Adds PATCH methods for partial updates with Generics + Reflection.

I'm impressed with myself, honestly!

Also updates the Insomnia_requests.json, README.md and index.html.

Author: brunodrugowick

README.md

@@ -12,7 +12,9 @@ This project was bootstrapped with Spring Boot, so:
 
 ## Testing
 
-There's a [Insomnia_requests.json](src/main/resources/static/Insomnia_requests.json) file. Import it into [Insomnia](https://insomnia.rest/download/) to test all endpoints (already with examples).
+There's a [Insomnia_requests.json](src/main/resources/static/Insomnia_requests.json) file. Import it into [Insomnia](https://insomnia.rest/download/) to test all endpoints (already with examples). 
+
+You may also just... [![Run in Insomnia}](https://insomnia.rest/images/run.svg)](https://insomnia.rest/run/?label=Drugo%20AlgafoodAPI&uri=https%3A%2F%2Falgafoodapi.herokuapp.com%2FInsomnia_requests.json)
 
 You may use it against [https://algafoodapi.herokuapp.com/](https://algafoodapi.herokuapp.com/). Some endpoints you can try via browser (GET requests):
 

src/main/java/dev/drugowick/algaworks/algafoodapi/api/controller/CityController.java

@@ -1,5 +1,6 @@
 package dev.drugowick.algaworks.algafoodapi.api.controller;
 
+import dev.drugowick.algaworks.algafoodapi.api.controller.utils.ObjectMerger;
 import dev.drugowick.algaworks.algafoodapi.domain.exception.EntityBeingUsedException;
 import dev.drugowick.algaworks.algafoodapi.domain.exception.EntityNotFoundException;
 import dev.drugowick.algaworks.algafoodapi.domain.model.City;
@@ -11,6 +12,7 @@
 import org.springframework.web.bind.annotation.*;
 
 import java.util.List;
+import java.util.Map;
 
 @RestController
 @RequestMapping("cities")
@@ -24,10 +26,12 @@ public class CityController {
 
     private CityRepository cityRepository;
     private CityCrudService cityCrudService;
+    private ObjectMerger<City> objectMerger;
 
-    public CityController(CityRepository cityRepository, CityCrudService cityCrudService) {
+    public CityController(CityRepository cityRepository, CityCrudService cityCrudService, ObjectMerger<City> objectMerger) {
         this.cityRepository = cityRepository;
         this.cityCrudService = cityCrudService;
+        this.objectMerger = objectMerger;
     }
 
     @GetMapping
@@ -86,6 +90,19 @@ public ResponseEntity<?> update(@PathVariable Long id, @RequestBody City city) {
 
     }
 
+    @PatchMapping("/{id}")
+    public ResponseEntity<?> partialUpdate(@PathVariable Long id, @RequestBody Map<String, Object> cityMap) {
+        City cityToUpdate = cityRepository.get(id);
+
+        if (cityToUpdate == null) {
+            return ResponseEntity.notFound().build();
+        }
+
+        cityToUpdate = objectMerger.mergeRequestBodyToGenericObject(cityMap, cityToUpdate);
+
+        return update(id, cityToUpdate);
+    }
+
     @DeleteMapping("/{id}")
     public ResponseEntity<?> delete(@PathVariable Long id) {
         try {

src/main/java/dev/drugowick/algaworks/algafoodapi/api/controller/CuisineController.java

@@ -1,5 +1,6 @@
 package dev.drugowick.algaworks.algafoodapi.api.controller;
 
+import dev.drugowick.algaworks.algafoodapi.api.controller.utils.ObjectMerger;
 import dev.drugowick.algaworks.algafoodapi.domain.exception.EntityBeingUsedException;
 import dev.drugowick.algaworks.algafoodapi.domain.exception.EntityNotFoundException;
 import dev.drugowick.algaworks.algafoodapi.domain.model.Cuisine;
@@ -11,6 +12,7 @@
 import org.springframework.web.bind.annotation.*;
 
 import java.util.List;
+import java.util.Map;
 
 @RestController
 @RequestMapping(value = "/cuisines")
@@ -24,10 +26,12 @@ public class CuisineController {
 
 	private CuisineRepository cuisineRepository;
 	private CuisineCrudService cuisinesCrudService;
+	private ObjectMerger<Cuisine> objectMerger;
 
-	public CuisineController(CuisineRepository cuisineRepository, CuisineCrudService cuisinesCrudService) {
+	public CuisineController(CuisineRepository cuisineRepository, CuisineCrudService cuisinesCrudService, ObjectMerger<Cuisine> objectMerger) {
 		this.cuisineRepository = cuisineRepository;
 		this.cuisinesCrudService = cuisinesCrudService;
+		this.objectMerger = objectMerger;
 	}
 
