Chainlink
Chainlink connects blockchain smart contracts with external data such as prices, identities, or API requests by the use of Chainlink nodes. Nodes watch the Ethereum blockchain for oracle requests and get compensated in LINK for updating the on-chain data. One core use has been the development of decentralized price feeds which you can browse at https://feeds.link
Before you read this
In this guide we will be deploying a Chainlink node to a Kubernetes cluster with the click of a button. If you only wish to run a standalone Chainlink node using Docker, we’d recommend the official documentation.
While many existing official operators use Kubernetes for container orchestration, our deployment will differ by using KubeApps on top of our cluster to enable one-click deployment of our Chainlink node. In the long-term, having KubeApps running can make it easy to upgrade to newer Chainlink versions and also help us deploy add-ons such as an external Chainlink Gas Updater or a Chainlink GraphQL API.
Requirements / Tools
Alright, so we may have lied a teeny weensy bit: this guide will help you deploy a Chainlink node with the click of a button, but only once you have KubeApps running. However, once you do, you will also be able to upgrade to future versions and install add-ons with the simple click of a button.
Here are some of the components we will be using to deploy our Chainlink node. If you’re missing any, keep reading as we will provide suggestions on getting each of these setup. If you have these components setup already, you can skip to the “KubeApps Chainlink Deployment” section on how to deploy the Chainlink node using the GUI.
- Ethereum Node
- PostgreSQL Database
- Kubernetes (K8s) Cluster
- Helm configured with K8s cluster
- KubeApps Deployment on K8s Cluster
Ethereum Node
Your Chainlink node will need an Ethereum Node to watch and fulfill oracle requests on the blockchain. If looking to create a simple deployment we recommend a service such as infura.io or fiews.io which both offer free tiers giving you access to JSON-RPC requests. If looking to maximize security, running your own node is always the better solution. You can even combine an in-house Ethereum node with a Node as a Service (NaaS) thanks to https://github.com/OracleFinder/ChainlinkEthFailover
PostgreSQL Server
The Chainlink Node uses an external PostgreSQL database to keep track of transactions, requests, and other important data required for oracle request execution. If you already have a PostgreSQL server, simply create a new database named “chainlink”. If you do not have a PostgreSQL server, you can either use a service like AWS RDS to setup your database, or use KubeApps to deploy the PostgreSQL Chart (see later section on KubeApps).
Kubernetes (K8s) Cluster
K8s enables container orchestration. Container orchestration is the dynamic management of a cluster of containers. Once you have a cluster up and running, you’ll be able to deploy multiple independent docker containers. While you could deploy a PostgreSQL and Chainlink docker container directly using the K8s API, Helm and KubeApps will greatly simplify this process by storing our configuration and adding a UI Layer.
If you do not have a K8s cluster you can use a cloud service such as AWS EKS or if looking for a light-weight solution for your own server, you can checkout MicroK8s https://microk8s.io/
Helm
Once you have your K8s cluster running, we will install Helm. Helm uses “charts” which store configuration on your software’s K8s deployment architecture. Charts can then be shared through repositories.
Use the Helm Quickstart guide to install Helm v3 on your K8s cluster.
You can find the Vulcan Link charts at https://github.com/vulcanlink/charts (in development). While you could use the Helm CLI to deploy these charts, KubeApps will let you deploy these with a more intuitive frontend.
KubeApps
KubeApps is an opensource UI front-end developed by Bitnami designed to help you manage your K8s deployments. Once KubeApps is deployed on your K8s cluster, you will be able to deploy Helm charts with the click of a button. Follow the Quickstart guide to install KubeApps on your K8s cluster using Helm v3.
KubeApps Chainlink Deployment
Using KubeApps
Now that KubeApps is running, this is where the magic happens. If you followed the KubeApps Getting Started guide you should be able to access KubeApps at http://localhost:8080.
If you can’t, make sure you are port forwarding the kubeapps service.
kubectl port-forward -n kubeapps svc/kubeapps 8080:80The “Applications” page will show you Helm charts currently deployed on your cluster.
The “Catalog” page lists possible charts you can choose to deploy on your cluster, a kind of App Store for K8s deployments.
If you wish to deploy a PostgreSQL server on your K8s cluster, you can do so by searching PostgreSQL and deploying the respective chart. Keep reading as the steps for this will be similar as to how we deploy the Chainlink node.
At the top right, you can switch between different namespaces on you cluster. In general, simply use the “default” namespace for your deployments.
Adding the Vulcan Link Chart Repo
The Chainlink node isn’t part of the Catalog as the “@stable” repository does not contain a Chainlink chart. However, Vulcan Link has created a helm chart for Chainlink, and deployed it to our own independent Helm repository hosted on GitHub.
To add the Vulcan Link repo, first change the namespace to “All Namespaces” to add the repo to all namespaces. Go to “Configuration > App Repositories”.
Click “Add App Repository” and use these values:
name: vulcanlink
url: https://vulcanlink.github.io/charts/You should now be able to view the Vulcan Link charts on the Catalog page. To test this, simply type “vulcanlink” in the Catalog search bar.
Deploying a Chainlink Node
Switch the namespace back to “default”, select the “chainlink” chart, and click “Deploy”.
You can now use the form to enter your environment variables such as the URLs to the Ethereum Node and PostgreSQL database. You can also add additional environment variables by editing the config key under the Values section.
After clicking submit, your Chainlink deployment should pop up in the “Applications” section.
Of course, CLI commands should also show you that the Chainlink node has been correctly deployed.
kubectl get deployments #Using K8s API
helm ls #Using HelmTo get access to the Chainlink UI, follow the commands from “Notes”:
1. Get the application URL by running these commands:
export POD_NAME=$(kubectl get pods --namespace default -l "app.kubernetes.io/name=chainlink,app.kubernetes.io/instance=panoramic-shape" -o jsonpath="{.items[0].metadata.name}")
echo "Visit http://127.0.0.1:8080 to use your application"
kubectl --namespace default port-forward $POD_NAME 8080:6688You might have to change the 8080 port to 8081 if you are already serving KubeApps on 8080
You should now be able to visit the Chainlink Node dashboard at http://localhost:8080
The END
That’s it! Your Chainlink node is deployed! All there is left to do now is setting up an on-chain Oracle contract and funding your node to start Fulfilling Requests.
About Vulcan Link
We are a Paris-based Chainlink node operator working on actively maintaining 30+ reliable data feeds and developing decentralized applications that leverage smart contracts with external data. We believe in building trust through transparency by contributing to opensource projects. If you’d like us to add other data feeds to feeds.link, feel free to reach out through our links below!
Find us at vulcan.link
Follow us on Twitter @vulcanlink for updates on new projects like this one.
If you’d like to contribute, join us on Telegram and Discord
