add list mappers

src/api/endpoints/CompactRecipeRestResource.ts

@@ -14,22 +14,13 @@ export const compactRecipeBasicRoute = "/compact-recipe"
 const router = Router();
 
 // Inject repo + mapper here
-const compactRecipeHandler = new CompactRecipeHandler(new RecipeRepository(), new CompactRecipeDtoEntityMapper());
-/**
- * Load header data of all recipes
- * Responds with a list of CompactRecipeDtos
- */
-router.get(
-  "/",
-  asyncHandler(async (req, res) => {  
-    // extract search string from query parameters, convert to lower case for case insensitive search
-    const searchString : string  = req.query.search ? req.query.search.toString().toLowerCase() : "";
-    console.log("Searching for recipes with title containing", searchString)
-    const response = await compactRecipeHandler.getMatchingRecipes(searchString);
-    res.status(HttpStatusCode.OK).json(response);
-  })
-);
+const recipeRepository = new RecipeRepository();
+const compactRecipeDtoEntityMapper = new CompactRecipeDtoEntityMapper();
+const compactRecipeHandler = new CompactRecipeHandler(recipeRepository, compactRecipeDtoEntityMapper);
 
+/**
+ * Load recipe header data of all recipes matching the filter. If no filter is given, all recipes are returned.
+ */
 router.get(
     "/list-by-filter",
     asyncHandler(async (req , res) => {

src/handlers/CompactRecipeHandler.ts

@@ -2,8 +2,8 @@ import { CompactRecipeDto } from "../api/dtos/CompactRecipeDto.js";
 import { RecipeEntity } from "../entities/RecipeEntity.js";
 import { CompactRecipeDtoEntityMapper } from "../mappers/CompactRecipeDtoEntityMapper.js";
 import { RecipeRepository } from "../repositories/RecipeRepository.js";
-import {CompactRecipeFilterRequest} from "../api/dtos/CompactRecipeFilterRequest.js";
-import {CompactRecipeFilterResponse} from "../api/dtos/CompactRecipeFilterResponse.js";
+import { CompactRecipeFilterRequest } from "../api/dtos/CompactRecipeFilterRequest.js";
+import { CompactRecipeFilterResponse } from "../api/dtos/CompactRecipeFilterResponse.js";
 
 /**
  * Responsible for loading recipe header data
@@ -16,46 +16,25 @@ export class CompactRecipeHandler {
 
     /**
      * Load list of all recipes
-     * @returns List of all recipes
+     * @returns List of all recipes as CompactRecipeDtos
      */
-    async getAllCompactRecipes() {
+    async getAllCompactRecipes(): Promise<CompactRecipeDto[]> {
         const recipeEntities: RecipeEntity[] = await this.repository.findAll();
-        let recipeDtos: CompactRecipeDto[] = [];
-        recipeEntities.forEach(recipeEntity => {
-            recipeDtos.push(this.mapper.toDto(recipeEntity));
-        });
-        return recipeDtos;
+        return this.mapper.mapEntityListToDtoList(recipeEntities);
     }
 
     /**
-     * Get all recipes matching search
-     * 
-     * Recipe title must contain type string
-     * @todo Full text search??
-
+     * Get all recipes matching the given filter criteria.
+     * @param request Filter request containing optional search string and tag ID list
+     * @returns CompactRecipeFilterResponse containing the matching recipes
      */
-    async getMatchingRecipes(searchString : string){
-        if(!searchString || searchString.length===0){
-            // get all 
-            return this.getAllCompactRecipes();
-        } else {
-            const tagIdList : string[] = [];
-            return this.repository.findCompactRecipeByFilter(searchString, tagIdList);
-        }
-    }
-
-    async getRecipesByFilter(request: CompactRecipeFilterRequest) : Promise<CompactRecipeFilterResponse> {
-        const searchString = request.searchString;
-        const tagIdList = request.tagIdList;
-        var recipeEntities : RecipeEntity[] = await this.repository.findCompactRecipeByFilter(searchString, tagIdList);
+    async getRecipesByFilter(request: CompactRecipeFilterRequest): Promise<CompactRecipeFilterResponse> {
+        const recipeEntities: RecipeEntity[] = await this.repository.findCompactRecipeByFilter(
+            request.searchString,
+            request.tagIdList
+        );
         const response = new CompactRecipeFilterResponse();
-        // @todo move list mapping to mapper
-        let recipeDtos: CompactRecipeDto[] = [];
-        // Add mapper function to map the result list.
-        recipeEntities.forEach(recipeEntity => {
-            recipeDtos.push(this.mapper.toDto(recipeEntity));
-        });
-        response.compactRecipeList = recipeDtos;
+        response.compactRecipeList = this.mapper.mapEntityListToDtoList(recipeEntities);
         return response;
     }
 }

