Refactor codebase and Rename all abbreviations + Add swagger

docker-compose.yaml

@@ -10,7 +10,7 @@ services:
     ports:
       - "5432:5432"
     volumes:
-      - ./docker-entrypoint:/docker-entrypoint-initdb.d
+      - ./config/docker-entrypoint:/docker-entrypoint-initdb.d
   zookeeper:
     image: confluentinc/cp-zookeeper:latest
     container_name: spring-batch-zookeeper-demo

pom.xml

@@ -44,6 +44,12 @@
             <artifactId>spring-boot-starter-aop</artifactId>
         </dependency>
 
+        <dependency>
+            <groupId>org.springdoc</groupId>
+            <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
+            <version>2.5.0</version>
+        </dependency>
+
         <dependency>
             <groupId>org.postgresql</groupId>
             <artifactId>postgresql</artifactId>

src/main/java/com/ittovative/batchprocessing/BatchProcessingApplication.java

@@ -1,14 +1,43 @@
 package com.ittovative.batchprocessing;
 
 
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.CONTACT_EMAIL;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.CONTACT_NAME;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.CONTACT_URL;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.DESCRIPTION;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.DEVELOPMENT_SERVER_DESCRIPTION;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.DEVELOPMENT_SERVER_URL;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.TITLE;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.VERSION;
+
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 
+import io.swagger.v3.oas.annotations.OpenAPIDefinition;
+import io.swagger.v3.oas.annotations.info.Contact;
+import io.swagger.v3.oas.annotations.info.Info;
+import io.swagger.v3.oas.annotations.servers.Server;
+
 /**
  * The type Batch processing application.
  */
 @SpringBootApplication
 @SuppressWarnings("checkstyle:HideUtilityClassConstructor")
+@OpenAPIDefinition(
+        info = @Info(
+                title = TITLE,
+                description = DESCRIPTION,
+                contact = @Contact(
+                        email = CONTACT_EMAIL,
+                        name = CONTACT_NAME,
+                        url = CONTACT_URL
+                ),
+                version = VERSION
+        ),
+        servers = {
+                @Server(url = DEVELOPMENT_SERVER_URL, description = DEVELOPMENT_SERVER_DESCRIPTION)
+        }
+)
 public class BatchProcessingApplication {
 
     /**
@@ -20,16 +49,4 @@ public static void main(String... args) {
         SpringApplication.run(BatchProcessingApplication.class, args);
     }
 
-    // uncomment to insert dummy orders to kafka at the app's startup
-
-    /*@Bean
-    public CommandLineRunner commandLineRunner(KafkaTemplate<Long, Order> kafkaTemplate) {
-        return args -> {
-            for (int i = 0; i < 500; i++) {
-                Order person = new Order(i,"order#"+i,"dummy description");
-                kafkaTemplate.send("orders",person);
-            }
-        };
-    }*/
-
 }

src/main/java/com/ittovative/batchprocessing/config/APIResponseConstant.java

@@ -0,0 +1,9 @@
+package com.ittovative.batchprocessing.config;
+
+public final class APIResponseConstant {
+    public static final String ADD_ORDER_SUCCESSFUL_MESSAGE = "Order added successfully!";
+    public static final String BATCH_SUCCESS_MESSAGE = "Batch ended successfully!";
+
+    private APIResponseConstant() {
+    }
+}

src/main/java/com/ittovative/batchprocessing/config/BatchConfig.java

@@ -1,7 +1,9 @@
 package com.ittovative.batchprocessing.config;
 
