Add example for Spring Modulith (#222)

Author: rashidi

.github/workflows/build-and-publish-antora.yml

@@ -4,7 +4,6 @@ on:
   push:
     branches:
       - master
-      - docs/**
     paths:
       - 'docs/**'
       - 'antora-playbook.yml'

README.adoc

@@ -62,4 +62,5 @@ All tutorials are documented in AsciiDoc format and published as an https://anto
 |link:test-rest-assured[Spring Test: Integration with RestAssured] | Implement Behaviour Driven Development with https://rest-assured.io/[RestAssured]
 |link:test-slice-tests-rest[Spring Test: Implementing Slice Tests for REST application] | Dive into available options to implement tests with Spring Boot's test components
 |link:web-rest-client[Spring Web: REST Clients for calling Synchronous API] | Implement REST client to perform synchronous API calls
+|link:modulith[Spring Modulith: Building Modular Monolithic Applications] | Structure Spring Boot applications into well-defined modules with clear boundaries
 |===

docs/modules/ROOT/nav.adoc

@@ -18,6 +18,8 @@
 ** xref:data-rest-validation.adoc[REST Validation]
 * Spring GraphQL
 ** xref:graphql.adoc[GraphQL Server]
+* Spring Modulith
+** xref:modulith.adoc[Building Modular Monolithic Applications]
 * jOOQ
 ** xref:jooq.adoc[jOOQ]
 * Spring Test
@@ -26,4 +28,4 @@
 ** xref:test-rest-assured.adoc[Integration with RestAssured]
 ** xref:test-slice-tests-rest.adoc[Implementing Slice Tests for REST application]
 * Spring Web
-** xref:web-rest-client.adoc[REST Clients for calling Synchronous API]
+** xref:web-rest-client.adoc[REST Clients for calling Synchronous API]

docs/modules/ROOT/pages/batch-rest-repository.adoc

@@ -1,5 +1,7 @@
 = Spring Batch: Working With REST Resources
 :source-highlighter: highlight.js
+Rashidi Zin <rashidi@zin.my>
+2.0, September 27, 2023
 :nofooter:
 :icons: font
 :url-quickref: https://github.com/rashidi/spring-boot-tutorials/tree/master/batch-rest-repository
@@ -22,39 +24,48 @@ consists of `ItemReader` and `ItemWriter`. We will implement all of them in link
 ----
 @Configuration
 class UserJobConfiguration {
+
     private final JobRepository jobRepository;
     private final PlatformTransactionManager transactionManager;
     private final MongoOperations mongo;
+
     UserJobConfiguration(JobRepository jobRepository, PlatformTransactionManager transactionManager, MongoOperations mongo) {
         this.jobRepository = jobRepository;
         this.transactionManager = transactionManager;
         this.mongo = mongo;
     }
+
     @Bean
     public Job userJob() throws MalformedURLException {
         return new JobBuilder("userJob", jobRepository).start(step()).build();
     }
+
     private Step step() throws MalformedURLException {
         return new StepBuilder("userStep", jobRepository)
                 .<User, User>chunk(10, transactionManager)
                 .reader(reader())
                 .writer(writer())
                 .build();
     }
+
     private JsonItemReader<User> reader() throws MalformedURLException {
         JacksonJsonObjectReader<User> jsonObjectReader = new JacksonJsonObjectReader<>(User.class);
+
         jsonObjectReader.setMapper(new ObjectMapper());
+
         return new JsonItemReaderBuilder<User>()
                 .name("userReader")
                 .jsonObjectReader(jsonObjectReader)
                 .resource(new UrlResource("https://jsonplaceholder.typicode.com/users"))
                 .build();
     }
+
     private MongoItemWriter<User> writer() {
         return new MongoItemWriterBuilder<User>()
                 .template(mongo)
                 .build();
     }
+
 }
 ----
 
@@ -64,15 +75,19 @@ From the code above, we can see that a `URL` form of `Resource` is assigned to `
 ----
 @Configuration
 class UserJobConfiguration {
+
     private JsonItemReader<User> reader() throws MalformedURLException {
         JacksonJsonObjectReader<User> jsonObjectReader = new JacksonJsonObjectReader<>(User.class);
+
         jsonObjectReader.setMapper(new ObjectMapper());
+
         return new JsonItemReaderBuilder<User>()
                 .name("userReader")
                 .jsonObjectReader(jsonObjectReader)
                 .resource(new UrlResource("https://jsonplaceholder.typicode.com/users"))
                 .build();
     }
+
 }
 ----
 
