I am trying to understand the difference between spring boot and spring boot web. From this boot tutorial the pom contains spring boot as the parent and spring boot web as a dependency like so:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.3.1.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
What are the uses for the 2 different versions? Do you always use them together? This spring boot documentation tells me if the program is production ready to use:
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
But if that's the case then why isn't there one for web like so:
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web-actuator</artifactId>
</dependency>
</dependencies>
There are lots of these different 'starter' poms for spring boot. Each one of them tells maven to bring in the dependencies needed for that particular functionality. So spring-boot-starter-web brings in all the stuff needed for MVC and autoconfigures it with sensible defaults. The real trick to spring boot is it when it autoconfigures things it uses a whole of #ConditionalOnClass or other such annotations that look at what dependencies are on the classpath and provides configuration for those dependencies. What this means is when you have that spring boot actuator starter, when it's doing its autoconfiguration it will look at what other spring boot start poms you have in your pom.xml and it will configure different endpoints for the actuator so you can see the various metrics the actuator provides for that particular module.
Spring Boot is a framework, spring-boot-starter-web is one of the packages that comes with it, a jar file.
Just like JDK is a library, and util is one of the packages included in the JDK.
From: https://docs.spring.io
Spring Boot provides a number of “Starters” that auto-configures your application adds jars to your classpath. The spring-boot-starter-parent is a core starter that provides useful maven defaults. It also provides a dependency-management section so that if you import additional starters then you can omit version tags for “blessed” dependencies. Therefore you should only need to specify the Spring Boot version number on this dependency
Starters are a set of convenient dependency descriptors that you can include in your application considering each starter covers a specific area.The starters contain a lot of the dependencies that you need to get a project up and running quickly and with a consistent, supported set of managed transitive dependencies.For example, if you want to get started using Spring and JPA for database access, just include the "spring-boot-starter-data-jpa" dependency in your project, and you are good to go.
Spring Boot
spring-boot-starter-web is starter for building web, including RESTful, applications using Spring MVC. It uses Tomcat as the default embedded container
Spring Boot has different groups of starters like
1-Spring Boot application starters: spring-boot-starter-web , spring-boot-starter-jdbc , spring-boot-starter-jpa etc
2-Spring Boot production starters : spring-boot-starter-actuator which provides production ready features to help you monitor and manage your application
3-Spring Boot technical starters: spring-boot-starter-jetty , spring-boot-starter-tomcat these starters can be used to exclude or swap specific technical facets
1.spring-boot-starter-parent deals with the auto start of main method and run methods so on..
2.and spring-boot-starter-web deals with the spring MVC things like controller, autowired so on.. Hope this helps..
Spring boot is a very cool tool of Spring Source. In many conference the team talck about of Spring Boot as one of the three DSR(Domain Specific Run-Time) of Pivotal.... Spring Boot, Spring XD and Grails(now Pivotal didn't support Groovy & Grails).
That said compare Spring boot stand alone and Spring boot web enviroment may be a cool conversation. First of all Spring boot give you many production ready istruments such as actuator(avaiable whit sprin boot in web enviroment), spring remote shall and so on. The main difference is the same of had a spring stand-alone context or a Spring web context. Of course some of the potentiality that yon could have are avaiable in a web context, Actuator is an example. but the main difference is in what kind of application you need, web or stand-alone.
Related
When I start to learn the spring-webflux, I have the question about this component.
I built a simple project, using maven to manage it. I addded the dependencies related to spring-boot-starter-web and spring-boot-starter-webflux, like :
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-webflux</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
But it doesn't work. When removing the spring-boot-starter-web dependency, it can work well.
As explained in the Spring Boot reference documentation section about the web environment, adding both web and webflux starters will configure a Spring MVC web application.
This is behaving like that, because many existing Spring Boot web applications (using MVC) will depend on the webflux starter to use the WebClient. Spring MVC partially support reactive return types, so this is an expected use case. The opposite isn't really true, since a reactive application is not really likely to use Spring MVC bits.
So using both web and webflux starters is supported, but it will configure a Spring MVC application. You can always force the Spring Boot application to be reactive with:
SpringApplication.setWebApplicationType(WebApplicationType.REACTIVE)
But it's still a good idea to clean up dependencies as it would be easy to use a blocking feature in your reactive web application.
