🚨 Deprecated

This project has been discontinued in favor of enforcing module boundaries by using Maven Multi-Module projects.

Archer

Archer is a pre-defined set of Architectural Enforcement Rules. The aspect-oriented enforcement of rules is guided by annotations and any violation is reported early at compile time.

Features

• prevents bad code from compiling
• lightweight API
• retroactively applicable
• independent of package structure

Archer defines several different layers:

Layer/Annotation	Description
@Gateway	External service client
@Library	Shared code between any of the layers
@Logic	Business logic
@Model	Business or domain model
@Persistence	Database access layer
@Queue	Asynchronous message queue client
@Resource	Web Service/API
@Scheduler	Background Job

Dependencies

• Java 8
• AspectJ compiler

Installation

Add the following dependencies to your project:

<dependency>
  <groupId>io.github.whiskeysierra</groupId>
  <artifactId>archer-annotations</artifactId>
  <version>${archer.version}</version>
  <scope>provided</scope>
</dependency>
<dependency>
  <groupId>io.github.whiskeysierra</groupId>
  <artifactId>archer-aspectj</artifactId>
  <version>${archer.version}</version>
  <scope>provided</scope>
</dependency>

And configure the AspectJ compiler accordingly:

<plugin>
  <groupId>org.codehaus.mojo</groupId>
  <artifactId>aspectj-maven-plugin</artifactId>
  <version>1.8</version>
  <configuration>
    <aspectLibraries>
      <aspectLibrary>
        <groupId>io.github.whiskeysierra</groupId>
        <artifactId>archer-aspectj</artifactId>
      </aspectLibrary>
    </aspectLibraries>
  </configuration>
  <executions>
    <execution>
      <goals>
        <goal>compile</goal>
      </goals>
    </execution>
  </executions>
</plugin>

Usage

Archer requires you to annotate every class with one of the layer annotations:

@Model
public class Person {

}

@Persistence
public class PersonRepository {

}

@Logic
public class PersonService {

}

@Resource
public class PersonResource {

}

Any call between two layers that is not allowed by a rule will result in a compiler error. The same is true if a class is missing an annotation.

Known issues

• No support for package-level annotations, see here

Getting help

If you have questions, concerns, bug reports, etc, please file an issue in this repository's Issue Tracker.

Getting involved

To contribute, simply make a pull request and add a brief description (1-2 sentences) of your addition or change. For more details check the contribution guidelines.

Credits and references

• Mattias Severson, Architectural Enforcement with Aid of AspectJ
• Martin Fowler, Testing Strategies in a Microservice Architecture