kubevela/docs/examples/registry/webserver.yaml

apiVersion: core.oam.dev/v1beta1
kind: ComponentDefinition
metadata:
  name: webserver
  annotations:
    definition.oam.dev/description: "webserver was composed by deployment and service"
spec:
  workload:
    definition:
      apiVersion: apps/v1
      kind: Deployment
  schematic:
    cue:
      template: |
        output: {
          apiVersion: "apps/v1"
          kind:       "Deployment"
          spec: {
              selector: matchLabels: {
                  "app.oam.dev/component": context.name
              }
              template: {
                  metadata: labels: {
                      "app.oam.dev/component": context.name
                  }
                  spec: {
                      containers: [{
                          name:  context.name
                          image: parameter.image

                          if parameter["cmd"] != _|_ {
                              command: parameter.cmd
                          }

                          if parameter["env"] != _|_ {
                              env: parameter.env
                          }

                          if context["config"] != _|_ {
                              env: context.config
                          }

                          ports: [{
                              containerPort: parameter.port
                          }]

                          if parameter["cpu"] != _|_ {
                              resources: {
                                  limits:
                                      cpu: parameter.cpu
                                  requests:
                                      cpu: parameter.cpu
                              }
                          }
                      }]
              }
              }
          }
        }
        // workload can have extra object composition by using 'outputs' keyword
        outputs: service: {
          apiVersion: "v1"
          kind:       "Service"
          spec: {
              selector: {
                  "app.oam.dev/component": context.name
              }
              ports: [
                  {
                      port:       parameter.port
                      targetPort: parameter.port
                  },
              ]
          }
        }
        parameter: {
          image: string
          cmd?: [...string]
          port: *80 | int
          env?: [...{
              name:   string
              value?: string
              valueFrom?: {
                  secretKeyRef: {
                      name: string
                      key:  string
                  }
              }
          }]
          cpu?: string
        }