Clone of start.spring.io

I'm trying to build an instance of start.spring.io to use it in an air-gaped network. I have been working on it for three weeks and still I don't understand well what to do. I have cloned start.spring.io from GitHub in a host connected to Internet.

There I can build the application without errors:

./mvnw clean install -DskipTests=true

Then if I true to run the application (../mwnw spring-boot:run from the start-site directory), I get the following error when the application starts, I mean is not an error trying to generate a project, and the application dies:

2022-12-19 17:53:21.170  INFO 2701 --- [  restartedMain] o.s.b.a.w.s.WelcomePageHandlerMapping    : Adding welcome page: class path resource [static/index.html]
2022-12-19 17:53:21.264  WARN 2701 --- [  restartedMain] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerMapping' defined in class path resource [org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration$EnableWebMvcConfiguration.class]: Invocation of init method failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [io.spring.initializr.web.controller.ProjectGenerationController] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@5cb0d902]
2022-12-19 17:53:21.272  INFO 2701 --- [  restartedMain] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2022-12-19 17:53:21.311  INFO 2701 --- [  restartedMain] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2022-12-19 17:53:21.411 ERROR 2701 --- [  restartedMain] o.s.boot.SpringApplication               : Application run failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerMapping' defined in class path resource [org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration$EnableWebMvcConfiguration.class]: Invocation of init method failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [io.spring.initializr.web.controller.ProjectGenerationController] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@5cb0d902]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1804) ~[spring-beans-5.3.23.jar:5.3.23]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:620) ~[spring-beans-5.3.23.jar:5.3.23]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.23.jar:5.3.23]
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$
...

So, I am not adding any special dependencies or initilializr dependencies other than those already included in the project. I use Java 17 from Bell Soft. I am not about the Spring Boot version but I haven't modified anything in the project. The pom file in the top directory includes:

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.5</version>
    </parent>

About my dependencies I am using the initializer-bom:0.20.0-SNAPSHOT. I have also tried with other versions like 0.13.0 and 0.12.0 but the build fails in both cases for the start-site:

[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR : 
[INFO] -------------------------------------------------------------
[ERROR] /workspaces/start.spring.io.ori/start-site/src/main/java/io/spring/start/site/extension/dependency/springcloud/SpringCloudContractKotlinDslGradleBuildCustomizer.java:[44,22] cannot find symbol
  symbol:   method snippets()
  location: variable build of type io.spring.initializr.generator.buildsystem.gradle.GradleBuild
[ERROR] /workspaces/start.spring.io.ori/start-site/src/main/java/io/spring/start/site/extension/dependency/graalvm/HibernatePluginGroovyDslGradleBuildCustomizer.java:[39,22] cannot find symbol
  symbol:   method snippets()
  location: variable build of type io.spring.initializr.generator.buildsystem.gradle.GradleBuild
[ERROR] /workspaces/start.spring.io.ori/start-site/src/main/java/io/spring/start/site/extension/dependency/springcloud/SpringCloudContractGroovyDslGradleBuildCustomizer.java:[36,22] cannot find symbol
  symbol:   method snippets()
  location: variable build of type io.spring.initializr.generator.buildsystem.gradle.GradleBuild
[INFO] 3 errors

I wonder if this effort makes sense. If I manage to build the application, will I be able of generating code or does the application connect to somewhere else to retrieve the data required to generate the code?
I would appreciate any hints. Thanks

Solution

I will write my (potential) answer here, even though I don't really think that is a real answer but too big to make it as a comment.

My setup:

Amazon Coretto JDK 17 https://docs.aws.amazon.com/corretto/latest/corretto-17-ug/downloads-list.html (it is not JDK 17 from Bell Soft)
Windows 11 Home

So I went to https://github.com/spring-io/start.spring.io and cloned it.

git clone https://github.com/spring-io/start.spring.io.git

Then I went in the root directoy of the cloned project and ran following command:

./mvnw clean install

Here I got some errors while running the tests, but this shouldn't be way too tragic - I think they failed for me, because it tries to run some gradlew commands but they do fail, because I don't have Gradle installed on my PC, as I am always using the Gradle Wrapper.

