CASMCMS-8965: Update sessions controller to provide error responses c…

…onsistently and correctly

CHANGELOG.md

@@ -11,6 +11,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - CASMCMS-9274: Prevent [`SNYK-PYTHON-WERKZEUG-6808933`](https://security.snyk.io/vuln/SNYK-PYTHON-WERKZEUG-6808933) from causing builds to fail.
 - CASMCMS-9265: Improve Python type annotations in sessions controller code
 
+### Fixed
+- CASMCMS-8965: Update sessions controller to provide error responses consistently and correctly
+
 ### Dependencies
 - Bumped Python dependency versions.
 

api/openapi.yaml.in

@@ -263,39 +263,6 @@ components:
         example: "Compute"
         minLength: 1
         maxLength: 127
-    ProblemDetails:
-      description: An error response for RFC 7807 problem details.
-      type: object
-      properties:
-        type:
-          description: |
-            Relative URI reference to the type of problem which includes human
-            readable documentation.
-          type: string
-          format: uri
-          default: "about:blank"
-        title:
-          description: |
-            Short, human-readable summary of the problem, should not change by
-            occurrence.
-          type: string
-        status:
-          description: HTTP status code
-          type: integer
-          example: 400
-        instance:
-          description: |
-            A relative URI reference that identifies the specific occurrence of
-            the problem
-          format: uri
-          type: string
-        detail:
-          description: |
-            A human-readable explanation specific to this occurrence of the
-            problem. Focus on helping correct the problem, rather than giving
-            debugging information.
-          type: string
-      additionalProperties: false
     SessionLimit:
       type: string
       description: |
@@ -1115,6 +1082,104 @@ components:
       minProperties: 1
       maxProperties: 1024
 
+    # Error response schemas
+    ProblemDetails:
+      description: An error response for RFC 7807 problem details.
+      type: object
+      properties:
+        type:
+          description: |
+            Relative URI reference to the type of problem which includes human
+            readable documentation.
+          type: string
+          format: uri
+          default: "about:blank"
+        title:
+          description: |
+            Short, human-readable summary of the problem, should not change by
+            occurrence.
+          type: string
+        status:
+          description: HTTP status code
+          type: integer
+          example: 400
+        instance:
+          description: |
+            A relative URI reference that identifies the specific occurrence of
+            the problem
+          format: uri
+          type: string
+        detail:
+          description: |
+            A human-readable explanation specific to this occurrence of the
+            problem. Focus on helping correct the problem, rather than giving
+            debugging information.
+          type: string
+      additionalProperties: false
+    # OAS 3.0 does not support constant values
+    # The closest we can do is single-value enum + default
+    ProblemAlreadyExists:
+      type: object
+      properties:
+        title:
+          type: string
+          enum: [ "The resource to be created already exists" ]
+          default: "The resource to be created already exists"
+        status:
+          type: integer
+          enum: [ 409 ]
+          default: 409
+      additionalProperties: true
+    ProblemBadRequest:
+      type: object
+      properties:
+        title:
+          type: string
+          enum: [ "Bad Request" ]
+          default: "Bad Request"
+        status:
+          type: integer
+          enum: [ 400 ]
+          default: 400
+      additionalProperties: true
+    ProblemResourceNotFound:
+      type: object
+      properties:
+        title:
+          type: string
+          enum: [ "The resource was not found" ]
+          default: "The resource was not found"
+        status:
+          type: integer
+          enum: [ 404 ]
+          default: 404
+      additionalProperties: true
+    ProblemUpdateConflict:
+      type: object
+      properties:
+        title:
+          type: string
+          enum: [ "The update was not allowed due to a conflict" ]
+          default: "The update was not allowed due to a conflict"
+      additionalProperties: true
+    ProblemServiceUnavailable:
+      type: object
+      properties:
+        title:
+          type: string
+          enum: [ "Service Unavailable" ]
+          default: "Service Unavailable"
+      additionalProperties: true
+    ProblemInternalError:
+      type: object
+      properties:
+        title:
+          type: string
+          enum: [ "An Internal Server Error occurred handling the request" ]
+          default: "An Internal Server Error occurred handling the request"
+      additionalProperties: true
+
+
   requestBodies:
     V2sessionCreateRequest:
       description: The information to create a Session
@@ -1249,57 +1314,56 @@ components:
         application/json:
           schema:
             $ref: '#/components/schemas/V2Options'
+
     # Errors
     AlreadyExists:
       description: The resource to be created already exists
       content:
         application/problem+json:
           schema:
-            $ref: '#/components/schemas/ProblemDetails'
+            allOf:
+              - $ref: '#/components/schemas/ProblemDetails'
+              - $ref: '#/components/schemas/ProblemAlreadyExists'
     BadRequest:
       description: Bad Request
       content:
         application/problem+json:
           schema:
-            $ref: '#/components/schemas/ProblemDetails'
-    BadRequestOrMultiTenancyNotSupported:
-      description: |
-        Multi-tenancy is not supported for this request.
-        If no tenant was specified, then the request was bad for another reason.
-      content:
-        application/problem+json:
-          schema:
-            $ref: '#/components/schemas/ProblemDetails'
-    MultiTenancyNotSupported:
-      description: Multi-tenancy is not supported for this BOS request.
-      content:
-        application/problem+json:
-          schema:
-            $ref: '#/components/schemas/ProblemDetails'
+            allOf:
+              - $ref: '#/components/schemas/ProblemDetails'
+              - $ref: '#/components/schemas/ProblemBadRequest'
     ResourceNotFound:
       description: The resource was not found.
       content:
         application/problem+json:
           schema:
-            $ref: '#/components/schemas/ProblemDetails'
+            allOf:
+              - $ref: '#/components/schemas/ProblemDetails'
+              - $ref: '#/components/schemas/ProblemResourceNotFound'
     UpdateConflict:
       description: The update was not allowed due to a conflict.
       content:
         application/problem+json:
           schema:
-            $ref: '#/components/schemas/ProblemDetails'
+            allOf:
+              - $ref: '#/components/schemas/ProblemDetails'
+              - $ref: '#/components/schemas/ProblemUpdateConflict'
     ServiceUnavailable:
       description: Service Unavailable
       content:
         application/problem+json:
           schema:
-            $ref: '#/components/schemas/ProblemDetails'
+            allOf:
+              - $ref: '#/components/schemas/ProblemDetails'
+              - $ref: '#/components/schemas/ProblemServiceUnavailable'
     InternalError:
       description: An Internal Server Error occurred handling the request.
       content:
         application/problem+json:
           schema:
-            $ref: '#/components/schemas/ProblemDetails'
+            allOf:
+              - $ref: '#/components/schemas/ProblemDetails'
+              - $ref: '#/components/schemas/ProblemInternalError'
 
   parameters:
     TemplateIdPathParam:
@@ -1553,6 +1617,8 @@ paths:
           $ref: '#/components/responses/V2SessionDetails'
         400:
           $ref: '#/components/responses/BadRequest'
+        409:
+          $ref: '#/components/responses/AlreadyExists'
     get:
       summary: List Sessions
       parameters: