= Spring Modulith
:docs: https://docs.spring.io/spring-modulith/docs/current-SNAPSHOT/reference/html/

Spring Modulith allows developers to build well-structured Spring Boot applications and guides developers in finding and working with link:{docs}#fundamentals.modules.application-modules[application modules] driven by the domain.
It supports the link:{docs}#verification[verification] of such modular arrangements, link:{docs}#testing[integration testing] individual modules, link:{docs}#observability[observing] the application's behavior on the module level and creating link:{docs}#documentation[documentation snippets] based on the arrangement created.

== Quickstart

. Create a Spring Boot application on https://start.spring.io
. Add Spring Modulith to your application by adding this to your `pom.xml`:
+
[source, xml]
----
<!-- The Maven repository to pull the dependencies from -->
<repositories>
  <repository>
    <id>spring-snapshots</id>
    <url>https://repo.spring.io/snapshot</url>
  </repository>
</repositories>

<!-- Include the BOM for simplified version management -->
<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>org.springframework.modulith</groupId>
      <artifactId>spring-modulith-bom</artifactId>
      <version>1.0.0-SNAPSHOT</version>
      <scope>import</scope>
      <type>pom</type>
    </dependency>
  </dependencies>
</dependencyManagement>

<dependencies>

  <!-- The test dependency to pull in verification APIs -->

  <dependency>
    <groupId>org.springframework.modulith</groupId>
    <artifactId>spring-modulith-starter-test</artifactId>
    <scope>test</scope>
  </dependency>

</dependencies>
----
. Create a Java package arrangement that puts business modules as link:{docs}#fundamentals[direct sub-packages of the application's main package].
+
[source, text, subs="macros"]
----
□ Example
└─ □ src/main/java
   ├─ □ example           <1>
   |  └─ Application.java
   ├─ □ example.inventory <2>
   |  └─ …
   └─ □ example.order     <2>
      └─ …
----
<1> The application root package
<2> Application module packages
. Create link:{docs}#fundamentals.modules.application-modules[an `ApplicationModules` model], run link:{docs}#verification[verifications] and link:{docs}#documentation[create documentation snippets].
+
[source, java]
----
class ApplicationTests {

  @Test
  void writeDocumentationSnippets() {

    var modules = ApplicationModules.of(Application.class).verify(); <1>

    new Documenter(modules) <2>
      .writeModulesAsPlantUml()
      .writeIndividualModulesAsPlantUml();
  }
}
----
<1> Creates application module model and link:{docs}#verification[verifies its structure].
<2> Renders link:{docs}#documentation[Asciidoctor snippets] (component diagrams, application module canvas) to `target/modulith-docs`.
. Run link:{docs}#testing[integration tests] for individual application modules.
+
[source, text, subs="macros"]
----
□ Example
└─ □ src/test/java
   └─ □ example.order
      └─ OrderModuleIntegrationTests.java
----
+
[source, java]
----
@ApplicationModuleTests
class OrderModuleIntegrationTests {

  @Test
  void someTestMethod() { … }
}
----

== Reference documentation

Find the reference documentation link:{docs}[here].

== Contributing

https://help.github.com/articles/creating-a-pull-request[Pull requests] are welcome. Note, that we expect everyone to follow the https://github.com/spring-projects/.github/blob/main/CODE_OF_CONDUCT.md[code of conduct].

== License
Spring Modulith is Open Source software released under the
https://www.apache.org/licenses/LICENSE-2.0.html[Apache 2.0 license].