I had a similar issue using spring-boot-starter-webflux and spring-data-geode causing
DEBUG [http-nio-8082-exec-2] org.sprin.web.servl.resou.ResourceHttpRequestHandler 454 handleRequest: Resource not found
It was resolved by changing the application type
#SpringBootApplication
public class Web {
public static void main(String[] args) {
SpringApplication app = new SpringApplication(Web.class);
app.setWebApplicationType(WebApplicationType.REACTIVE);
SpringApplication.run(Web.class, args);
}
}
The whole class looks like this
After setting the application type, if I don't then call the SpringApplication in a static way, I get this:
I have a Spring Boot RESTful microservice that a customer would like to nest inside their Spring Boot application.
Could someone tell me whether this is possible?
I was hoping this would be as simple as adding a dependency on my application in the customers maven pom file and then excluding the tomcat dependency since the customer already uses the embedded tomcat.
Thanks,
Ben
Since they already use Spring Boot to start their app, you can simply mark all Spring Boot dependencies as provided in your Maven POM, this would exclude it from the JAR as well as embedded Tomcat and all related dependencies. Also make sure you don't build your JAR as a Spring Boot executable (should be the default if you're not using the spring-boot-maven-plugin).
On the customer side, they would need to include your JAR as a dependency, and possibly add a scanBasePackages property to their #SpringBootApplication, to auto-discover your application classes, if they don't reside in a package under the one that #springBootApplication is on. Also, they'll need to be mindful of any URI collisions between your app and theirs, as the two will be sharing the same environment.
I am trying to make a filedownload endpoint for my ftp server. I see that there is a Spring boot integration starter module for Spring boot but this module doesen't contain classes like DefaultFtpSessionFactory . I've read on the web that there are other modules available like Spring integration http and Spring integration ftp. However, these are not spring boot modules. Is it save to include those modules in my POM anyway? Or shoulden't I use Spring boot starter integration in the first place?
I see in this example: https://blog.pavelsklenar.com/spring-integration-sftp-upload-example/ That the author is using spring boot next to Spring Integration 4.3.8 regular Spring. He does say those are managed by Spring boot but i'm not exactly sure what he means by that.
Can anyone tell me what modules I should include if I want to make the download function? Thanks
Since it's unlikely that an application would require all Spring Integration modules (ftp, sftp, http, mqtt, ... etc), the starter only includes the core and java dsl jars on the classpath (in Spring Integration 5.0, the DSL is built in so boot 2.0 only includes the core jar).
Otherwise, you'd end up with many jars on the classpath that you don't need.
So, yes, you have to manually add the dependencies you need...
<dependency>
<groupId>org.springframework.integration</groupId>
<artifactId>spring-integration-ftp</artifactId>
</dependency>
Note that you don't need a <version/> - boot will manage that for you and bring in the right version corresponding to the core.
The modules themselves will bring in any additional transitive dependencies they need. So you just need to add the top level module(s) to your pom.
I'm trying to in corporate Spring Actuator to my application. I have added the dependency in my pom.xml:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
<version>1.4.2.RELEASE</version>
</dependency>
But I get a 404 when trying to access the /health endpoint. After looking online, I've read that I need to also have the spring-boot-starter-web dependency in my POM. I was under the assumption that I only need the actuator dependency in order to get it working
Yes web is needed if you want to access via HTTP (otherwise only JMX is available).
The documentation for actuator states
"Click Dependencies and select Spring Web and Spring Boot Actuator."
I am currently working with Spring Boot with a number of starter packs, such as the web MVC framework, Thymeleaf templates and security.
Each of these packages have a lot of different configuration options. I have mainly been using the source from the Auto-configuration package to figure out which beans need to be wired up and how to do that.
However, Is there any easy way to find a list of expected beans/classes that are needed by a given Spring package?
To view the beans you can you spring boot actuator
To Enable actuator, you can simply add the actuator starter dependency to your project.
For Gradle
compile("'org.springframework.boot:spring-boot-starter-actuator:1.3.1.RELEASE'
")
For Maven
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
<version>1.3.1.RELEASE</version>
</dependency>
You can skip the version if you are using spring boot parent pom
Now you can rebuild your application make get request to http://server:port/beans if local and port is 8080 then
http://localhost:8080/beans
If you want to access using CURL command line tool you can
curl http://localhost:8080/beans
For more information visit
http://docs.spring.io/spring-boot/docs/current/reference/html/production-ready-endpoints.html