 	@GetMapping
@@ -60,22 +64,35 @@ public ResponseEntity<Cuisine> get(@PathVariable Long id) {
 	@PutMapping(value = "/{id}")
 	public ResponseEntity<Cuisine> update(@PathVariable Long id, @RequestBody Cuisine cuisine) {
 		Cuisine cuisineToUpdate = cuisineRepository.get(id);
-		
+
 		if (cuisineToUpdate != null) {
 			BeanUtils.copyProperties(cuisine, cuisineToUpdate, "id");
 			cuisineToUpdate = cuisinesCrudService.update(id, cuisineToUpdate);
 			return ResponseEntity.ok(cuisineToUpdate);
 		}
-		
+
 		return ResponseEntity.notFound().build();
 	}
-	
+
+	@PatchMapping("/{id}")
+	public ResponseEntity<?> partialUpdate(@PathVariable Long id, @RequestBody Map<String, Object> cuisineMap) {
+		Cuisine cuisineToUpdate = cuisineRepository.get(id);
+
+		if (cuisineToUpdate == null) {
+			return ResponseEntity.notFound().build();
+		}
+
+		cuisineToUpdate = objectMerger.mergeRequestBodyToGenericObject(cuisineMap, cuisineToUpdate);
+
+		return update(id, cuisineToUpdate);
+	}
+
 	@DeleteMapping(value = "/{id}")
 	public ResponseEntity<Cuisine> delete(@PathVariable Long id) {
 		try {
 			cuisinesCrudService.delete(id);
 			return ResponseEntity.noContent().build();
-			
+
 		} catch (EntityBeingUsedException e) {
 			return ResponseEntity.status(HttpStatus.CONFLICT).build();
 

src/main/java/dev/drugowick/algaworks/algafoodapi/api/controller/ProvinceController.java

@@ -1,5 +1,6 @@
 package dev.drugowick.algaworks.algafoodapi.api.controller;
 
+import dev.drugowick.algaworks.algafoodapi.api.controller.utils.ObjectMerger;
 import dev.drugowick.algaworks.algafoodapi.domain.exception.EntityBeingUsedException;
 import dev.drugowick.algaworks.algafoodapi.domain.exception.EntityNotFoundException;
 import dev.drugowick.algaworks.algafoodapi.domain.model.Province;
@@ -11,6 +12,7 @@
 import org.springframework.web.bind.annotation.*;
 
 import java.util.List;
+import java.util.Map;
 
 @RestController
 @RequestMapping(value = "/provinces")
@@ -24,10 +26,12 @@ public class ProvinceController {
 
 	private ProvinceRepository provinceRepository;
 	private ProvinceCrudService provinceCrudService;
+	private ObjectMerger<Province> objectMerger;
 
-	public ProvinceController(ProvinceRepository provinceRepository, ProvinceCrudService provinceCrudService) {
+	public ProvinceController(ProvinceRepository provinceRepository, ProvinceCrudService provinceCrudService, ObjectMerger<Province> objectMerger) {
 		this.provinceRepository = provinceRepository;
 		this.provinceCrudService = provinceCrudService;
+		this.objectMerger = objectMerger;
 	}
 
 	@GetMapping
@@ -76,6 +80,19 @@ public ResponseEntity<Province> update(@PathVariable Long id, @RequestBody Provi
 		return ResponseEntity.ok(provinceToUpdate);
 	}
 
+	@PatchMapping("/{id}")
+	public ResponseEntity<?> partialUpdate(@PathVariable Long id, @RequestBody Map<String, Object> provinceMap) {
+		Province provinceToUpdate = provinceRepository.get(id);
+
+		if (provinceToUpdate == null) {
+			return ResponseEntity.notFound().build();
+		}
+
+		provinceToUpdate = objectMerger.mergeRequestBodyToGenericObject(provinceMap, provinceToUpdate);
+
+		return update(id, provinceToUpdate);
+	}
+
 	@DeleteMapping(value = "/{id}")
 	public ResponseEntity<?> delete(@PathVariable Long id) {
 		try {

src/main/java/dev/drugowick/algaworks/algafoodapi/api/controller/RestaurantController.java

@@ -1,5 +1,6 @@
 package dev.drugowick.algaworks.algafoodapi.api.controller;
 
+import dev.drugowick.algaworks.algafoodapi.api.controller.utils.ObjectMerger;
 import dev.drugowick.algaworks.algafoodapi.domain.exception.EntityBeingUsedException;
 import dev.drugowick.algaworks.algafoodapi.domain.exception.EntityNotFoundException;
 import dev.drugowick.algaworks.algafoodapi.domain.model.Restaurant;
@@ -10,15 +11,18 @@
 import org.springframework.web.bind.annotation.*;
 
 import java.util.List;
+import java.util.Map;
 