+import static com.ittovative.batchprocessing.constant.AppConstant.KAFKA_TOPIC;
+
+import com.ittovative.batchprocessing.constant.AppConstant;
 import com.ittovative.batchprocessing.model.Order;
-import com.ittovative.batchprocessing.util.AppConstants;
 import org.springframework.batch.core.Job;
 import org.springframework.batch.core.Step;
 import org.springframework.batch.core.job.builder.JobBuilder;
@@ -89,7 +91,7 @@ public Step databaseProcessOrder(JobRepository jobRepository,
                                      DataSource dataSource,
                                      PagingQueryProvider pagingQueryProvider) {
         return new StepBuilder("database-order-processing-step", jobRepository)
-                .<Order, Order>chunk(AppConstants.CHUNK_SIZE, platformTransactionManager)
+                .<Order, Order>chunk(AppConstant.CHUNK_SIZE, platformTransactionManager)
                 .reader(jdbcOrderItemReader(dataSource, pagingQueryProvider))
                 .processor(itemProcessor())
                 .writer(flatFileItemWriter())
@@ -109,7 +111,7 @@ public Step kafkaProcessOrder(JobRepository jobRepository,
                                   PlatformTransactionManager platformTransactionManager,
                                   DefaultKafkaConsumerFactory<Long, Order> defaultKafkaConsumerFactory) {
         return new StepBuilder("kafka-order-processing-step", jobRepository)
-                .<Order, Order>chunk(AppConstants.CHUNK_SIZE, platformTransactionManager)
+                .<Order, Order>chunk(AppConstant.CHUNK_SIZE, platformTransactionManager)
                 .reader(kafkaOrderItemReader(defaultKafkaConsumerFactory))
                 .processor(itemProcessor())
                 .writer(flatFileItemWriter())
@@ -131,7 +133,7 @@ public JdbcPagingItemReader<Order> jdbcOrderItemReader(DataSource dataSource,
                 .name("jdbc-item-reader")
                 .dataSource(dataSource)
                 .queryProvider(pagingQueryProvider)
-                .pageSize(AppConstants.PAGE_SIZE)
+                .pageSize(AppConstant.PAGE_SIZE)
                 .rowMapper((resultSet, rowNum) -> {
                     int id = resultSet.getInt("id");
                     String name = resultSet.getString("name");
@@ -173,7 +175,7 @@ public KafkaItemReader<Long, Order> kafkaOrderItemReader(
                 .name("orders-kafka-item-reader")
                 .partitions(0)
                 .saveState(true)
-                .topic("orders")
+                .topic(KAFKA_TOPIC)
                 .consumerProperties(kafkaConsumerProperties)
                 .partitionOffsets(new HashMap<>())
                 .build();
@@ -187,8 +189,8 @@ public KafkaItemReader<Long, Order> kafkaOrderItemReader(
     @Bean
     public ItemProcessor<Order, Order> itemProcessor() {
         return item -> {
-            logger.info("Order: {" + item.getName().toLowerCase(Locale.ROOT) + "} is being processed!");
-            Thread.sleep(AppConstants.THREAD_SLEEP_TIME_MS); // simulating real processing time
+            logger.info("Order: {" + item.name().toLowerCase(Locale.ROOT) + "} is being processed!");
+            Thread.sleep(AppConstant.THREAD_SLEEP_TIME_MS); // simulating real processing time
             return item;
         };
     }

src/main/java/com/ittovative/batchprocessing/constant/AppConstant.java

@@ -0,0 +1,12 @@
+package com.ittovative.batchprocessing.constant;
+
+public final class AppConstant {
+    public static final int THREAD_SLEEP_TIME_MS = 500;
+    public static final int CHUNK_SIZE = 5;
+    public static final int PAGE_SIZE = 5;
+
+    public static final String KAFKA_TOPIC = "dummy-orders";
+
+    private AppConstant() {
+    }
+}

src/main/java/com/ittovative/batchprocessing/constant/SwaggerConstant.java

@@ -0,0 +1,56 @@
+package com.ittovative.batchprocessing.constant;
+
+public class SwaggerConstant {
+    public static final String TITLE = "Demo Batch Processing";
+    public static final String VERSION = "0.0.1";
+    public static final String DESCRIPTION = "Demo of using spring batch";
+    public static final String CONTACT_NAME = "Mohanad Khaled";
+    public static final String CONTACT_EMAIL = "mohanadkhaled87@gmail.com";
+    public static final String CONTACT_URL = "https://github.com/orgs/ittovate/";
+    public static final String DEVELOPMENT_SERVER_URL = "http://localhost:8080";
+    public static final String DEVELOPMENT_SERVER_DESCRIPTION = "Development Server";
+
+    //================================================= Add Order =================================================//
+
+    public static final String ADD_ORDER_KAFKA_SUMMARY = "Add new order to kafka";
+    public static final String ADD_ORDER_DB_SUMMARY = "Add new order to db";
+
+    public static final String ADD_ORDER_DESCRIPTION = "Add a new order with the " +
+            "specified name and description to the application for processing.";
+    public static final String ADD_ORDER_CREATED = "201";
+    public static final String ADD_ORDER_OK_RESPONSE_DESCRIPTION = "When order is sent successfully";
+    public static final String ADD_ORDER_REQUEST_EXAMPLE = """
+            {
+              "name": "string",
+              "description": "string"
+            }
+            """;
+    public static final String ADD_ORDER_OK_RESPONSE_EXAMPLE = """
+            {
+              "statusCode": 201,
+              "message": "Order sent successfully!",
+              "body": null
+            }
+
+            """;
+    //================================================= Start Batch =================================================//
+    private static final String START_BATCH_SUMMARY = "Start batch processing";
+
+    public static final String START_BATCH_SUMMARY_KAFKA = START_BATCH_SUMMARY + " from kafka";
+    public static final String START_BATCH_SUMMARY_DB = START_BATCH_SUMMARY + " from db";
+
+    public static final String START_BATCH_DESCRIPTION = "Starts batch processing from the beginning unless there was a " +
+            "previous failuer that was handled manually in spring batch's database , in this case it will restart after the " +
+            "last successful commit successful.";
+    public static final String START_BATCH_OK = "200";
+    public static final String START_BATCH_SUCCESFUL_DESCRIPTION = "When batch is processed successfully";
+
+    public static final String START_BATCH_OK_RESPONSE_EXAMPLE = """
+            {
+              "statusCode": 200,
+              "message": "Batch ended successfully!!",
+              "body": null
+            }
+
+            """;
+}

