add createOrUpdate for recipes

src/handlers/RecipeHandler.ts

@@ -5,6 +5,7 @@ import { NotFoundError, ValidationError } from "../errors/httpErrors.js";
 import { RecipeInstructionStepDto } from "../dtos/RecipeInstructionStepDto.js";
 import { RecipeIngredientGroupDto } from "../dtos/RecipeIngredientGroupDto.js";
 import { RecipeIngredientDto } from "../dtos/RecipeIngredientDto.js";
+import { RecipeEntity } from "../entities/RecipeEntity.js";
 
 /**
  * Controls all recipe specific actions
@@ -28,6 +29,37 @@ export class RecipeHandler {
         const recipeDto = this.mapper.toDto(recipeEntity);
         return recipeDto;
     }
+
+    /**
+     * Save or update recipe depending on whether the DTO contains an ID
+     * @param dto recipe data
+     * @returns Recipe as saved in the database
+     */
+    async createOrUpdateRecipe(dto: RecipeDto){
+        if (!this.isRecipeDtoValid(dto)) {
+            throw new ValidationError("recipe data is not valid!")
+        }
+        var savedEntity: RecipeEntity;
+        const recipeId = dto.id
+        if(recipeId === undefined){
+            // create new recipe
+            const recipeEntity = this.mapper.toEntity(dto)
+            savedEntity = await this.recipeRepository.create(recipeEntity);
+            throw new ValidationError("Trying to update recipe without ID!")
+        } else {
+            // save existing Recipe
+            // First: Load current version of recipe from database
+            const recipeEntity = await this.recipeRepository.findById(recipeId);
+            if(!recipeEntity){
+                throw new ValidationError("No recipe with ID " + recipeId + " found in database!")
+            }
+            // merge changes into entity
+            this.mapper.mergeDtoIntoEntity(dto, recipeEntity);
+            // persist changes
+            savedEntity = await this.recipeRepository.update(recipeEntity);
+        }
+        return this.mapper.toDto(savedEntity);
+    }
     /**
      * Update recipe data
      * @param RecipeDto containing the entire updated recipe