I'm totally new to spring boot/gradle, so if i say something wrong, please feel free to correct me.
I have two spring boot projects and i'm using Spring Boot Gradle Plugin to run one by one in different ports and to also generate the respective jars.
I want to know if it's possible to generate one fat jar that can run both projects in different ports.
Here's the structure of my project:
Project
setting.gradle
Project-1
src/.../#SpringBootApplication Main
build.gradle
Project-2
src/.../#SpringBootApplication Main2
build.gradle
I included both projects in the setting.gradle, the Project-2 in the dependencies of Project-1 and tried gradle clean build, but the fat jar generated in the Project-1 doesn't include the Project-2's jar. What I expected is that when I run the fat jar it exposes the two projects in their respective ports, as if I did gradle bootRun on each project.
Is what i'm doing correct? I'm assuming that putting the Project-2 in the dependencies of Project-1 would make gradle create the fat jar I want.
Or that's not possible and I just need to use the two jars that are given to me?
Thank you for your time.
You can deploy two separate jars behind the same tomcat instance to get the same outcome. Say if you deploy my-first-jar.jar and my-second-jar.jar behind tomcat, you will get two set of endpoints like:
http://localhost:8080/my-first-jar/apis-from-first-jar
http://localhost:8080/my-second-jar/apis-from-second-jar
However, seems like what you are unable to create a fat jar correctly. By default the dependencies of the project are not included in the jar. You need to explicitly say to the build tool(gradle, in your case) to make a fat jar. Have a look here
Once fat jar of Project 1 is created, it will have files from project 2 as well, but you would be able to run only single spring boot app.
PS: You can run multiple apps my combining in a single container application if u wish. Have a look here but wont recommend you to go down that road coz its messy
Related
On looking at the spring-boot-starter-web, spring-boot-starter-security projects on github, i find them to be empty with just a build.gradle file present there.
I hope this is as expected, but this leads me to understand where the actual source code can be found. And I use maven, so I was expecting atleast a pom.xml in these projects. But since it is not present, I am wondering how spring boot team publishes there artifacts to maven central repo.
I hope this is as expected
This is as expected. Spring Boot's starter modules exist purely to being multiple dependencies together into a convenient "package". For example, if you want to write a Servlet-based web application using Spring MVC and Tomcat, a single dependency on spring-boot-starter-web provides all of the dependencies that you need. You can learn a bit more about the starters in the reference documentation.
Where the actual source code can be found
The majority of the code can be found in spring-boot-autoconfigure. For more production-focused features, you'll also find some code in spring-boot-actuator-autoconfigure. The code in these two modules is activated automatically when the dependencies that it requires are on the classpath. You can learn more about this conditional activation and auto-configuration in the reference documentation.
And I use maven, so I was expecting atleast a pom.xml in these projects. But since it is not present, I am wondering how spring boot team publishes there artifacts to maven central repo.
Spring Boot is built with Gradle which, unlike Maven, completely separates the configuration needed by the build system to build the project and the information needed by a build system to consume the project. The build.gradle files provide all of the information that Gradle needs to build the project. As part of this, it generates Gradle module metadata files and Maven pom.xml files that contain all of the information needed to consume the project with Gradle and Maven respectively. These generated files are then published to Maven Central alongside the jar files, source code, etc.
Can someone give me an understanding of what the Spring Boot Maven plugin actually does? I have been Googling, but most of what I find doesn't give a clear picture.
The impression I have so far is that it can create a "fully executable" jar that does not need to be run via java -jar, and that it's also possible to make a more traditional jar that you would run via java -jar. I'm sure there are other variations of what it can produce as well.
I'm also under the impression that it can package up dependencies and resources. It's not at all clear to me how the resources are "accessed" by the application when it's run.
In either of the outcomes described above do I need just the jar and nothing else (i.e. no resource files, dependency jars, etc.)? In other words, is the jar self-contained? When I've opened the jar up, it does seem that everything it needs is there. Is that really the case?
Now, let's go a little further towards what I'm trying to do. I am writing a set of Spring services with REST APIs. Each service will be run in its own VM (or container - future). The services are packaged into a single jar and the service to be used is selected via Spring profile (i.e. spring.profiles.active=a-profile).
The way I've done things like this before has been to use the Maven assembly plugin to produce an archive (zip) for each separate service and inlcude all of the necessities (dependency jars, resource files, etc.). I'd place it where needed, unpack it, tweak some configuration and run it via an included script.
I'm getting the impression that's not "how it's done" when the Spring Boot Maven plugin is involved.
The Spring Boot Maven Plugin provides Spring Boot support in Maven, letting you package executable jar or war archives and run an application “in-place”.