src/main/java/com/ittovative/batchprocessing/controller/OrderController.java

@@ -1,12 +1,31 @@
 package com.ittovative.batchprocessing.controller;
 
-import com.ittovative.batchprocessing.dto.OrderDto;
+import static com.ittovative.batchprocessing.config.APIResponseConstant.ADD_ORDER_SUCCESSFUL_MESSAGE;
+import static com.ittovative.batchprocessing.config.APIResponseConstant.BATCH_SUCCESS_MESSAGE;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.ADD_ORDER_DB_SUMMARY;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.ADD_ORDER_DESCRIPTION;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.ADD_ORDER_OK_RESPONSE_EXAMPLE;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.ADD_ORDER_REQUEST_EXAMPLE;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.ADD_ORDER_KAFKA_SUMMARY;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.START_BATCH_DESCRIPTION;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.START_BATCH_OK;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.START_BATCH_OK_RESPONSE_EXAMPLE;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.START_BATCH_SUMMARY_DB;
+import static com.ittovative.batchprocessing.constant.SwaggerConstant.START_BATCH_SUMMARY_KAFKA;
+import static org.springframework.http.HttpStatus.CREATED;
+
 import com.ittovative.batchprocessing.model.Order;
 import com.ittovative.batchprocessing.service.OrderService;
-import com.ittovative.batchprocessing.util.ApiResponse;
-import com.ittovative.batchprocessing.util.BatchReadType;
+import com.ittovative.batchprocessing.util.APIResponse;
+import com.ittovative.batchprocessing.enums.BatchReadType;
+import com.ittovative.batchprocessing.util.ResponseUtil;
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.media.Content;
+import io.swagger.v3.oas.annotations.media.ExampleObject;
+import io.swagger.v3.oas.annotations.media.Schema;
+import io.swagger.v3.oas.annotations.responses.ApiResponse;
+
 import org.springframework.http.HttpStatus;
-import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -32,15 +51,22 @@ public OrderController(OrderService orderService) {
      * @param order the order
      * @return the response entity
      */
+    @Operation(summary = ADD_ORDER_KAFKA_SUMMARY, description = ADD_ORDER_DESCRIPTION,
+            requestBody = @io.swagger.v3.oas.annotations.parameters.RequestBody(required = true,
+                    content = @Content(schema = @Schema(implementation = Order.class),
+                            examples = @ExampleObject(ADD_ORDER_REQUEST_EXAMPLE))),
+            responses = @ApiResponse(
+            responseCode = "201",
+            content = @Content(
+                    schema = @Schema(implementation = APIResponse.class),
+                    examples = @ExampleObject(ADD_ORDER_OK_RESPONSE_EXAMPLE)
+            )
+    ))
     @PostMapping("/kafka")
-    public ResponseEntity<ApiResponse<String>> makeOrderKafka(@RequestBody OrderDto orderDto) {
+    public APIResponse<String> makeOrderKafka(@RequestBody Order orderDto) {
         orderService.sendOrderToKafka(orderDto);
-        ApiResponse<String> apiResponse = new ApiResponse<>(
-                HttpStatus.OK.value(),
-                "Order sent to kafka successfully!",
-                null
-        );
-        return new ResponseEntity<>(apiResponse, HttpStatus.OK);
+        return ResponseUtil.createUnifiedResponse(CREATED.value(),
+                ADD_ORDER_SUCCESSFUL_MESSAGE,null);
     }
 
