Cloudflare Workers - Blue / Green Deployments

This repo contains a minimal example from a proof of concept using the Serverless framework to enable blue / green deployments for Cloudflare Workers.

Configuration

The configuration is handled by dotenv so the first thing you need to do is add a .env file to the root of the repo with the following environment variables:

Variable	Comment
CLOUDFLARE_ACCOUNT_ID	This should be set to your Cloudflare Account ID and can be found in the Overview page under the API section in the Cloudflare dashboard.
CLOUDFLARE_ZONE_ID	This should be set to your Cloudflare Zone ID and can be found in the Overview page under the API section in the Cloudflare dashboard.
CLOUDFLARE_AUTH_KEY	This should be set to your API key which you can find in the Cloudflare dashboard under the API section and then Get your API token -> API tokens tab -> Global API Key
CLOUDFLARE_AUTH_EMAIL	This should be set to the email address you use to sign into your Cloudflare account.
HOST	This should be set to the API host you want to use in your routes, i.e. api.somewhere.com.

Note: You need to ensure you have the required DNS records and TLS certs configured. For example, if your HOST is api.somewhere.com, you need the following DNS A records for the somewhere.com domain to support api.somewhere.com, blue.api.somewhere.com and green.api.somewhere.com, your TLS cert should also have those domains as alternative names, or be a wildcard cert.

Installation

> npm install

Running

I've created some npm scripts to simplify the commands when wrapped with configuration. Replace somewhere.com with the host you configured in the .env file below:

Initial deploy to the default slot (blue):

> npm run deploy
> curl https://blue-api.somewhere.com/account
> "Processing account resource from blue slot..."

Activate the blue slot:

> npm run activate-slot:blue
> curl https://api.somewhere.com/account
> "Processing account resource from blue slot..."

Deploy to the other slot (green):

> npm run deploy
> curl https://green-api.somewhere.com/account
> "Processing account resource from green slot..."

Rotate to the other slot:

> npm run rotate
> curl https://api.somewhere.com/account
> "Processing account resource from green slot..."

Remove all slots/workers:

> npm run remove