Labels

This section shows how to use the Template Driver for managing labels on Kubernetes objects.

While it is also possible to set labels via Score, the approach shown here shifts the management of labels down to the Platform, ensuring consistency and relieving developers of the task to repeat common labels for each Workload in the Score extension file.

config-labels.yaml: Resource Definition of type config which defines the value for a sample label at a central place.
custom-workload-with-dynamic-labels.yaml: Add dynamic labels to your Workload. This format is for use with the Humanitec CLI.
custom-namespace-with-dynamic-labels.yaml: Add dynamic labels to your Namespace. This format is for use with the Humanitec CLI.

config-labels.yaml (view on GitHub) :

# This "config" type Resource Definition provides the value for the sample label
apiVersion: entity.humanitec.io/v1b1
kind: Definition
metadata:
  id: app-config
entity:
  name: app-config
  type: config
  driver_type: humanitec/template
  driver_inputs:
    values:
      templates:
        # Returns a sample output named "cost_center_id" to be used as a label
        outputs: |
          cost_center_id: my-example-id
  # Match the resource ID "app-config" so that it can be requested via that ID
  criteria:
    - res_id: app-config

custom-namespace-with-dynamic-labels.yaml (view on GitHub) :

# This Resource Definition references the "config" resource to use its output as a label
# and adds another label taken from the Deployment context
apiVersion: entity.humanitec.io/v1b1
kind: Definition
metadata:
  id: custom-namespace-with-label
entity:
  name: custom-namespace-with-label
  type: k8s-namespace
  driver_type: humanitec/template
  driver_inputs:
    values:
      templates:
        init: |
          name: ${context.app.id}-${context.env.id}
        manifests: |-
          namespace.yaml:
            location: cluster
            data:
              apiVersion: v1
              kind: Namespace
              metadata:
                labels:
                  env_id: ${context.env.id}
                  cost_center_id: ${resources['config.default#app-config'].outputs.cost_center_id}
                name: {{ .init.name }}
        outputs: |
          namespace: {{ .init.name }}
  # Set matching criteria as required
  criteria:
    - {}

custom-workload-with-dynamic-labels.yaml (view on GitHub) :

# This Resource Definition references the "config" resource to use its output as a label
# and adds another label taken from the Deployment context
apiVersion: entity.humanitec.io/v1b1
kind: Definition
metadata:
  id: custom-workload-with-label
entity:
  name: custom-workload-with-label
  type: workload
  driver_type: humanitec/template
  driver_inputs:
    values:
      templates:
        # Remove the /spec/service/labels part if there is no "service" in your Score file.
        outputs: |
          update:
            - op: add
              path: /spec/labels
              value:
                {{- range $key, $val := .resource.spec.labels }}
                {{ $key }}: {{ $val | quote }}
                {{- end }}
                env_id: ${context.env.id}
                cost_center_id: ${resources['config.default#app-config'].outputs.cost_center_id}
            - op: add
              path: /spec/service/labels
              value:
                {{- range $key, $val := .resource.spec.service.labels }}
                {{ $key }}: {{ $val | quote }}
                {{- end }}
                env_id: ${context.env.id}
                cost_center_id: ${resources['config.default#app-config'].outputs.cost_center_id}
  # Set matching criteria as required
  criteria:
    - {}

Resource Definitions

Driver

Capability

Labels