Then I started the Spring Boot Application.

cd start-site
../mvnw spring-boot:run

The Spring Boot Application started:

022-12-20T15:01:03.510+01:00  INFO 16592 --- [  restartedMain] io.spring.start.site.StartApplication    : No active profile set, falling back to 1 default profile: "default"
2022-12-20T15:01:03.573+01:00  INFO 16592 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
2022-12-20T15:01:03.573+01:00  INFO 16592 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'
2022-12-20T15:01:04.800+01:00  INFO 16592 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
2022-12-20T15:01:04.809+01:00  INFO 16592 --- [  restartedMain] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2022-12-20T15:01:04.810+01:00  INFO 16592 --- [  restartedMain] o.apache.catalina.core.StandardEngine    : Starting Servlet engine: [Apache Tomcat/10.1.1]
2022-12-20T15:01:04.872+01:00  INFO 16592 --- [  restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2022-12-20T15:01:04.873+01:00  INFO 16592 --- [  restartedMain] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1298 ms
2022-12-20T15:01:05.371+01:00  INFO 16592 --- [  restartedMain] o.s.b.a.w.s.WelcomePageHandlerMapping    : Adding welcome page: class path resource [static/index.html]
2022-12-20T15:01:05.823+01:00  INFO 16592 --- [  restartedMain] org.ehcache.core.EhcacheManager          : Cache 'initializr.metadata' created in EhcacheManager.
2022-12-20T15:01:05.832+01:00  INFO 16592 --- [  restartedMain] org.ehcache.jsr107.Eh107CacheManager     : Registering Ehcache MBean javax.cache:type=CacheConfiguration,CacheManager=urn.X-ehcache.jsr107-default-config,Cache=initializr.metadata
2022-12-20T15:01:05.832+01:00  INFO 16592 --- [  restartedMain] org.ehcache.jsr107.Eh107CacheManager     : Registering Ehcache MBean javax.cache:type=CacheStatistics,CacheManager=urn.X-ehcache.jsr107-default-config,Cache=initializr.metadata
2022-12-20T15:01:05.835+01:00  INFO 16592 --- [  restartedMain] org.ehcache.core.EhcacheManager          : Cache 'initializr.dependency-metadata' created in EhcacheManager.
2022-12-20T15:01:05.836+01:00  INFO 16592 --- [  restartedMain] org.ehcache.jsr107.Eh107CacheManager     : Registering Ehcache MBean javax.cache:type=CacheConfiguration,CacheManager=urn.X-ehcache.jsr107-default-config,Cache=initializr.dependency-metadata
2022-12-20T15:01:05.836+01:00  INFO 16592 --- [  restartedMain] org.ehcache.jsr107.Eh107CacheManager     : Registering Ehcache MBean javax.cache:type=CacheStatistics,CacheManager=urn.X-ehcache.jsr107-default-config,Cache=initializr.dependency-metadata
2022-12-20T15:01:05.839+01:00  INFO 16592 --- [  restartedMain] org.ehcache.core.EhcacheManager          : Cache 'initializr.project-resources' created in EhcacheManager.
2022-12-20T15:01:05.841+01:00  INFO 16592 --- [  restartedMain] org.ehcache.jsr107.Eh107CacheManager     : Registering Ehcache MBean javax.cache:type=CacheConfiguration,CacheManager=urn.X-ehcache.jsr107-default-config,Cache=initializr.project-resources
2022-12-20T15:01:05.841+01:00  INFO 16592 --- [  restartedMain] org.ehcache.jsr107.Eh107CacheManager     : Registering Ehcache MBean javax.cache:type=CacheStatistics,CacheManager=urn.X-ehcache.jsr107-default-config,Cache=initializr.project-resources
2022-12-20T15:01:05.843+01:00  INFO 16592 --- [  restartedMain] org.ehcache.core.EhcacheManager          : Cache 'initializr.templates' created in EhcacheManager.
2022-12-20T15:01:05.843+01:00  INFO 16592 --- [  restartedMain] org.ehcache.jsr107.Eh107CacheManager     : Registering Ehcache MBean javax.cache:type=CacheConfiguration,CacheManager=urn.X-ehcache.jsr107-default-config,Cache=initializr.templates
2022-12-20T15:01:05.844+01:00  INFO 16592 --- [  restartedMain] org.ehcache.jsr107.Eh107CacheManager     : Registering Ehcache MBean javax.cache:type=CacheStatistics,CacheManager=urn.X-ehcache.jsr107-default-config,Cache=initializr.templates
2022-12-20T15:01:06.026+01:00  INFO 16592 --- [  restartedMain] o.s.b.d.a.OptionalLiveReloadServer       : LiveReload server is running on port 35729
2022-12-20T15:01:06.031+01:00  INFO 16592 --- [  restartedMain] o.s.b.a.e.web.EndpointLinksResolver      : Exposing 2 endpoint(s) beneath base path '/actuator'
2022-12-20T15:01:06.078+01:00  INFO 16592 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8080 (http) with context path ''
2022-12-20T15:01:06.089+01:00  INFO 16592 --- [  restartedMain] io.spring.start.site.StartApplication    : Started StartApplication in 3.056 seconds (process running for 3.444)
2022-12-20T15:01:17.890+01:00  INFO 16592 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring DispatcherServlet 'dispatcherServlet'
2022-12-20T15:01:17.891+01:00  INFO 16592 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : Initializing Servlet 'dispatcherServlet'
2022-12-20T15:01:17.892+01:00  INFO 16592 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : Completed initialization in 1 ms
2022-12-20T15:01:18.122+01:00  INFO 16592 --- [io-8080-exec-10] .s.SaganInitializrMetadataUpdateStrategy : Fetching Spring Boot metadata from https://spring.io/project_metadata/spring-boot

