springboot rest swagger :error in initialising bean - rest

Question

I am using swagger to document my spring boot rest application
Using
spring-boot-starter-web
spring-boot-starter-data-rest
springfox-swagger2 2.9.2
springfox-swagger 2.9.2
Code is building fine but when I run it it is throwing error below
org.springframework.beans.factory.UnsatisfiedDependencyException:
Error creating bean with name 'requestMappingHandlerMapping' defined in class path resource [org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration
$EnableWebMvcConfiguration.class]:
Unsatisfied dependency expressed through method 'requestMappingHandlerMapping' parameter 1;
nested exception is org.springframework.beans.factory.BeanCreationException:
Error creating bean with name 'mvcConversionService' defined in class path resource [org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration
$EnableWebMvcConfiguration.class]:
Bean instantiation via factory method failed;
nested exception is org.springframework.beans.BeanInstantiationException:
Failed to instantiate [org.springframework.format.support.FormattingConversionService]:
Factory method 'mvcConversionService' threw exception;
nested exception is org.springframework.beans.factory.BeanCreationException:
Error creating bean with name 'jsonSchemaConverter' defined in class path resource [org/springframework/data/rest/webmvc/config/RepositoryRestMvcConfiguration.class]:
Bean instantiation via factory method failed;
nested exception is org.springframework.beans.BeanInstantiationException:
Failed to instantiate [org.springframework.data.rest.webmvc.json.PersistentEntityToJsonSchemaConverter]:
Factory method 'jsonSchemaConverter' threw exception;
nested exception is org.springframework.beans.factory.BeanCreationException:
Error creating bean with name 'defaultConversionService' defined in class path resource [org/springframework/data/rest/webmvc/config/RepositoryRestMvcConfiguration.class]:
Bean instantiation via factory method failed;
nested exception is org.springframework.beans.BeanInstantiationException:
Failed to instantiate [org.springframework.format.support.DefaultFormattingConversionService]:
Factory method 'defaultConversionService' threw exception;
nested exception is org.springframework.beans.factory.BeanCreationException:
Error creating bean with name 'repositoryInvokerFactory' defined in class path resource [org/springframework/data/rest/webmvc/config/RepositoryRestMvcConfiguration.class]:
Bean instantiation via factory method failed;
nested exception is org.springframework.beans.BeanInstantiationException:
nested exception is org.springframework.beans.BeanInstantiationException:
Failed to instantiate [org.springframework.data.repository.support.RepositoryInvokerFactory]:
Factory method 'repositoryInvokerFactory' threw exception;
nested exception is java.lang.NoSuchMethodError: org.springframework.plugin.core.PluginRegistry.of(Ljava/util/List;)Lorg/springframework/plugin/core/PluginRegistry;

Answer 1

I had the same problem. Here is my fix:
TL/DR:
Springfox uses an outdated version of spring-plugin-core and is incompatible with spring boot 2.2.5. Springfox seems to be no longer maintained; migrate to a different spring-swagger-bridge, such as Springdoc-openapi: https://springdoc.github.io/springdoc-openapi-demos/
Relevant output
nested exception is org.springframework.beans.BeanInstantiationException:
Failed to instantiate [org.springframework.data.repository.support.RepositoryInvokerFactory]:
Factory method 'repositoryInvokerFactory' threw exception; nested exception is java.lang.NoSuchMethodError:
'org.springframework.plugin.core.PluginRegistry org.springframework.plugin.core.PluginRegistry.of(java.util.List)'
From NoSuchMethodError: org.springframework.plugin.core.PluginRegistry.getPluginOrDefaultFor:
...a wild guess would be that the last working version of springfox (working for you and us) was compiled with a Spring boot version inferior to 2.2.2. That boot version had a different method signature for getPluginOrDefaultFor (or possibly the method didn't exist at all).
Cause
springfox imports version 1.2.0 of the spring-plugin-core. Spring Boot 2.2.5 needs version 2.0.0.RELEASE
springfox wins the import lottery; test fails b/c Spring Boot can't find its method.
explicitly importing 2.0.0.RELEASE makes springfox die.
springfox' latest version is 2.9.2; even the 3.0.0-SNAPSHOT does not fix the issue: https://github.com/springfox/springfox/issues/2932
Solution
Springfox is apparently abandoned:
Springfox swagger not working in spring boot 2.2.0
Solution is to migrate to a different spring-swagger bridge.
Most likely candidate is Springdoc-openapi:
https://springdoc.github.io/springdoc-openapi-demos/
User experience (last comment from https://github.com/springfox/springfox/issues/2932):
Yes I ended up following the links to 'springDoc' and found a
quick tutorial.
It was super easy to setup all in the pom.xml file.
Just one tweak was needed
<!-- org.springdoc for swagger setup -->
<dependency>
<groupId>org.springdoc</groupId>
<artifactId>springdoc-openapi-core</artifactId>
<version>1.1.49</version>
<exclusions>
<exclusion>
<groupId>io.github.classgraph</groupId>
<artifactId>classgraph</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springdoc</groupId>
<artifactId>springdoc-openapi-ui</artifactId>
<version>1.1.49</version>
</dependency>