APPS-11069: Add spec for app health API (#1006)

* APPS-11069: Add spec for app health API

* fix lint errors

Author: greeshmapill

specification/DigitalOcean-public.v2.yaml

@@ -675,6 +675,10 @@ paths:
     post:
       $ref: "resources/apps/apps_list_metrics_bandwidth_usage.yml"
 
+  /v2/apps/{app_id}/health:
+    get:
+      $ref: "resources/apps/apps_get_health.yml"
+
   /v2/cdn/endpoints:
     get:
       $ref: "resources/cdn/cdn_list_endpoints.yml"

specification/resources/apps/apps_get_health.yml

@@ -0,0 +1,38 @@
+operationId: apps_get_health
+
+summary: Retrieve App Health
+
+description: Retrieve information like health status, cpu and memory utilization of app components.
+
+parameters:
+  - $ref: parameters.yml#/app_id
+
+tags:
+- Apps
+
+responses:
+  "200":
+    $ref: responses/apps_health.yml
+
+  "401":
+    $ref: ../../shared/responses/unauthorized.yml
+
+  "404":
+    $ref: "../../shared/responses/not_found.yml"
+
+  "429":
+    $ref: "../../shared/responses/too_many_requests.yml"
+
+  "500":
+    $ref: ../../shared/responses/server_error.yml
+
+  default:
+    $ref: ../../shared/responses/unexpected_error.yml
+
+x-codeSamples:
+  - $ref: 'examples/curl/apps_get_health.yml'
+
+security:
+  - bearer_auth:
+    - 'app:read'
+

specification/resources/apps/examples/curl/apps_get_health.yml

@@ -0,0 +1,6 @@
+lang: cURL
+source: |-
+  curl -X GET \
+    -H "Content-Type: application/json" \
+    -H "Authorization: Bearer $DIGITALOCEAN_TOKEN" \
+    "https://api.digitalocean.com/v2/apps/{id}/health"

specification/resources/apps/models/app_component_health.yml

@@ -0,0 +1,29 @@
+type: object
+properties:
+  name:
+    type: string
+    example: sample_app
+  cpu_usage_percent:
+    type: number
+    format: double
+    example: 30
+  memory_usage_percent:
+    type: number
+    format: double
+    example: 25
+  replicas_desired:
+    type: integer
+    format: int64
+    example: 1
+  replicas_ready:
+    type: integer
+    format: int64
+    example: 1
+  state:
+    type: string
+    enum:
+      - UNKNOWN
+      - HEALTHY
+      - UNHEALTHY
+    default: UNKNOWN
+    example: HEALTHY

specification/resources/apps/models/app_functions_component_health.yml

@@ -0,0 +1,20 @@
+type: object
+properties:
+  name:
+    type: string
+    example: sample_function
+  functions_component_health_metrics:
+    type: array
+    items:
+      type: object
+      properties:
+        metric_label:
+          type: string
+          example: activations_count
+        metric_value:
+          type: number
+          format: double
+          example: 100
+        time_window:
+          type: string
+          example: 1h

specification/resources/apps/models/app_health.yml

@@ -0,0 +1,10 @@
+type: object
+properties:
+  components:
+    type: array
+    items:
+      "$ref": app_component_health.yml
+  functions_components:
+    type: array
+    items:
+      "$ref": app_functions_component_health.yml

specification/resources/apps/models/app_health_response.yml

@@ -0,0 +1,4 @@
+properties:
+  app_health:
+    "$ref": app_health.yml
+type: object

specification/resources/apps/responses/apps_health.yml

@@ -0,0 +1,17 @@
+description: A JSON with key `app_health` 
+
+content:
+  application/json:
+    schema:
+      $ref: ../models/app_health_response.yml
+    examples:
+      app_health:
+        $ref: examples.yml#/app_health
+
+headers:
+  ratelimit-limit:
+    $ref: ../../../shared/headers.yml#/ratelimit-limit
+  ratelimit-remaining:
+    $ref: ../../../shared/headers.yml#/ratelimit-remaining
+  ratelimit-reset:
+    $ref: ../../../shared/headers.yml#/ratelimit-reset

specification/resources/apps/responses/examples.yml

@@ -912,3 +912,13 @@ app_bandwidth_usage_multiple:
       - app_id: c2a93513-8d9b-4223-9d61-5e7272c81cf5
         bandwidth_bytes: '254847'
     date: 2023-01-17T00:00:00Z
+
+app_health:
+  value:
+    components:
+      - name: sample-expressjs
+        cpu_usage_percent: 5.555
+        memory_usage_percent: 20.32
+        replicas_desired: 1
+        replicas_ready: 2
+        state: HEALTHY