@@ -88,27 +103,37 @@ Once completed then we will verify that the database contains the expected numbe
 @SpringBatchTest
 @SpringBootTest(classes = { BatchTestConfiguration.class, MongoTestConfiguration.class, UserJobConfiguration.class }, webEnvironment = NONE)
 class UserBatchJobTests {
+
     @Container
     @ServiceConnection
     private final static MySQLContainer<?> MYSQL_CONTAINER = new MySQLContainer<>("mysql:latest")
             .withInitScript("org/springframework/batch/core/schema-mysql.sql");
+
     @Container
     @ServiceConnection
     private final static MongoDBContainer MONGO_DB_CONTAINER = new MongoDBContainer("mongo:latest");
+
     @Autowired
     private JobLauncherTestUtils launcher;
+
     @Autowired
     private MongoOperations mongoOperations;
+
     @Test
     @DisplayName("Given there are 10 users returned from REST Service When the job is COMPLETED Then all users should be saved to MongoDB")
     void launch() {
+
         await().atMost(ofSeconds(30)).untilAsserted(() -> {
             var execution = launcher.launchJob();
+
             assertThat(execution.getExitStatus()).isEqualTo(COMPLETED);
         });
+
         var persistedUsers = mongoOperations.findAll(User.class);
+
         assertThat(persistedUsers).hasSize(10);
     }
+
 }
 ----
 

docs/modules/ROOT/pages/batch-skip-step.adoc

@@ -1,13 +1,15 @@
 = Spring Batch: Skip Specific Data
 :source-highlighter: highlight.js
+Rashidi Zin <rashidi@zin.my>
+2.0, October 1, 2023
 :nofooter:
 :icons: font
 :url-quickref: https://github.com/rashidi/spring-boot-tutorials/tree/master/batch-skip-step
 
 Skip processing specific data through business logic in Spring Batch.
 
-
 == Background
+
 Spring Batch is a framework for batch processing – execution of a series of jobs. A job is composed of a series of steps.
 Each step consists of a reader, a processor, and a writer. The reader reads data from a data source, the processor
 processes the data, and the writer writes the processed data to a data source.
@@ -21,25 +23,30 @@ Our application will process data from link:{url-quickref}/src/main/resources/us
 into MySQL database. Content of `users.json` is taken from link:https://jsonplaceholder.typicode.com/users[JSONPlaceholder].
 
 == Implement Logics to Skip Data
+
 === Returning `null`
+
 First approach is to return `null` from `ItemProcessor` implementation. This approach is straight forward and does not
 require additional configuration.
 
 [source,java]
 ----
 @Configuration
 class UserJobConfiguration {
+
     private ItemProcessor<UserFile, User> processor() {
         return item -> switch (item.username()) {
             case "Elwyn.Skiles" -> null;
         };
     }
+
 }
 ----
 
 With that, when the `Job` detected that the `ItemProcessor` returns `null`, it will skip the data and continue to the next.
 
 === Throwing `RuntimeException`
+
 Second approach is to throw `RuntimeException` from `ItemProcessor` implementation. This approach requires additional
 configuration to be done when defining `Step`.
 
@@ -49,15 +56,19 @@ Implementation in `ItemProcessor` is as follows:
 ----
 @Configuration
 class UserJobConfiguration {
+
     private ItemProcessor<UserFile, User> processor() {
         return item -> switch (item.username()) {
             case "Maxime_Nienow" -> throw new UsernameNotAllowedException(item.username());
         };
     }
+
     static class UsernameNotAllowedException extends RuntimeException {
+
         public UsernameNotAllowedException(String username) {
             super("Username " + username + " is not allowed");
         }
+
     }
 }
 ----
@@ -68,6 +79,7 @@ Next is to inform `Step` to skip `UsernameNotAllowedException`:
 ----
 @Configuration
 class UserJobConfiguration {
+
     private Step step(JobRepository jobRepository, PlatformTransactionManager transactionManager, DataSource dataSource) {
         return new StepBuilder("userStep", jobRepository)
                 .<UserFile, User>chunk(10, transactionManager)
@@ -76,14 +88,15 @@ class UserJobConfiguration {
                 .skipLimit(1)
                 .build();
     }
+
 }
 ----
 
 With that, when the `Job` detected that the `ItemProcessor` throws `UsernameNotAllowedException`, it will skip the data.
-
 Full definition of the `Job` can be found in link:{url-quickref}/src/main/java/zin/rashidi/boot/batch/user/UserJobConfiguration.java[UserJobConfiguration.java].
 
 == Verification
+
 We will implement integration tests to verify that our implementation is working as intended whereby `Elwyn.Skiles` and
 `Maxime_Nienow` are skipped thus will not be available in the database.
 
@@ -104,25 +117,33 @@ We will implement integration tests to verify that our implementation is working
         statements = "CREATE TABLE IF NOT EXISTS users (id BIGINT PRIMARY KEY, name text, username text)"
 )
 class UserBatchJobTests {
+
     @Container
     @ServiceConnection
     private final static MySQLContainer<?> MYSQL_CONTAINER = new MySQLContainer<>("mysql:latest");
+
     @Autowired
     private JobLauncherTestUtils launcher;
+
     @Autowired
     private JdbcTemplate jdbc;
+
     @Test
     @DisplayName("Given the username Elwyn.Skiles and Maxime_Nienow are skipped, When job is executed, Then users are not inserted into database")
     void findAll() {
+
         await().atMost(10, SECONDS).untilAsserted(() -> {
             var execution = launcher.launchJob();
             assertThat(execution.getExitStatus()).isEqualTo(COMPLETED);
         });
+
         var users = jdbc.query("SELECT * FROM users", (rs, rowNum) ->
                 new User(rs.getLong("id"), rs.getString("name"), rs.getString("username"))
         );
+
         assertThat(users).extracting("username").doesNotContain("Elwyn.Skiles", "Maxime_Nienow");
     }
+
 }
 ----