src/mappers/AbstractDtoEntityMapper.ts

@@ -2,80 +2,102 @@ import { AbstractDto } from "../api/dtos/AbstractDto.js";
 import { AbstractEntity } from "../entities/AbstractEntity.js";
 
 export abstract class AbstractDtoEntityMapper<
-  E extends AbstractEntity,
-  D extends AbstractDto
+    E extends AbstractEntity,
+    D extends AbstractDto
 > {
-  /**
-   * Map base entity fields (id, createdAt, updatedAt) to DTO.
-   */
-  protected mapBaseEntityToDto(entity: E, dto: D): D {
-    dto.id = entity.id;
-    dto.createdAt = entity.createDate;
-    dto.updatedAt = entity.updateDate;
-    return dto;
-  }
-
-  /**
-   * Map base DTO fields to entity.
-   */
-  protected mapBaseDtoToEntity(dto: D, entity: E): E {
-    entity.id = dto.id;
-    entity.createDate = dto.createdAt;
-    entity.updateDate = dto.updatedAt;
-    return entity;
-  }
-
-  /**
-   * Merge entity list  with changes contained in DTO list
-   * @param dtos List of dtos
-   * @param entities List of entities
-   * @returns Merged list
-   * 
-   * elements no longer contained in the dto list will be removed from the entity list
-   * new elements will be mapped to entity and added to the entity list
-   * existing elements will be updated
-   */
-  mergeDtoListIntoEntityList(dtos: D[], entities: E[]) : E[]{
-    const updatedEntities: E[] = [];
-    const existingMap = new Map(entities?.map(e => [e.id, e]) ?? []);
-
-    for (const dto of dtos) {
-      if (dto.id && existingMap.has(dto.id)) {
-        // update existing
-        const entity = existingMap.get(dto.id)!;
-        updatedEntities.push(this.mergeDtoIntoEntity(dto, entity));
-      } else {
-        // create new
-        const newEntity = this.createNewEntity();
-        updatedEntities.push(this.mergeDtoIntoEntity(dto, newEntity));
-      }
+    /**
+     * Map base entity fields (id, createdAt, updatedAt) to DTO.
+     */
+    protected mapBaseEntityToDto(entity: E, dto: D): D {
+        dto.id = entity.id;
+        dto.createdAt = entity.createDate;
+        dto.updatedAt = entity.updateDate;
+        return dto;
     }
 
-    return updatedEntities;
-  }
+    /**
+     * Map base DTO fields to entity.
+     */
+    protected mapBaseDtoToEntity(dto: D, entity: E): E {
+        entity.id = dto.id;
+        entity.createDate = dto.createdAt;
+        entity.updateDate = dto.updatedAt;
+        return entity;
+    }
 
