This project is part of my participation in the LearnWeb3DAO Streamr Open Data Challenge.
The goal of the challenge is creating a data stream on the decentralized Streamr Network and publish it on The Hub.
Streamr is a fully decentralised and scalable protocol for many to many data pipelines, network analytics and instant messaging.
For this challenge, I will create a Streamr data stream that delivers real-time price updates for Ethereum and Bitcoin in USD. The data will be sourced from CoinGecko API. The stream will be set up to broadcast data at regular intervals, providing an up-to-date feed of the cryptocurrency prices.
- Stream Name: BTC-ETH-USD-Price
- Streamr URL:
0x163b33c875cd58acaeb557fdc00e30e17f826730/btc-eth-usd-price - Project link: ETH and BTC price in USD
- Frequency: Updated every 5 minutes (Working in Progress)
- Output data format: JSON
- Data Structure:
{ "bitcoin": {"usd":26004}, "ethereum": {"usd":1656.13}, "timestamp": 1692719868 }
- I'm working to host the code online on Vercel in order to automate the data update on the streamr through the cronjob as shown at the end of this Readme. At the moment I have some problems getting the script to work on Vercel and I'm waiting for the client to be updated to the new version to verify its correct functioning and the fix of the problem I reported on Discord.
To use this project, follow these steps:
- Clone this repository to your local machine.
- Set up your development environment by creating a
.envfile. - Run
npm installto install required packages and dependencies.
- create-new-streamr.js
This script creates a new stream on the Streamr Network and print the corresponding URL. This action requires MATIC Tokens for processing.
To run the script, execute the following command:
node create-new-streamr.jsAfter running the script:
- Go to the Streamr Hub and log in.
- Click on "Your streams" and click on your new streamr.
- Modify the access control settings to "Public".
- Set up description, data storage and specify the number of historical days.
- Save your changes.
- Create the project on Projects
- Insert image, description and select the streamrs created above and publish it.
Note: These actions will trigger transactions that incur a cost of 2-3 cents in MATIC Tokens.
- update-streamr.js
This script retrieves data from the specified API and sends it to the Streamr stream.
To run the script, execute the following command:
node update-streamr.jsRemember to adjust any placeholders or details in the instructions to match your actual project setup.
- listen.js
This script demonstrates how to listen to the streamr and retrieve updated price data.
To run the script, execute the following command:
node listen.js- server.js
To make the data updating process automated and accessible online, I've created a simple web server using Express with the server.js file. This server hosts the code that sends data to Streamr, and it can be accessed via an endpoint that triggers the data update.
The endpoint on express server for triggering the data update is /api/update-streamr. However, access to this endpoint is restricted to a predefined list of allowed IP addresses for security reasons.
To further streamline the data updating process, you can set up a cron job that periodically accesses the endpoint and triggers the script execution. This can be achieved by configuring a cron job to make a GET request to the endpoint URL at specified intervals.
*/5 * * * * curl -X GET "https://your-server.com/api/update-streamr"Notes: You have to install express with the command npm install express, update the file server.js with the ip where you hosting the cronjob script or the ip of the service you use to run the job.
If you would like to contribute to this project, feel free to submit a pull request. Contributions are welcome!
This project is licensed under the MIT License.