Skip to main content

Setting up Spring Cloud Data Flow Server

Spring cloud data flow server can be used to setup the pipeline of tasks or streams. Tasks and streams can be registered with data flow server and can be executed or monitored either using cloud data flow shell or data flow server UI console/ dashboard.

Setting up Data flow server

Spring cloud data flow server can be setup using two ways, either use spring provided spring boot application or develop your own spring cloud data flow server as spring boot application.

Using Spring provided Data flow server application

There are many ways to setup data flow server as given below.
  • Local Machine
  • Cloud Foundry
  • Kubernetes
Please refer below documentation for more details for above installation types.
https://dataflow.spring.io/docs/installation/

Create Spring boot application as Data flow server

Here I will show you how to create your own spring boot application as spring cloud data flow server which you can run anywhere locally or in cloud. It gives you more freedom with application to setup the other dependencies like database or security features.

Maven Dependencies

We have used Spring Boot version 2.1.6.RELEASE which is supported by the current version of data flow server (2.2.1.RELEASE). Below are the dependencies required in pom.xml
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-dataflow-server</artifactId>
            <version>2.2.1.RELEASE</version>
        </dependency>

application.properties

In this properties file we are just creating an in-memory database using H2. However it is not required as it will automatically setup one if we don't configure it. We can use these properties to use any other database.
spring.datasource.url=jdbc:h2:tcp://localhost:19092/mem:dataflow
spring.datasource.jdbcUrl=jdbc:h2:tcp://localhost:19092/mem:dataflow
spring.datasource.driverClassName=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=

spring.jpa.database-platform=org.hibernate.dialect.H2Dialect

MainDataFlowServerApplication.java

This is our main class which need to be annotated  with @EnableDataFlowServer annotation. Since we are going to run this application in our local machine, we need to exclude some auto configurations like cloud foundry, kubernetes etc. until we intend to actually configure them. When required we can remove them from exclusions and configure necessary properties for auto configuration. See the below code.
@EnableDataFlowServer
@SpringBootApplication(
        exclude = {SessionAutoConfiguration.class,
                ManagementWebSecurityAutoConfiguration.class,
                SecurityAutoConfiguration.class,
                UserDetailsServiceAutoConfiguration.class,
                LocalDeployerAutoConfiguration.class,
                CloudFoundryDeployerAutoConfiguration.class,
                KubernetesAutoConfiguration.class}
)
public class MainDataFlowServerApplication {

    public static void main(String[] args) {
        SpringApplication.run(MainDataFlowServerApplication.class, args);
    }
}

Git URL

Below GIT URL contains complete source code.
https://github.com/thetechnojournals/spring-tutorials/tree/master/SpringCloudDataFlowServer

Running data flow server application

Once you done with all required code and configuration setup, you can build the application and use below maven command to start your data flow server.
mvn spring-boot:run
Once application is started, hit the below URL in browser and you will see the given screen as dashboard of data flow server application where you can see all registered task and streams.\
URL: http://localhost:9393/dashboard/

spring-cloud-dataflow-server

Check my another post on registering and executing Spring Batch application with Spring cloud data flow server.
https://www.thetechnojournals.com/2019/12/spring-batch-job-with-spring-cloud-data.html

Comments

Popular Posts

SpringBoot - @ConditionalOnProperty example for conditional bean initialization

@ConditionalOnProperty annotation is used to check if specified property available in the environment or it matches some specific value so it can control the execution of some part of code like bean creation. It may be useful in many cases for example enable/disable service if specific property is available. Below are the attributes which can be used for property check. havingValue - Provide the value which need to check against specified property otherwise it will check that value should not be false. matchIfMissing - If true it will match the condition and execute the annotated code when property itself is not available in environment. name - Name of the property to be tested. If you want to test single property then you can directly put the property name as string like "property.name" and if you have multiple properties to test then you can put the names like {"prop.name1","prop.name2"} prefix - It can be use when you want to apply some prefix to

Asynchronous REST service implementation in Spring boot

In this tutorial we will see how to create an asynchronous REST service endpoint using Spring boot application. Asynchronous service works in a way that it will not block the client request and do the processing in separate thread. When work is complete the response returned to the client so our service will be able to handle more client requests at the same time, compare to synchronous processing model. Let's understand how it is working in synchronous mode. In such server/client application at server side it has a pool of threads which are serving the request. If a request received by a thread then it will be blocked until it send the response back to client. In this case if processing doesn't take much time it will be able to process it quickly and accept other client requests but there could be one situation when all threads are busy and not able to accept the new client requests. To overcome of such problems, asynchronous processing model introduced for REST service

Entity to DTO conversion in Java using Jackson

It's very common to have the DTO class for a given entity in any application. When persisting data, we use entity objects and when we need to provide the data to end user/application we use DTO class. Due to this we may need to have similar properties on DTO class as we have in our Entity class and to share the data we populate DTO objects using entity objects. To do this we may need to call getter on entity and then setter on DTO for the same data which increases number of code line. Also if number of DTOs are high then we need to write lot of code to just get and set the values or vice-versa. To overcome this problem we are going to use Jackson API and will see how to do it with minimal code only. Maven dependency <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.9.9</version> </dependency> Entity class Below is

Setting up kerberos in Mac OS X

Kerberos in MAC OS X Kerberos authentication allows the computers in same domain network to authenticate certain services with prompting the user for credentials. MAC OS X comes with Heimdal Kerberos which is an alternate implementation of the kerberos and uses LDAP as identity management database. Here we are going to learn how to setup a kerberos on MAC OS X which we will configure latter in our application. Installing Kerberos In MAC we can use Homebrew for installing any software package. Homebrew makes it very easy to install the kerberos by just executing a simple command as given below. brew install krb5 Once installation is complete, we need to set the below export commands in user's profile which will make the kerberos utility commands and compiler available to execute from anywhere. Open user's bash profile: vi ~/.bash_profile Add below lines: export PATH=/usr/local/opt/krb5/bin:$PATH export PATH=/usr/local/opt/krb5/sbin:$PATH export LDFLAGS=&