vCluster Plugin Example

This example plugin syncs car crds from the vcluster into the host cluster.

For more information how to develop plugins in vcluster and a complete walk through, please refer to the official vcluster docs.

Using the Plugin

To use the plugin, create a new vcluster with the plugin.yaml:

# Apply cars crd in host cluster
kubectl apply -f https://raw.githubusercontent.com/loft-sh/vcluster-plugin-example/main/manifests/crds.yaml

# Use public plugin.yaml
vcluster create my-vcluster -n my-vcluster -f https://raw.githubusercontent.com/loft-sh/vcluster-plugin-example/main/plugin.yaml

This will create a new vcluster with the plugin installed. After that, wait for vcluster to start up and check:

# Create a car in the virtual cluster
vcluster connect my-vcluster -n my-vcluster -- kubectl apply -f manifests/audi.yaml

# Check if the car was synced to the host cluster
kubectl get car -n my-vcluster

Building the Plugin

To just build the plugin image and push it to the registry, run:

# Build
docker build . -t my-repo/my-plugin:0.0.1

# Push
docker push my-repo/my-plugin:0.0.1

Then exchange the image in the plugin.yaml.

Development

General vcluster plugin project structure:

.
├── go.mod              # Go module definition
├── go.sum
├── devspace.yaml       # Development environment definition
├── devspace_start.sh   # Development entrypoint script
├── Dockerfile          # Production Dockerfile 
├── main.go             # Go Entrypoint
├── plugin.yaml         # Plugin Helm Values
├── syncers/            # Plugin Syncers
└── manifests/          # Additional plugin resources

Before starting to develop, make sure you have installed the following tools on your computer:

• docker
• kubectl with a valid kube context configured
• helm, which is used to deploy vcluster and the plugin
• vcluster CLI v0.6.0 or higher
• DevSpace, which is used to spin up a development environment
• Go programming language build tools

After successfully setting up the tools, start the development environment with:

devspace dev -n vcluster

After a while a terminal should show up with additional instructions. Enter the following command to start the plugin:

go build -mod vendor -o plugin main.go && /vcluster/syncer start

You can now change a file locally in your IDE and then restart the command in the terminal to apply the changes to the plugin.

Delete the development environment with:

devspace purge -n vcluster