Extensions | Runtime Conditions

What an extension owns

Extension Part	What It Does	Example
`kinds`	Defines Condition categories.	`api`, `datastore`, `cache`
`interfaceTypes`	Defines valid interface types for a kind.	`http` for `api`, `key_value` for `cache`
`interfaceFields`	Defines extension-owned fields inside `interface`.	`interface.engine`, `interface.operations`
`fieldValues`	Defines allowed values for extension-owned fields.	`redis`, `memcached`, `GET`, `POST`
`schemas`	Defines machine-readable validation.	JSON Schema for HTTP API Conditions

First-party extension: Common Integrations

The Common Integrations extension defines standard integration vocabulary for APIs, datastores, and caches. Profiles that use `kind: cache` or `interface.type: http` depend on this extension.

extensions/common-integrations/common-integrations-v1alpha1.yaml source

metadata:
  uri: https://runtimeconditions.io/extensions/common-integrations
  version: v1alpha1

spec:
  kinds:
    - name: api
    - name: datastore
    - name: cache

  interfaceTypes:
    - name: http
      targetKind: api
    - name: key_value
      targetKind: cache

Field values make vocabulary deterministic

The extension does not merely say an engine field may exist. It also owns the shared values that validators and adapters can rely on.

Cache engine values

fieldValues:
  - field: interface.engine
    targetKind: cache
    targetType: key_value
    values:
      - redis
      - memcached

HTTP method values

fieldValues:
  - field: interface.operations[].method
    targetKind: api
    targetType: http
    values:
      - GET
      - HEAD
      - POST
      - PUT
      - PATCH
      - DELETE
      - OPTIONS
      - TRACE

Extensions define JSON Schema validation

Schema rules make extension validation portable. The validator can evaluate the profile without interpreting prose.

HTTP API schema excerpt

schemas:
  - id: api-http-interface
    appliesToKind: api
    appliesToInterfaceType: http
    description: Validates HTTP API integration conditions.
    schema:
      type: object
      required:
        - kind
        - interface
      properties:
        kind:
          const: api
        interface:
          type: object
          required:
            - type
          properties:
            type:
              const: http
            operations:
              type: array
              items:
                required:
                  - method
                  - path

First-party extension: Environment Configuration

The Environment Configuration extension adds the `configuration` field. It lets a profile say which workload-facing inputs are expected without embedding the values.

extensions/env-configuration/env-configuration-v1alpha1.yaml source

spec:
  dependencies:
    - https://runtimeconditions.io/extensions/common-integrations:v1alpha1

  conditionFields:
    - name: configuration
      appliesToAllKinds: true

  fieldValues:
    - field: configuration.env[].property
      targetKind: cache
      targetType: key_value
      values:
        - url
        - hostname
        - port
        - username
        - password
        - token

How a profile uses extensions

The profile declares every extension required to interpret its vocabulary. Transitive dependencies are resolved by validators and tooling, but generated profiles should still declare the vocabulary they directly use.

Profile declaration and extension-owned fields

extensions:
  - https://runtimeconditions.io/extensions/common-integrations:v1alpha1
  - https://runtimeconditions.io/extensions/env-configuration:v1alpha1

conditions:
  - name: request-cache
    kind: cache              # common-integrations
    interface:
      type: key_value        # common-integrations
      engine: redis          # common-integrations field value
    configuration:           # env-configuration
      alternatives:
        - env:
            - property: url  # env-configuration field value
              name: REDIS_URL

Third-party extensions follow the same rules

The AWS Object Store extension is treated as a third-party example. It defines `aws.object_store`, `aws.s3`, S3-specific fields, and depends on first-party configuration vocabulary.

extensions/aws-object-store/aws-object-store-v1alpha1.yaml source

metadata:
  uri: https://aws.example.com/runtimeconditions/object-store
  version: v1alpha1

spec:
  dependencies:
    - https://runtimeconditions.io/extensions/common-integrations:v1alpha1
    - https://runtimeconditions.io/extensions/env-configuration:v1alpha1

  kinds:
    - name: aws.object_store

  interfaceTypes:
    - name: aws.s3
      targetKind: aws.object_store