 @RestController
 @RequestMapping("/restaurants")
 public class RestaurantController {
-	
+
 	private RestaurantCrudService restaurantCrudService;
+	private ObjectMerger<Restaurant> objectMerger;
 
-	public RestaurantController(RestaurantCrudService restaurantCrudService) {
+	public RestaurantController(RestaurantCrudService restaurantCrudService, ObjectMerger<Restaurant> objectMerger) {
 		this.restaurantCrudService = restaurantCrudService;
+		this.objectMerger = objectMerger;
 	}
 
 	@GetMapping
@@ -73,6 +77,19 @@ public ResponseEntity<?> update(@PathVariable Long id, @RequestBody Restaurant r
 		}
 	}
 
+	@PatchMapping("/{id}")
+	public ResponseEntity<?> partialUpdate(@PathVariable Long id, @RequestBody Map<String, Object> restaurantMap) {
+		Restaurant restaurantToUpdate = restaurantCrudService.read(id);
+
+		if (restaurantToUpdate == null) {
+			return ResponseEntity.notFound().build();
+		}
+
+		restaurantToUpdate = objectMerger.mergeRequestBodyToGenericObject(restaurantMap, restaurantToUpdate);
+
+		return update(id, restaurantToUpdate);
+	}
+
 	@DeleteMapping("/{id}")
 	public ResponseEntity<?> delete(@PathVariable Long id) {
 		try {

src/main/java/dev/drugowick/algaworks/algafoodapi/api/controller/utils/ObjectMerger.java

@@ -0,0 +1,40 @@
+package dev.drugowick.algaworks.algafoodapi.api.controller.utils;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.springframework.util.ReflectionUtils;
+
+import java.lang.reflect.Field;
+import java.util.Map;
+
+/**
+ * Helper method to merge the request body (a Map<String, Object>) to an Object to be updated via a Patch HTTP request.
+ * <p>
+ * Uses ReflectionUtils from Spring Framework to set values to the Object.
+ *
+ * @param <T>
+ */
+public class ObjectMerger<T> {
+
+    private ObjectMapper objectMapper;
+    private Class<T> type;
+
+    public ObjectMerger(Class<T> type) {
+        this.objectMapper = new ObjectMapper();
+        this.type = type;
+    }
+
+    public T mergeRequestBodyToGenericObject(Map<String, Object> objectMap, T objectToUpdate) {
+        T newObject = objectMapper.convertValue(objectMap, type);
+
+        objectMap.forEach((fieldProp, valueProp) -> {
+            Field field = ReflectionUtils.findField(type, fieldProp);
+            field.setAccessible(true);
+
+            Object newValue = ReflectionUtils.getField(field, newObject);
+
+            ReflectionUtils.setField(field, objectToUpdate, newValue);
+        });
+
+        return objectToUpdate;
+    }
+}

src/main/java/dev/drugowick/algaworks/algafoodapi/config/ObjectMergerConfig.java

@@ -0,0 +1,39 @@
+package dev.drugowick.algaworks.algafoodapi.config;
+
+import dev.drugowick.algaworks.algafoodapi.api.controller.utils.ObjectMerger;
+import dev.drugowick.algaworks.algafoodapi.domain.model.City;
+import dev.drugowick.algaworks.algafoodapi.domain.model.Cuisine;
+import dev.drugowick.algaworks.algafoodapi.domain.model.Province;
+import dev.drugowick.algaworks.algafoodapi.domain.model.Restaurant;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * Confiures the ObjectMerger objects to instantiate as Beans.
+ * <p>
+ * These Beans will be used on Controllers for object transformation from Map<String, Object> to <T> object.
+ * This is especially useful for PATCH HTTP requests.
+ */
+@Configuration
+public class ObjectMergerConfig {
+
+    @Bean
+    public ObjectMerger<Restaurant> restaurantObjectMerger() {
+        return new ObjectMerger<>(Restaurant.class);
+    }
+
+    @Bean
+    public ObjectMerger<Cuisine> cuisineObjectMerger() {
+        return new ObjectMerger<>(Cuisine.class);
+    }
+
+    @Bean
+    public ObjectMerger<City> cityObjectMerger() {
+        return new ObjectMerger<>(City.class);
+    }
+
+    @Bean
+    public ObjectMerger<Province> provinceObjectMerger() {
+        return new ObjectMerger<>(Province.class);
+    }
+}