If I now call http://localhost:8080/ - it works, I didn't do absolutely nothing.

Could it maybe be your JDK? I mean the JDKs are similar but not the same... And you also asked:

I wonder if this effort makes sense. If I manage to build the application, will I be able of generating code or does the application connect to somewhere else to retrieve the data required to generate the code? I would appreciate any hints. Thanks

I personally think, it could make sense but - as soon as I generated a project on my own Spring Initializr, I watched the console of the Spring Boot Application and could see the following log:

Fetching Spring Boot metadata from https://spring.io/project_metadata/spring-boot

So it looks, like this thing actually fetches data from the internet, now I don't know what options you have but I have two in mind.

You could try to fork the GitHub Project and try to remove this network call (if this is really the only one) - I couldn't see anything more in the logs atleast... The actual response of the Call looks pretty simple though:

{"id":"spring-boot","name":"Spring Boot","projectReleases":[{"version":"3.0.1-SNAPSHOT","versionDisplayName":"3.0.1-SNAPSHOT","current":false,"releaseStatus":"SNAPSHOT","snapshot":true},{"version":"3.0.0","versionDisplayName":"3.0.0","current":true,"releaseStatus":"GENERAL_AVAILABILITY","snapshot":false},{"version":"2.7.7-SNAPSHOT","versionDisplayName":"2.7.7-SNAPSHOT","current":false,"releaseStatus":"SNAPSHOT","snapshot":true},{"version":"2.7.6","versionDisplayName":"2.7.6","current":false,"releaseStatus":"GENERAL_AVAILABILITY","snapshot":false},{"version":"2.6.14","versionDisplayName":"2.6.14","current":false,"releaseStatus":"GENERAL_AVAILABILITY","snapshot":false},{"version":"2.5.14","versionDisplayName":"2.5.14","current":false,"releaseStatus":"GENERAL_AVAILABILITY","snapshot":false},{"version":"2.4.13","versionDisplayName":"2.4.13","current":false,"releaseStatus":"GENERAL_AVAILABILITY","snapshot":false}]}

You allow explicitly the URL https://spring.io/project_metadata/spring-boot to fetch data inside of your Air Gap Network (I don't know if this is viable though)

I hope this helps a bit?