     /**
@@ -49,16 +75,21 @@ public ResponseEntity<ApiResponse<String>> makeOrderKafka(@RequestBody OrderDto
      * @param order the order
      * @return the response entity
      */
+    @Operation(summary = ADD_ORDER_DB_SUMMARY, description = ADD_ORDER_DESCRIPTION,
+            requestBody = @io.swagger.v3.oas.annotations.parameters.RequestBody(required = true,
+                    content = @Content(schema = @Schema(implementation = Order.class),
+                            examples = @ExampleObject(ADD_ORDER_REQUEST_EXAMPLE))), responses = @ApiResponse(
+            responseCode = "201",
+            content = @Content(
+                    schema = @Schema(implementation = APIResponse.class),
+                    examples = @ExampleObject(ADD_ORDER_OK_RESPONSE_EXAMPLE)
+            )
+    ))
     @PostMapping("/db")
-    public ResponseEntity<ApiResponse<String>> makeOrderDatabase(@RequestBody OrderDto order) {
-        Order convertedOrder = new Order(order.name(),order.description());
-        orderService.sendOrderToDatabase(convertedOrder);
-        ApiResponse<String> apiResponse = new ApiResponse<>(
-                HttpStatus.OK.value(),
-                "Order sent to database successfully!",
-                null
-        );
-        return new ResponseEntity<>(apiResponse, HttpStatus.OK);
+    public APIResponse<String> makeOrderDatabase(@RequestBody Order order) {
+        orderService.sendOrderToDatabase(order);
+        return ResponseUtil.createUnifiedResponse(CREATED.value(),ADD_ORDER_SUCCESSFUL_MESSAGE
+                ,null);
     }
 
     /**
@@ -67,15 +98,19 @@ public ResponseEntity<ApiResponse<String>> makeOrderDatabase(@RequestBody OrderD
      * @return the response entity
      * @throws Exception the exception
      */
+    @Operation(summary = START_BATCH_SUMMARY_DB + " from database", description = START_BATCH_DESCRIPTION,
+            responses = @ApiResponse(
+            responseCode = START_BATCH_OK,
+            content = @Content(
+                    schema = @Schema(implementation = APIResponse.class),
+                    examples = @ExampleObject(START_BATCH_OK_RESPONSE_EXAMPLE)
+            )
+    ))
     @PostMapping("/batch-db")
-    public ResponseEntity<ApiResponse<String>> batchProcessDB() throws Exception {
+    public APIResponse<String> batchProcessDB() throws Exception {
         orderService.batchProcess(BatchReadType.DATABASE);
-        ApiResponse<String> apiResponse = new ApiResponse<>(
-                HttpStatus.OK.value(),
-                "Batch processing from db started successfully!",
-                null
-        );
-        return new ResponseEntity<>(apiResponse, HttpStatus.OK);
+        return ResponseUtil.createUnifiedResponse(HttpStatus.OK.value(),
+                BATCH_SUCCESS_MESSAGE,null);
     }
 
     /**
@@ -84,15 +119,19 @@ public ResponseEntity<ApiResponse<String>> batchProcessDB() throws Exception {
      * @return the response entity
      * @throws Exception the exception
      */
+    @Operation(summary = START_BATCH_SUMMARY_KAFKA, description = START_BATCH_DESCRIPTION,
+            responses = @ApiResponse(
+            responseCode = START_BATCH_OK,
+            content = @Content(
+                    schema = @Schema(implementation = APIResponse.class),
+                    examples = @ExampleObject(START_BATCH_OK_RESPONSE_EXAMPLE)
+            )
+    ))
     @PostMapping("/batch-kafka")
-    public ResponseEntity<ApiResponse<String>> batchProcessKafka() throws Exception {
+    public APIResponse<String> batchProcessKafka() throws Exception {
         orderService.batchProcess(BatchReadType.KAFKA);
-        ApiResponse<String> apiResponse = new ApiResponse<>(
-                HttpStatus.OK.value(),
-                "Batch processing from kafka started successfully!",
-                null
-        );
-        return new ResponseEntity<>(apiResponse, HttpStatus.OK);
+        return ResponseUtil.createUnifiedResponse(HttpStatus.OK.value(),
+                BATCH_SUCCESS_MESSAGE,null);
     }
 
 }

src/main/java/com/ittovative/batchprocessing/util/BatchReadType.java → src/main/java/com/ittovative/batchprocessing/enums/BatchReadType.java

@@ -1,4 +1,4 @@
-package com.ittovative.batchprocessing.util;
+package com.ittovative.batchprocessing.enums;
 
 /**
  * The enum Batch read type.