Alchemy: Build a dApp That Provides Real-Time Ethereum Transaction Notifications
Learn how to build a dApp that provides real-time Ethereum transaction notifications.
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Learn how to build a dApp that provides real-time Ethereum transaction notifications.
Last updated
Was this helpful?
Was this helpful?
Decentralized applications, known as dApps, are open-source applications developed using cryptocurrency and smart contracts, then deployed on a blockchain network.
In this tutorial, we’ll launch an example dApp built with Heroku on the Ethereum Testnet Rinkeby. Then, we’ll register our Rinkeby wallet address to opt-in to receiving transaction notifications, then we’ll send a transaction to test our app.
Read below to learn how to build a dApp that provides real-time Ethereum transaction notifications.
This tool is available on a Linux or macOS system.
Set up a credentials file for S3FS at ${HOME}/.passwd-s3fs. You will need to save your Filebase Access and Secret keys to this file and give it owner permissions. You can do so with the following commands:
echo ACCESS_KEY_ID:SECRET_ACCESS_KEY > ${HOME}/.passwd-s3fs
chmod 600 ${HOME}/.passwd-s3fs
ACCESS_KEY_ID is your Filebase Access key, and SECRET_ACCESS_KEY is your Filebase Secret key. For more information on Filebase access keys, see here.
You can mount a Filebase IPFS bucket with the command:
s3fs mybucket /path/to/mountpoint -o passwd_file=${HOME}/.passwd-s3fs -o url=https://s3.filebase.com
mybucket: name of your Filebase bucket
/path/to/mountpoint
Create a new folder for your project:
mkdir notifyTutorial
cd notifyTutorial
git clone https://github.com/alchemyplatform/Alchemy-Notify-Tutorial
cd Alchemy-Notify-Tutorial
If you don’t have an account, sign up for one here.
heroku login
heroku create
Take note of the URL that is returned to the screen. It will be in the format:
https://salty-ridge-48849.herokuapp.com/
Chain: Ethereum
Network: Göerli
Webhook URL: Your Heroku URL from Step 7.
Ethereum Address: Your Ethereum Rinkeby Wallet Address
Then select ‘Create Webhook’.
Copy the webhook ID, we’ll use this in the next step.
server.js file in your working directory. Replace the following lines:In line 37, replace “webhook-id” with your webhook ID.
const body = { webhook_id: “webhook-id”, addresses_to_add: [new_address], addresses_to_remove: [] };
In line 43, replace “Alchemy-auth-key” with your Alchemy authentication token. You can view this token by selecting the ‘Auth Token’ button in the upper right corner of the dashboard.
headers: { 'X-Alchemy-Token': “Alchemy-auth-key”}
git add .
git commit -m "added Alchemy keys"
git push heroku master
This is the URL that is in the format https://salty-ridge-48849.herokuapp.com/
Your app will look like this:
Authorize the connection through the Metamask extension.
Your account address will be listed.
A prompt will confirm that notifications are enabled for your connected wallet address.
