Calling REST Controller from maven dependency - spring-boot

Question

Suppose I have a SpringBoot 2.2.6 WebApp calls app-client and a Maven module calls common-crud where I need to insert some commons Controller. For just an example suppose that the common-crud has just a package with just the follow Controller:
#GetMapping("/sayHelloFromModule")
public ResponseEntity<String> sayHello() {
return new ResonseEntity<String>("Hello", HttpStatus.OK);
}
the .pom.xml of the common-crud maven module is as follows:
<project..
<groupId>com.common</groupId>
<artifactId>common-crud</artifactId>
<version>0.0.1</version>
<packaging>jar</packaging>
<name>common-crud</name>
<properties>
...
</properties>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.6.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
</project>
The app-client is a SpringBoot app and have it's main and so on.. the .pom.xml is:
<project..
<groupId>com.mainapp</groupId>
<artifactId>app-client</artifactId>
<version>0.0.1</version>
<packaging>war</packaging>
<name>app-client</name>
<properties>
...
</properties>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.6.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.common</groupId>
<artifactId>common-crud</artifactId>
<version>0.0.1</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
The main-app is deployed on external Tomcat 8.5.53 with contextRoot mainapp. Now if I open a browser and call:
http://localhost:8080/app-client/<some-controller-inside-mainapp>
It clearly works with no problem.. if I call:
http://localhost:8080/app-client/sayHelloFromModule
throws me Error 404. I don't know if I can realize it in some ways or it is just a bad practice and cannot work in any circumstances.
Clearly the real scenario is more complex.. and the library module should use to profile different type of SpringSecurity Authentication (SAML, JWT, Oauth2.. and so on).
Is there a way to achieve this??
Thank you

Answer 1

It was easier than they appear. In the Main class of mainapp
#SpringBootApplication
#ComponentScan({
"com.client.oauth",
"com.client.resources",
"com.client.security.config",
"com.auth0.core.common",
"com.auth0.core.provider"
})
public class OauthClientApplication extends SpringBootServletInitializer {}
the dependencies packages should be imported