpg" /><img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/ce18b935217e449fb33f179a6892b138.jpg" />Now we can go back and include the helper function addressToHash160 in getUtxosFromAddress.js<img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/a2b5253bb4634370a59accb2cc1087c0.jpg" />...so now, we can get the utxo set of an eCash address by running this script from the command line.<img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/09d30212087e4da9972f1af28219ca4f.jpg" />Great! What about tx history?<img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/4124d7febd3741d6afa9f53ee96465b2.jpg" /><img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/7efcf8ebe14f4d359c3a44042061adae.jpg" /><img src="https://academy-public.coinmarketcap.com/srd-optimized-uploads/6639adad9ec24584a209f07370710732.jpg" />The final app is available <a href="https://github.com/BytesOfMan/chronik-node-testdrive" rel="noopener noreferrer nofollow">here.</a> You could also check out <a href="https://github.com/Bitcoin-ABC/bitcoin-abc/tree/master/web/cashtab" rel="noopener noreferrer nofollow">Cashtab&#39;s source code</a> to see how to use chronik in a React app. Or check out the <a href="https://t.me/eCashDevelopment" rel="noopener noreferrer nofollow">eCash development telegram chat</a> if you have any questions about using these tools to build on eCash.Originally Published: <a href="https://e.cash/blog/building-on-ecash-january-2023" rel="noopener noreferrer nofollow">Building on eCash: Creating a Demo App Using the Chronik Indexer</a>

Building on eCash: Creating a Demo App Using the Chronik Indexer

eCash

Other articles published on Jan 30, 2023

Blockchain games defy the bear market as GameFi overtakes DeFi

Data Lake records the first Data Flow from a hospital on-chain!

Andrew Tate a promovat Bitcoin ca modalitate de evaziune fiscală

Soccer Crypto Released Staking Features

Top 7 Web 3.0 Crypto Altcoins With Absurd Potential

Ethereum Shanghai Mainnet Shadow Fork has Gone Live

Join our free newsletter for daily crypto updates!