Return all CanDecide errors simultaneously (#421)

* refactor validate

* test: adjust to split function

* feat: add mergeResults

* test: mergeResults

* refactor: wording

* refactor: simplify recursion

---------

Co-authored-by: Julian König <julian.koenig@js-soft.com>

Author: Milena-Czierlinski

packages/consumption/src/modules/common/index.ts

@@ -1,2 +1,3 @@
 export * from "./flattenObject";
+export * from "./mergeResults";
 export * from "./ValidationResult";

packages/consumption/src/modules/common/mergeResults.ts

@@ -0,0 +1,10 @@
+import { ValidationResult } from "./ValidationResult";
+
+export function mergeResults(result1: ValidationResult, result2: ValidationResult): ValidationResult {
+    if (result1.items.length !== result2.items.length) throw new Error("The dimensions of the ValidationResults do not match.");
+
+    if (result1.items.length === 0) return result1.isError() ? result1 : result2;
+
+    const mergedValidationResults = result1.items.map((item, index) => mergeResults(item, result2.items[index]));
+    return ValidationResult.fromItems(mergedValidationResults);
+}

packages/consumption/src/modules/requests/incoming/DecideRequestParametersValidator.ts

@@ -8,7 +8,7 @@ import { DecideRequestItemParametersJSON, isDecideRequestItemParametersJSON } fr
 import { InternalDecideRequestParametersJSON } from "./decide/InternalDecideRequestParameters";
 
 export class DecideRequestParametersValidator {
-    public validate(params: InternalDecideRequestParametersJSON, request: LocalRequest): ValidationResult {
+    public validateRequest(params: InternalDecideRequestParametersJSON, request: LocalRequest): ValidationResult {
         if (!request.id.equals(CoreId.from(params.requestId))) {
             throw new Error("The response is invalid because the id of the Request does not match the id of the Response.");
         }
@@ -19,6 +19,10 @@ export class DecideRequestParametersValidator {
             );
         }
 
+        return ValidationResult.success();
+    }
+
+    public validateItems(params: InternalDecideRequestParametersJSON, request: LocalRequest): ValidationResult {
         const validationResults = request.content.items.map((requestItem, index) => this.checkItemOrGroup(requestItem, params.items[index], params.accept));
         return ValidationResult.fromItems(validationResults);
     }

packages/consumption/src/modules/requests/incoming/IncomingRequestsController.ts

@@ -9,6 +9,7 @@ import { ConsumptionControllerName } from "../../../consumption/ConsumptionContr
 import { ConsumptionCoreErrors } from "../../../consumption/ConsumptionCoreErrors";
 import { ConsumptionError } from "../../../consumption/ConsumptionError";
 import { ConsumptionIds } from "../../../consumption/ConsumptionIds";
+import { mergeResults } from "../../common";
 import { ValidationResult } from "../../common/ValidationResult";
 import { IncomingRequestReceivedEvent, IncomingRequestStatusChangedEvent } from "../events";
 import { RequestItemProcessorRegistry } from "../itemProcessors/RequestItemProcessorRegistry";
@@ -214,12 +215,22 @@ export class IncomingRequestsController extends ConsumptionBaseController {
             );
         }
 
-        const validationResult = this.decideRequestParamsValidator.validate(params, request);
-        if (validationResult.isError()) return validationResult;
+        const validateRequestResult = this.decideRequestParamsValidator.validateRequest(params, request);
+        if (validateRequestResult.isError()) return validateRequestResult;
 
-        const itemResults = await this.canDecideItems(params.items, request.content.items, request);
+        const validateItemsResult = this.decideRequestParamsValidator.validateItems(params, request);
 
-        return ValidationResult.fromItems(itemResults);
+        const canDecideItemsResults = await this.canDecideItems(params.items, request.content.items, request);
+        const canDecideItemsResult = ValidationResult.fromItems(canDecideItemsResults);
+
+        try {
+            return mergeResults(validateItemsResult, canDecideItemsResult);
+        } catch (_) {
+            this._log.error(
+                `Merging '${JSON.stringify(validateItemsResult)}' and '${JSON.stringify(canDecideItemsResult)}' was not possible because their dimensions don't match.`
+            );
+            return validateItemsResult.isError() ? validateItemsResult : canDecideItemsResult;
+        }
     }
 
     private async canDecideGroup(params: DecideRequestItemGroupParametersJSON, requestItemGroup: RequestItemGroup, request: LocalRequest) {