It builds the uber jar which bundles in Tomcat along with your app. If you inspect the contents of the jar with jar -tf <file_name> you will see that the format is a bit different. The Spring Boot classes look normal, but then your project's files are inside a BOOT-INF folder.
I am using Spring Boot 1.4.1 with Gradle 3.1. The module which has the Spring Boot plugin applied creates its own jar with the jar task, and also has the 'fat' jar created with bootRepackage. However, the classes from that module are in BOOT-INF/classes, but I would like them to be in a separate jar in BOOT-INF/lib. How to do this?
EDIT: I know I can move the code to a separate module, but for various reasons I can't make such a split (unless there is no other way). I am looking for a single-module solution, if one exists.
You'll need to set up a multi-project build and move all of your Jersey-related classes into a separate project. You can then depend upon this new project in your Spring Boot project using a project dependency. For example:
dependencies {
compile project(':jersey-endpoints')
}
I have a Maven component service that I package up as a WAR file. I would like to create another Maven project that builds a fully deployable Jetty container with a few custom configurations and contains my component service in it so that I can test my WAR or even deploy it. My questions for this scenario are:
Is it common to want to keep the WAR build separate from the distribution build? My thoughts behind doing this is that someone may not want to use my custom configured Jetty container. Maybe they want to create their own build with Tomcat or something else.
If this is a common thing to do, what packaging type should I use for the custom Jetty container project? It seems weird to me to use JAR or WAR since that isn't the actual artifact that ends up being built. And using "pom" packaging seems equally strange since I was under the impression that that is used for parent projects of submodules.
Ad 1. Yes, this is how I usually structure the project. There is an app project which is a container for application and a separate deploy project to handle the infrastructure. Regardless if it's building a container image, deploy to app server or whatsoever.
You can see it in an example project I've once created for a Devoxx presentation.
Ad 2. Default packaging (hence jar). If all you have in a project is a pom.xml (without any classes), no additional jar will be created nor installed. In the project I've mentioned the pom.xml contains only docker image creation 'logic'. In your scenario it will be jetty related plugin. No additional artifacts will be created.
We are trying to migrate our existing Spring MVC applications to Spring Boot application. Our existing applications are using 3.2.9, so tons of XML configurations. All the beans are defined in the XML files. What we have done is first we have upgraded our existing applications to Spring 4.2.5 version since Spring Boot will work only with Spring 4 versions.
Our requirement is to have both FAT JARs and WAR files from the build. Most of our existing customers would prefer Application Server deployment, so we have to create WAR file for them. Also for our internal testing and new deployments, we are planning to use FAT JARs.
How can we achieve them in the Maven file, we are able to provide separately as below. Is there any maven plug-in to generate both in single build?
<packaging>jar</packaging>
or
<packaging>war</packaging>
We are publishing our artifacts into Nexus repository. So, we want to have the separate repository location for JAR files and WAR files. Can we do that using the single pom.xml file?
Also another question, we have all the XML configurations under WEB-INF folder. When we are moving to the Spring Boot application, it has to be under the resources folder. How can we handle them easily. When we build FAT jars, the resources are not looked under WEB-INF because it simply ignores the webapp project.
I am looking forward for some guidance to complete the migration. Infact, we have already done that changes and it is working fine, but we are confused on this WAR / JAR generations.
Update:
I have got another question in mind, if we are converting our existing applications to spring boot, do we still have to maintain WEB-INF folder in the web-app or can move everything to the resources folder?. While building the WAR file, whether spring boot takes care of moving the resources to WEB-INF? How spring boot would manage to create the WAR file if you are putting all the resources under the resources folder.
Building WAR and FAT JAR is very easy with Gradle.
With Maven, I would try multi module setup, where one sub-module will build fat JAR and second will build WAR file.
Application logic can be as third sub-module and thus being standalone JAR with Spring configuration and beans. This application logic JAR would be as dependency for fat JAR and WAR module.
WAR specific configuration can be placed in Maven WAR sub-module.
I didn't have such requirement before, so don't know what challenges may occur. For sure I wouldn't try to integrate maven-assembly-plugin or other packaging plugins with spring-boot-maven-plugin.
Concerning location of config files, just place them into src/main/resources or it's sub-folders according Spring Boot conventions. Spring Boot is opinionated framework and will be most friendly to you if you don't try to resist defaults.
Maven does not handle this gracefully, but its far from difficult to solve. You can do this with 3 pom files. One parent pom that contains the majority of the configuration, and one each for the packaging portion of the work. This would neatly separate the concerns of the two different assembly patterns too.
To clarify -- I'm not recommending a multi-module configuration here, just multiple poms with names like war-pom.xml and fat-jar-pom.xml, along with parent-pom.xml.