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KoaJS on CloudFlow

Learn how to run a "Hello World" KoaJS app at the edge for low latency and high availability. You can use our repo as a template, or perform the steps yourself using the Kubernetes dashboard or kubectl commands.

Option 1 - Copy Our GitHub Repo​

  1. Make a new repo from our template: in your browser visit https://github.com/section/koajs-template and select Use this template (don't clone, don't fork, but use the template). Choose yourself as an owner, give it a name of your choice, and make it be Public (not Private).
  2. In your new GitHub repo, under Settings > Secrets > Actions, use New repository secret to add these two:
  3. Make a simple change to the value of ctx.body on line 5 of app.js and watch your changes go live.

Every time you push to the repo your project will be built and deployed to CloudFlow automatically using GitHub Actions.

Option 2 - Step by Step​

Following are step-by-step instructions to deploy a KoaJS "Hello World" application to the edge on CloudFlow. We'll Dockerize it, push it to GitHub Packages, and deploy it on CloudFlow.

Prerequisites​

  • You need Docker and Node installed so that you can build a docker image.

Create the KoaJS App​

Create a new directory for your app.

mkdir node-koajs
cd node-koajs

Install the KoaJS application.

npm i koa

And then we add our application code. Create app.js with the following code.

app.js
const Koa = require('koa');
const app = new Koa();

app.use(async ctx => {
  ctx.body = 'Hello World from KoaJS on CloudFlow!';
});

app.listen(3000);

Test it using node app.js and visit it using curl http://localhost:3000. You'll get the "Hello World from KoaJS on CloudFlow!" response.

Dockerize It​

Let's build the container image that we'll deploy to CloudFlow. First make a Dockerfile in your directory with the following content.

Dockerfile
FROM node:lts as runner
WORKDIR /node-koajs
ENV NODE_ENV production
ARG COMMIT_ID
ENV COMMIT_ID=${COMMIT_ID}
COPY . .
RUN npm i koajs
EXPOSE 3000
CMD ["node", "app.js"]

Build and tag it.

docker build . -t ghcr.io/YOUR_GITHUB_USERNAME/node-koajs:prod

Launch it locally to test it.

docker run -p 3000:3000 ghcr.io/YOUR_GITHUB_USERNAME/node-koajs:prod
curl http://localhost:3000

Push It​

Push it to GitHub Packages. This makes it available to CloudFlow.

docker push ghcr.io/YOUR_GITHUB_USERNAME/node-koajs:prod

Be sure to make it public. To see your packages and make this change, visit https://github.com/YOUR_GITHUB_USERNAME?tab=packages

Deploy It​

Next, use the Create Project command in the CloudFlow Console in order to deploy your new container. Use the image name ghcr.io/YOUR_GITHUB_USERNAME/my-koajs-app:prod with port 8080.

See the pods running on CloudFlow's network with either the Kubernetes dashboard or kubectl get pods -o wide. The -o wide switch shows where your app is running according to the default AEE location optimization strategy. Your app will be optimally deployed according to traffic. In lieu of significant traffic, your deployment will be made to default locations.

Try kubectl logs POD to see the log message reporting that the server is listening on port 3000 (App listening at http://localhost:3000)

Finally, follow the instructions that configure DNS and TLS.

See What You've Built​

See the "Hello World" app you've built by visiting the https://YOUR.DOMAIN.COM, substituting YOUR.DOMAIN.COM according to your DNS and HTTPS configuration.