-  // Abstract methods to be implemented by subclasses
-  /**
-   * Maps an entity to DTO
-   * @param entity Entity that is mapped to DTO
-   */
-  abstract toDto(entity: E): D;
-  /**
-   * Maps a DTO to entity
-   * @param dto DTO to map to entity
-   */
-  abstract toEntity(dto: D): E;
-  /**
-   * Merge changes in DTO into entity
-   * @param dto Dto containing changes
-   * @param entity existing entity 
-   * 
-   * Used for merging user changes (DTO) into the existing entity (database).
-   */
-  abstract mergeDtoIntoEntity(dto: D, entity: E): E;
-  /**
-   * Defines how to create a new entity. Required by mergeDtoListIntoEntityList
-   * to add new elements to the list
-   */
-  abstract createNewEntity() : E;
-}
+    /**
+     * Maps a list of entities to a list of DTOs.
+     * @param entities List of entities to map
+     * @returns List of DTOs
+     */
+    mapEntityListToDtoList(entities: E[]): D[] {
+        return entities.map(entity => this.toDto(entity));
+    }
+
+    /**
+     * Maps a list of DTOs to a list of entities.
+     * @param dtos List of DTOs to map
+     * @returns List of entities
+     */
+    mapDtoListToEntityList(dtos: D[]): E[] {
+        return dtos.map(dto => this.toEntity(dto));
+    }
+
+    /**
+     * Merge entity list with changes contained in DTO list.
+     * @param dtos List of dtos
+     * @param entities List of entities
+     * @returns Merged list
+     *
+     * Elements no longer contained in the dto list will be removed from the entity list.
+     * New elements will be mapped to entity and added to the entity list.
+     * Existing elements will be updated.
+     */
+    mergeDtoListIntoEntityList(dtos: D[], entities: E[]): E[] {
+        const updatedEntities: E[] = [];
+        const existingMap = new Map(entities?.map(e => [e.id, e]) ?? []);
+
+        for (const dto of dtos) {
+            if (dto.id && existingMap.has(dto.id)) {
+                // update existing
+                const entity = existingMap.get(dto.id)!;
+                updatedEntities.push(this.mergeDtoIntoEntity(dto, entity));
+            } else {
+                // create new
+                const newEntity = this.createNewEntity();
+                updatedEntities.push(this.mergeDtoIntoEntity(dto, newEntity));
+            }
+        }
+
+        return updatedEntities;
+    }
+
+    // Abstract methods to be implemented by subclasses
+
+    /**
+     * Maps an entity to DTO.
+     * @param entity Entity that is mapped to DTO
+     */
+    abstract toDto(entity: E): D;
+
+    /**
+     * Maps a DTO to entity.
+     * @param dto DTO to map to entity
+     */
+    abstract toEntity(dto: D): E;
+
+    /**
+     * Merge changes in DTO into entity.
+     * @param dto Dto containing changes
+     * @param entity existing entity
+     *
+     * Used for merging user changes (DTO) into the existing entity (database).
+     */
+    abstract mergeDtoIntoEntity(dto: D, entity: E): E;
+
+    /**
+     * Defines how to create a new entity. Required by mergeDtoListIntoEntityList
+     * to add new elements to the list.
+     */
+    abstract createNewEntity(): E;
+}

src/mappers/CompactRecipeDtoEntityMapper.ts

@@ -2,7 +2,10 @@ import { CompactRecipeDto } from "../api/dtos/CompactRecipeDto.js";
 import { RecipeEntity } from "../entities/RecipeEntity.js";
 import { AbstractDtoEntityMapper } from "./AbstractDtoEntityMapper.js";
 
-export class CompactRecipeDtoEntityMapper extends AbstractDtoEntityMapper<RecipeEntity,CompactRecipeDto>{
+export class CompactRecipeDtoEntityMapper extends AbstractDtoEntityMapper<RecipeEntity, CompactRecipeDto> {
+    constructor() {
+        super();
+    }
 
     toDto(entity: RecipeEntity): CompactRecipeDto {
         const dto = new CompactRecipeDto();
@@ -13,20 +16,23 @@ export class CompactRecipeDtoEntityMapper extends AbstractDtoEntityMapper<Recipe
         return dto;
     }
 
-  toEntity(dto: CompactRecipeDto): RecipeEntity {
-    throw new Error("Mapping CompactRecipeDto to RecipeEntity is not allowed!");
-  }
+    toEntity(dto: CompactRecipeDto): RecipeEntity {
+        throw new Error("Mapping CompactRecipeDto to RecipeEntity is not allowed!");
+    }
 
