Fix exception raised when patch endpoint receives invalid request

app/controllers/scim_rails/scim_users_controller.rb

@@ -126,9 +126,23 @@ def put_active_param
     end
 
     def patch_active_param
-      active = params.dig("Operations", 0, "value", "active")
-      raise ScimRails::ExceptionHandler::UnsupportedPatchRequest if active.nil?
-      active
+      handle_invalid = lambda do
+        raise ScimRails::ExceptionHandler::UnsupportedPatchRequest
+      end
+
+      operations = params["Operations"] || {}
+
+      valid_operation = operations.find(handle_invalid) do |operation|
+        valid_patch_operation?(operation)
+      end
+
+      valid_operation.dig("value", "active")
+    end
+
+    def valid_patch_operation?(operation)
+      operation["op"] == "replace" &&
+        operation["value"] &&
+        operation["value"]["active"]
     end
   end
 end

spec/controllers/scim_rails/scim_users_controller_spec.rb

@@ -569,6 +569,53 @@
         response_body = JSON.parse(response.body)
         expect(response_body.dig("schemas", 0)).to eq "urn:ietf:params:scim:api:messages:2.0:Error"
       end
+
+      it "returns 422 when value is " do
+        patch :patch_update, params: {
+          id: 1,
+          Operations: [
+            {
+              op: "replace",
+              path: "displayName",
+              value: "Francis"
+            }
+          ]
+        }
+
+        expect(response.status).to eq 422
+        response_body = JSON.parse(response.body)
+        expect(response_body.dig("schemas", 0)).to eq "urn:ietf:params:scim:api:messages:2.0:Error"
+      end
+
+      it "returns 422 when value is missing" do
+        patch :patch_update, params: {
+          id: 1,
+          Operations: [
+            {
+              op: "replace"
+            }
+          ]
+        }
+
+        expect(response.status).to eq 422
+        response_body = JSON.parse(response.body)
+        expect(response_body.dig("schemas", 0)).to eq "urn:ietf:params:scim:api:messages:2.0:Error"
+      end
+
+      it "returns 422 operations key is missing" do
+        patch :patch_update, params: {
+          id: 1,
+          Foobars: [
+            {
+              op: "replace"
+            }
+          ]
+        }
+
+        expect(response.status).to eq 422
+        response_body = JSON.parse(response.body)
+        expect(response_body.dig("schemas", 0)).to eq "urn:ietf:params:scim:api:messages:2.0:Error"
+      end
     end
   end