Polkadot Telemetry

Overview

This repository contains both the backend ingestion server for Substrate Telemetry as well as the Frontend you typically see running at telemetry.polkadot.io.

The backend is a Rust project and the frontend is React/Typescript project.

Getting Started

To run the backend, you will need cargo to build the binary. We recommend using rustup.

To run the frontend make sure to grab the latest stable version of node and install dependencies before doing anything:

nvm install stable
yarn

Terminal 1 - Backend

cd backend
cargo build --release
./target/release/telemetry --help

By default, telemetry will listen on the local interface only (127.0.0.1) on port 8000. You may change both those values with the --listen flag as shown below:

telemetry --listen 0.0.0.0:8888

This example listen on all interfaces and on port :8888

Terminal 2 - Frontend

cd frontend
yarn install
yarn start

Terminal 3 - Node

Follow up installation instructions from the Polkadot repo

polkadot --dev --telemetry-url ws://localhost:8000/submit

Docker

Pre-built docker images are available at parity/substrate-telemetry-frontend and parity/substrate-telemetry-backend.

Run the backend and frontend

Obviously, the frontend need to be aware of the backend. In a similar way, your node will need to connect to the backend. For the sake of brevity below, I will name the containers backend and frontend. In a complex environment, you will want to use names such as telemetry-backend for instance to avoid conflicts with other backend containers.

Let's start the backend first. We will be using the published chevdor images here, feel free to replace with your own image.

docker run --rm -i --name backend -p 8000:8000 \
  chevdor/substrate-telemetry-backend -l 0.0.0.0:8000

Let's now start the frontend:

docker run --rm -i --name frontend --link backend -p 80:80 \
  -e SUBSTRATE_TELEMETRY_URL=ws://localhost:8000/feed \
  chevdor/substrate-telemetry-frontend

WARNING: Do not forget the /feed part of the URL...

NOTE: Here we used SUBSTRATE_TELEMETRY_URL=ws://localhost:8000/feed. This will work if you test with everything running locally on your machine but NOT if your backend runs on a remote server. Keep in mind that the frontend docker image is serving a static site running your browser. The SUBSTRATE_TELEMETRY_URL is the WebSocket url that your browser will use to reach the backend. Say your backend runs on a remore server at 192.168.0.100, you will need to set the IP/url accordingly in SUBSTRATE_TELEMETRY_URL.

At that point, you can already open your browser at http://localhost and see that telemetry is waiting for data.

Let's bring some data in with a node:

docker run --rm -i --name substrate --link backend -p 9944:9944 \
  chevdor/substrate substrate --dev --telemetry-url 'ws://backend:8000/submit 0'

You should now see your node showing up in your local telemetry frontend:

Run via docker-compose

To run via docker make sure that you have Docker Desktop. If you don't you can download for you OS here Docker Desktop

docker-compose up --build -d

• -d stands for detach, if you would like to see logs I recommend using Kitmatic or don't use the -d
• --build will build the images and rebuild, but this is not required every time
• If you want to makes UI changes, there is no need to rebuild the image as the files are being copied in via volumes.

Now navigate to http://localhost:3000 in your browser to view the app.

Build & Publish the Frontend docker image

The building process is standard. You just need to notice that the Dockerfile is in ./packages/frontend/ and tell docker about it. The context must remain the repository's root though.

DOCKER_USER=chevdor ./scripts/build-docker-frontend.sh