Add configs section to App CRD (#38)

* Add configs section to App CRD

* Update CHANGELOG.md

* Add configs section to App CRD struct definition

* Add updated description for repositories field of Catalog CRD to the struct as well

* Regenerate App CRD yaml and deepcopy

* Add priority field to App CRD extraConfigs

* Regenerate App CRD yaml and deepcopy

* Ignore unused constants about App CRD config layer priority levels

These will be used in merging logics and makes sense to keep with the actual
configuration.

* Set configMap as the default value for kind of extra config entries of App CRD

CHANGELOG.md

@@ -9,6 +9,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Add `configs` section to `App` CRD based on RFC: https://github.com/giantswarm/rfc/tree/main/multi-layer-app-config#enhancing-app-cr
+
 ## [0.4.1] - 2022-06-30
 
 ## [0.4.1] - 2022-06-30

api/v1alpha1/app_types.go

@@ -9,6 +9,14 @@ import (
 const (
 	kindApp              = "App"
 	appDocumentationLink = "https://docs.giantswarm.io/ui-api/management-api/crd/apps.application.giantswarm.io/"
+
+	// NOTE: These should match the kubebuilder annotations set on AppExtraConfig
+	configPriorityDistance = 50
+	configPriorityCatalog  = 0
+	configPriorityDefault  = configPriorityCatalog + configPriorityDistance/2 //nolint
+	configPriorityCluster  = configPriorityCatalog + configPriorityDistance
+	configPriorityUser     = configPriorityCluster + configPriorityDistance
+	configPriorityMaximum  = configPriorityUser + configPriorityDistance //nolint
 )
 
 func NewAppTypeMeta() metav1.TypeMeta {
@@ -68,6 +76,11 @@ type AppSpec struct {
 	Config AppSpecConfig `json:"config,omitempty"`
 	// +kubebuilder:validation:Optional
 	// +nullable
+	// ExtraConfigs is a list of configurations to merge together based on the priority and order in the list.
+	// See: https://github.com/giantswarm/rfc/tree/main/multi-layer-app-config#enhancing-app-cr
+	ExtraConfigs []AppExtraConfig `json:"extraConfigs,omitempty"`
+	// +kubebuilder:validation:Optional
+	// +nullable
 	// Install is the config used when installing the app.
 	Install AppSpecInstall `json:"install,omitempty"`
 	// KubeConfig is the kubeconfig to connect to the cluster when deploying
@@ -106,6 +119,26 @@ type AppSpecConfig struct {
 	Secret AppSpecConfigSecret `json:"secret,omitempty"`
 }
 
+// +k8s:openapi-gen=true
+type AppExtraConfig struct {
+	// +optional
+	// +kubebuilder:validation:Enum=configMap;secret
+	// +kubebuilder:default:=configMap
+	// Kind of configuration to look up that should be applied to the app when deployed.
+	Kind string `json:"kind"`
+	// Name of the resource of the given kind to look up.
+	Name string `json:"name"`
+	// Namespace where the resource with the given name and kind to look up is located.
+	Namespace string `json:"namespace"`
+	// +optional
+	// +kubebuilder:validation:Minimum:=0
+	// +kubebuilder:validation:Maximum:=150
+	// +kubebuilder:default:=25
+	// Priority is used to indicate at which stage the extra configuration should be merged.
+	// See: https://github.com/giantswarm/rfc/tree/main/multi-layer-app-config#enhancing-app-cr
+	Priority int `json:"priority"`
+}
+
 // +k8s:openapi-gen=true
 type AppSpecInstall struct {
 	// +kubebuilder:validation:Optional

api/v1alpha1/catalog_types.go

@@ -58,8 +58,8 @@ type CatalogSpec struct {
 	Config *CatalogSpecConfig `json:"config,omitempty"`
 	// LogoURL contains the links for logo image file for this catalog
 	LogoURL string `json:"logoURL"`
-	// Storage references an object defining catalog repository. Will be
-	// deprecated. Replaced by Repositories.
+	// Storage references an object defining catalog repository.
+	// This field is deprecated and replaced by Repositories.
 	Storage CatalogSpecStorage `json:"storage"`
 	// +kubebuilder:validation:MinItems=1
 	// Repositories is an array of objects defining catalog repositories.

config/crd/application.giantswarm.io_apps.yaml

@@ -109,6 +109,40 @@ spec:
                     - namespace
                     type: object
                 type: object
+              extraConfigs:
+                description: 'ExtraConfigs is a list of configurations to merge together
+                  based on the priority and order in the list. See: https://github.com/giantswarm/rfc/tree/main/multi-layer-app-config#enhancing-app-cr'
+                items:
+                  properties:
+                    kind:
+                      default: configMap
+                      description: Kind of configuration to look up that should be
+                        applied to the app when deployed.
+                      enum:
+                      - configMap
+                      - secret
+                      type: string
+                    name:
+                      description: Name of the resource of the given kind to look
+                        up.
+                      type: string
+                    namespace:
+                      description: Namespace where the resource with the given name
+                        and kind to look up is located.
+                      type: string
+                    priority:
+                      default: 25
+                      description: 'Priority is used to indicate at which stage the
+                        extra configuration should be merged. See: https://github.com/giantswarm/rfc/tree/main/multi-layer-app-config#enhancing-app-cr'
+                      maximum: 150
+                      minimum: 0
+                      type: integer
+                  required:
+                  - name
+                  - namespace
+                  type: object
+                nullable: true
+                type: array
               install:
                 description: Install is the config used when installing the app.
                 nullable: true