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Integrating Camunda webapps in spring framework

I setup Camunda in my Spring 3 project (Tomcat server) using this guide. I embedded the workflow engine in my project.
However, I cannot access the cockpit when I go to the url http://localhost:8080/camunda/app/. I get a 404 error.
I see that there is a dependency to be added in case of Spring boot according to this guide
But I see no such dependencies available for Spring. Do we not get access to webapps while integrating Camunda with Spring?
Also asked this question in the camunda form: https://forum.camunda.org/t/integrating-camunda-webapps-in-spring-framework/27661

You'll need the following dependency.
<dependency>
<groupId>org.camunda.bpm.webapp</groupId>
<artifactId>camunda-webapp-webjar</artifactId>
</dependency>
Then ensure you have the required configurations. Refer the spring boot auto configuration set up here and the web app initialiser here.

spring boot wants me to start server because I have servlet on classpath

today I faced following problem:
One of my core dependencies unfortunately pulls servlet.api to my classpath. Because of this, my spring-boot thinks I'm automatically a server, while I'm a desktop app, and does not want to start without some factories needed to web.
This is what it says:
Caused by: org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
Unfortunately I can't get rid of this dependency, and for them to fix their transitive dependencies will probably take some time.
Is there any hack to walk around this?
Thanks

If you're using Spring boot 2.x, you can disable the web application by setting the spring.main.web-application-type property to none:
spring.main.web-application-type=none
If you're using Spring boot 1.x, you could set the spring.main.web-environment property:
spring.main.web-environment=false
The reason this changed is because Spring boot 2.x can now be configured to be either reactive, servlet-based or none, while in Spring boot 1.x it was either servlet-based or none (so it could be just a boolean).
Alternatively, you can also use a custom SpringApplication instance as mentioned by the documentation (and in the comments):
public static void main(String[] args) {
new SpringApplicationBuilder(Application.class)
.web(WebApplicationType.NONE) // Use this for Spring boot 2.x
.web(false) // Use this for Spring boot 1.x
.run(args);
}
Not all Spring applications have to be web applications (or web services). If you want to execute some code in a main method but also bootstrap a Spring application to set up the infrastructure to use, you can use the SpringApplication features of Spring Boot. A SpringApplication changes its ApplicationContext class, depending on whether it thinks it needs a web application or not. The first thing you can do to help it is to leave server-related dependencies (e.g. servlet API) off the classpath. If you cannot do that (for example, you run two applications from the same code base) then you can explicitly call setWebApplicationType(WebApplicationType.NONE) on your SpringApplication instance or set the applicationContextClass property (through the Java API or with external properties).

You are missing some required JAR file to run it as web application. Please make sure to that you have included spring-boot-starter-web.jar file.
If we are using maven, do it as follows.
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>1.3.2.RELEASE</version>
</dependency>

Apply /refresh on multiple instances annotated with #refreshScope

I'm writing spring boot application, which using spring configuration, deployed on pivotal cloud foundry and exposed by Netflix Eureka as discovery serivce / load balancer.
I have created a bean as followed:
#Component
#ConfigurationProperties("config")
#RefreshScope
#Data
public class GeneralProperties {
private boolean ignoreEvent;
}
When calling to the application route that Eureka exposed with /refresh after changing the actual property in the configuration repository, the value that annotated by #refreshScope was changed (end in the response status the field exsiting), which means it's working correctly.
The issue starts when running multiple instances of the same application on the cloud, and calling to the /refresh.
The route that beeing used is the one that exposed by Eureka, which using it's load balancer to route the call to one of the available instances.
It leads to unexpected results that not all the instances are getting updated with the latest change in the property.
Any suggestions how to apply the change on all instances?

You should use Spring Cloud Bus in such a case.
The idea behind this framework is to bind all your application instances to a topic in a message broker (RabbitMQ or Apache Kafka).
Add the following dependency to your pom.xml:
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-bus-parent</artifactId>
<version>1.3.2.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-bus-amqp</artifactId>
</dependency>
</dependencies>
In the above example I added a dependency on amqp which is RabbitMQ. You'll also need to bind your application to the RabbitMQ, in PCF it's easy since it's built in to the platform.
When you need to refresh, you should invoke:
POST /bus/refresh
This would trigger an event to a topic that all instances of your application are listening to, and as a result - all instances would refresh their bean configuration.
Good luck.

Spring Cloud Consul /refresh endpoint missing

I'm using Spring Cloud Consul for Distributed Configuration with Consul and all goes fine. All configuration is currently and successfully read from Consul server on startup of the application. But I can't reload this configuration for my app when some data on Consul changed because there is not /refresh endpoint. But here says "Sending a HTTP POST to /refresh will cause the configuration to be reloaded." As I understand it should be like for Spring Cloud Config Client but it doesn't. What did I miss?

You need to include the spring boot actuator
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>

Or add #RefreshScope on your bean for e.g.
#Component
#RefreshScope
public class MyConsulConfig {
#Value("${consul.base.url}")
private String baseUrl;
}

How to prevent auto start of tomcat/jetty in Spring Boot when I only want to use RestTemplate

I want to use RestTemplate/TestRestTemplate by including the artifact in a SpringBoot application
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
</dependency>
But this automatically starts Tomcat or Jetty. Is there a way to turn it off, or by not including the above artifact. TestRestTemplate is in the boot artifact, but not the base RestTemplate.

Spring Boot is not going to start a web container if it's not present. spring-web does not provide any embedded container. You may want to analyse the dependencies of your project (try mvn dependency:tree).
If you want to make sure a web server is not started in your spring boot application, you can set the following configuration key
spring.main.web-application-type=none
Or you can use the SpringApplicationBuilder
new SpringApplicationBuilder(YourApp.class)
.web(WebApplicationType.NONE).run(args);

Since Spring Boot 2.0.0 this property is deprecated and following is the new way:
spring.main.web-application-type=none
This change is because Spring Boot the support for reactive server.

You can just close the app according to https://spring.io/guides/gs/async-method/. Although this still stars Tomcat, but will stop the app at the end without keeping the tread running.
SpringApplication.run(MyApp.class, args).close();