Showing posts with label Spring Boot. Show all posts
Showing posts with label Spring Boot. Show all posts

Tuesday, May 5, 2020

Creating first Jenkins pipeline: tutorial

Jenkins uses a feature called Jenkins Pipeline which is a collection of jobs that brings the software from version control into the hands of the end-users by using automation tools. They represent multiple Jenkins jobs as one whole workflow in the form of a pipeline.

In this blog, I am going to share my knowledge on how can we write multiple Jenkins jobs as a pipeline and it uses two different syntaxes i.e. Declarative and Scripted pipeline and in our examples, we're going to use the Scripted Pipeline which is following a more imperative programming model built with Groovy.

  • Code on bitbucket/GitHub
  • Jenkins Installation
  • Download required plugins to run pipelines like Pipeline, SonarQube Scanner, Check Style, Junit, Git Integration, Maven Integration.
  • Sonar up and running. 
Let’s start creating pipeline will do below tasks:
  • Clone Project from Jenkins
  • Build and run Junit test cases
  • Run Sonar
  • Run Checkstyle
  • Package it as a jar file

Configuration Steps: 
  • Let's create new Jenkins jobs. Goto Jenkins -> New Item
  • Add name under 'Enter an item name', Select pipeline as the type, and click Ok button.

  • I am skipping the description and others tab here and directly jumping to the Pipeline tab as I already discussed it in my previous blog and we can run pipeline without worrying about it.
  • Add below script and check Use Groovy Sandbox and Save it.

node {
// clone the project from Github
    git ''
//Build the project
  sh "mvn clean install"
// Run Sonar for Code Coverage
       // Ignore this stage if sonar instance is not present
stage('Sonar') {
sh "mvn sonar:sonar"
// Run code check
stage("Checkstyle") {
        sh "mvn checkstyle:checkstyle"
        step([$class: 'CheckStylePublisher',
          canRunOnFailed: true,
          defaultEncoding: '',
          healthy: '100',
          pattern: '**/target/checkstyle-result.xml',
          unHealthy: '90',
          useStableBuildAsReference: true
    //package the application
     stage('Package') {
         junit '**/target/surefire-reports/TEST-*.xml'
         archiveArtifacts 'target/*.jar'

  • To configure Sonarqube URL, Goto Jenkins -> Manage Jenkins -> Configure System and set Server URL and save it. 
  • You can see your newly created pipeline on the Jenkins dashboard

  • Click on Jenkins-pipeline-demo and then on the right side, click on Build now to build the project, to start the Jenkins pipelines.

  • Once your job is completed, you will see below screen 

  • As the final job was packing as the jar. you can see a blue downward arrow button clicking on which will download your application as a JAR file.
  • you can check the logs by clicking on the blue circle button on the left side or you can hover over a stage cell and click the Logs button.

  • To Check Sonar report, goto Sonar Server URL that you configured it. It will show you total code coverage, unused import, and bad code.

  • We had also added the Checkstyle stage to the pipeline so to check the report. Click on the Checkstyle Warning present below build now link.

  • Here we see 12 High Priority Warning browsable by clicking it. The Details tab gives you more insight into each class error. 
Conclusion :
We are able to set up a simple Jenkins pipeline to show code pull, build, to run sonar, and other code analysis tools, and as always the source code used in this project can be found over on Github.

Wednesday, April 22, 2020

Continuous Integration with Jenkins and Spring Boot App

Jenkins can be used for multiple purposes like whenever any developer commits any code changes to SCM, Jenkins triggers job which can Checkout the code, build it, run JUnit test case, run tools like sonar or checkmarx and if everything works properly then deploy it to some instance.

In this tutorial, I’ll share my knowledge on how can we automate our test process by introducing CI like Jenkins. We will configure Jenkins such that it should trigger it whenever any code commits by any developer to SCM, pull out the code from GIT, run maven to build and test the code.

  • Code upload on GIT (or use this link)
  • Jenkins up and running. Refer here for installation.
  Once your Jenkins is up and running then you will see below screen

  Configuration Steps:
·       Install the required plugin.
o   Make sure all the required plugins like GIT, Maven are already present
o   Goto Manage Jenkins -> manage plugins -> Installed tab

o   In case, if you don’t find the required plugin then search under the Available tab. E.g. to install the Maven Integration plugin.
o   Select plugin and click on Download now and install after restart.

o   It will take some time to download and install the plugin as per your network bandwidth.

     Set Java and Maven Path
o   by default, Jenkins pick up the JAVA and Maven path running on Ubuntu instance but if you have any specific java or maven directory then you can configure those as well.
o   Goto Manage Jenkins -> Global tool configuration

      Generate SSH keygen for Jenkins user
o   If you want to access a private Git repo, for example at GitHub, you need to generate an ssh key-pair. Create a SSH key with the following command.

o   The public-key must be uploaded to the service you are using, e.g., GitHub.

