Action policy

The Action policy, is an optional policy, which can be provided to a single Action in Capact. This policy can be used:

• in case the User wants to enforce a specific Implementation for an Interface,
• when the User wants to provide additional parameters to an Implementation.

Example

The following YAML snippet presents an Action policy example with additional comments:

interface:
  default: # default configuration for all Interfaces
    inject: # For all Implementations, inject the following TypeInstances if matching Type Reference is used in `Implementation.spec.requires` property along with `alias`.
    # TypeInstances from `default.inject` can be overwritten in rules for specific Interfaces (`interface.rules[].inject`).
      requiredTypeInstances:
        - id: 2016dcdc-e922-22c4-a690-d8ebf929da2d
          description: "AWS Service Account" # optional  
  rules: # Configures the following behavior for Engine during rendering Action
    - interface: # Rules for Interface with exact path
        path: cap.interface.productivity.rocketchat.install
      oneOf:
        - implementationConstraints: # Enforces the Helm Rocket.Chat Implementation
            path: "cap.implementation.rocketchat.helm.install"
          inject:
            additionalParameters: # Injects additional parameters for the Implementation
              - name: additional-parameters # Name must match one of the parameter defined under `additionalInput.parameters` in the Implementation
                value:
                  replicaCount: 3
            additionalTypeInstances: # Injects additional TypeInstances for the Implementation
              - name: sample # Name must match one of the parameter defined under `additionalInput.typeInstances` in the Implementation
                id: 0b6dba9a-d111-419d-b236-357cf0e8603a

    - interface: # Configures a second rule in the Action policy
        path: cap.interface.database.mongodb.install
      oneOf:
        - implementationConstraints:
            path: "cap.implementation.bitnami.mongodb.install"
          inject:
            additionalParameters: # Injects additional parameters for the Implementation
              - name: additional-parameters # Name must match one of the parameter defined under `additionalInput.parameters` in the Implementation
                value:
                  image:
                    registry: docker.io
                    pullPolicy: Always

Provide Action policy, when creating Action using Capact CLI

To provide the Action policy, when creating an Action you can use the --action-policy-from-file flag to the Capact CLI. First, create a YAML file with the desired Action policy, for example:

interface:
  rules:
    - interface:
        path: cap.interface.productivity.rocketchat.install
      oneOf:
        - implementationConstraints:
            path: "cap.implementation.rocketchat.install"
          inject:
            additionalParameters: # Injects additional parameters for the Implementation
              - name: additional-parameters # Name must match one of the parameter defined under `additionalInput.parameters` in the Implementation
                value:
                  replicaCount: 3

To know how to define the policy rules, see the Policy syntax section. Then, provide the path to the created policy YAML file using the --action-policy-from-file flag, when creating the Action:

capact action create \
  cap.interface.productivity.rocketchat.install \
  --action-policy-from-file {path-to-policy-file}