-  createNewEntity() : RecipeEntity {
-    throw new Error("Mapping CompactRecipeDto to RecipeEntity is not allowed!");
-  }
+    createNewEntity(): RecipeEntity {
+        throw new Error("Mapping CompactRecipeDto to RecipeEntity is not allowed!");
+    }
 
-  mergeDtoIntoEntity(dto: CompactRecipeDto, entity: RecipeEntity): RecipeEntity {
-    throw new Error("Mapping CompactRecipeDto to RecipeEntity is not allowed!");
-  }
+    mergeDtoIntoEntity(dto: CompactRecipeDto, entity: RecipeEntity): RecipeEntity {
+        throw new Error("Mapping CompactRecipeDto to RecipeEntity is not allowed!");
+    }
 
-  mergeDtoListIntoEntityList(dtos: CompactRecipeDto[], entities: RecipeEntity[]) : RecipeEntity[]{
-    throw new Error("Mapping CompactRecipeDto to RecipeEntity is not allowed!");
-  }
+    mergeDtoListIntoEntityList(dtos: CompactRecipeDto[], entities: RecipeEntity[]): RecipeEntity[] {
+        throw new Error("Mapping CompactRecipeDto to RecipeEntity is not allowed!");
+    }
 
+    mapDtoListToEntityList(dtos: CompactRecipeDto[]): RecipeEntity[] {
+        throw new Error("Mapping CompactRecipeDto to RecipeEntity is not allowed!");
+    }
 }

src/mappers/RecipeDtoEntityMapper.ts

@@ -6,7 +6,6 @@ import { AbstractDtoEntityMapper } from "./AbstractDtoEntityMapper.js";
 import { RecipeIngredientGroupDtoEntityMapper } from "./RecipeIngredientGroupDtoEntityMapper.js";
 import { RecipeInstructionStepDtoEntityMapper } from "./RecipeInstructionStepDtoEntityMapper.js";
 import { TagDtoEntityMapper } from "./TagDtoEntityMapper.js";
-import {TagEntity} from "../entities/TagEntity.js";
 
 export class RecipeDtoEntityMapper extends AbstractDtoEntityMapper<RecipeEntity, RecipeDto> {
     constructor(
@@ -40,9 +39,7 @@ export class RecipeDtoEntityMapper extends AbstractDtoEntityMapper<RecipeEntity,
         });
 
         // map tags
-        dto.tagList = (entity.tagList ?? []).map((tagEntity) =>
-            this.tagMapper.toDto(tagEntity)
-        );
+        dto.tagList = this.tagMapper.mapEntityListToDtoList(entity.tagList ?? []);
 
         return dto;
     }
@@ -90,9 +87,7 @@ export class RecipeDtoEntityMapper extends AbstractDtoEntityMapper<RecipeEntity,
         });
 
         // map tags
-        entity.tagList = (dto.tagList ?? []).map((tagDto) =>
-            this.tagMapper.toEntity(tagDto)
-        );
+        entity.tagList = this.tagMapper.mapDtoListToEntityList(dto.tagList ?? []);
 
         return entity;
     }
@@ -115,15 +110,12 @@ export class RecipeDtoEntityMapper extends AbstractDtoEntityMapper<RecipeEntity,
         );
 
         // --- Tags ---
-        /* Only build a stub here instead of using the mapper to avoid causing a cascade on the tag table while
-         * updating the join table correctly. For this purpose, the ORM only needs to know the tag ID in order to
-         * signal that we are dealing with an existing tag.
-         */
-        entity.tagList = (dto.tagList ?? []).map((tagDto) => {
-            const stub = new TagEntity();
-            stub.id = tagDto.id;
-            return stub;
-        });
+        // Tags are looked up by ID and replaced wholesale: the recipe holds
+        // references to existing tag entities, so we map each DTO to its entity
+        // form and let TypeORM sync the join table on save.
+        entity.tagList = (dto.tagList ?? []).map((tagDto) =>
+            this.tagMapper.toEntity(tagDto)
+        );
 
         return entity;
     }