·       Setting up Jenkins job
o   The build of a project is handled via jobs in Jenkins. Click New Item. Afterward, enter a name for the job and select the Freestyle Project and press OK.

o   Add description of the job
o   Check Discard old builds. It will help you in cleaning the stale log. You can choose the log rotation based on the number of builds or days. Always enable and choose this option to make sure you are not running out of memory of Jenkins log.

o   Under Source code Management choose Git as we are going to checkout the code from GIT.SET git url ( and no need of credential as my repo is public and set branch as master.

o   Under Build triggers, choose poll SCM so that it should run this job whenever someone commit the code to the master branch.
o   Schedule value in * which defines the time.

o   Which means pull the SCM every day of every month and every minute of every hour.
o   Select top-level maven targets under Build and set Goals as clean package.

o   Apply and save the configuration.

·       Run the build
o   Job is created as jenkins-demo.

o   Click on jenkins-demo and then Build now to run the newly created job.

·       Congratulation! Your first job is created successfully and the blue circle under Build history means there was no issue during job execution and it ran successfully.

Friday, November 8, 2019

Streaming Spring boot logs to ELK stack

In my previous blog, we have done ELK installation on windows 10 and we have even tried to push messages from input console to Elastic Search and finally viewed on Kibana Server.

I will write a separate blog on why do we need ELK?

In this blog, I’ll show you how can we push spring boot application log directly to Elastic search using Logstash which we can analyze on Kibana and If you don’t know how to install ELK on windows 10 then you can refer my previous blog and start Elastic Search and Kibana server.


  • Elastic Search and Kibana running on your machine
  • Basic knowledge of Spring boot application

If you don’t want to start your application from scratch then you can download one spring boot application from my GitHub repository as well.

I am assuming that the Elastic Search and Kibana server are running on your machine and you have a fair idea of how to start the Logstash server and what is Logstash conf file.

So, to push spring boot logs continuously to Elastic Server, We have to open one TCP port in Logstash server and for that we have to create one Logstash config file (say elklogstash.conf) under ${LOGSTASH_HOME}/conf directory mentioning on which port TCP port should be listening under input filter and where to push the data once we received under Output filter.

For simplicity, I am skipping the filter tag as it is optional.


Now start the Logstash server bypassing newly created conf file.
   bin\logstash -f .\config\elklogstash.conf

Cool! Now Logstash server is also up and running and if you observe the log, you will realize that it is also listening on port 4560 as mentioned in the conf file. Configure the newly created index (elkbootlogs) on Kibana as we have done during the ELK setup.

Now let's do some changes to spring boot application so that it can push all the logs to 4056 TCP port.

For this tutorial, I am using spring-logger project from my Github repository.

Add below dependency to the pom.xml file. We need Logstash encoder to encode messages.

<!-- Added for logstash Encoder-->


Open logback-spring.xml file which is under the resource folder and create new appender (say elk). The task of this appender is to push logs to the destination TCP socket and under this appender, compulsory use LogstashEncoder.

<appender name="elk" class="net.logstash.logback.appender.LogstashTcpSocketAppender">
    <!-- encoder is required -->
    <encoder class="net.logstash.logback.encoder.LogstashEncoder" />


Add new appender to root level

<!-- LOGGING everything at INFO level -->
<root level="info">
<appender-ref ref="RollingFile" />
<appender-ref ref="Console" />
<appender-ref ref="elk" />

Save all files and start your application. So, we are done with all the setup. Its time to check whether all the changes are done properly or not.

Open Kibana on your browser (http://localhost:5601) and select your index under the Discover tab. You will see all logs are populating on Kibana as well.

Congratulations! Our configuration is working absolutely fine and it is pushing logs to Elastic Search. 

You can download the source code from here, ELK code chnages are under elkstack branch.

Sunday, November 3, 2019

How to create Docker Image and push java app in a Docker Engine

In this blog, I am going to share my knowledge on the creation of a docker image and how can we run in a Docker Engine.


  • Basic Knowledge of Docker
  • Docker must be running on your machine.
  • Good to aware of Spring boot application.
I already have one spring boot application in my IntelliJ which expose one endpoint /users/{id}. We will see how can we push and run this application in a docker container. 

We need to create one file named Dockerfile to add docker instruction (Check above image).

Now go to Terminal and check whether the docker is running or not on your machine.

Run docker build to create an image and push it to the container using the command.
docker build -f Dockerfile -t docker-spring-ehcache .

The above command will execute all the operations that we have mentioned in our Dockerfile like pulling OpenJDK 8 from the docker hub if not exist.

Let's see if our image got pushed to docker containers or not by listing all docker images.
docker images

Great! Our image is present in the docker container. Let's run it.
docker run -p 8070:8085 docker-spring-ehcache

Over here, we are telling the Docker to start the application and map docker container port 8085 to our local port 8070. 

Note: Make sure your application has started at 8085 in docker container else it won't be able to map it. Spring boot by default start application on port 8080 so please specify server.port-8050 in file.

Now go to your browser and hit the endpoint and see if we are getting the response from localhost:8070 or not.

Happy Coding!!!

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