API Gateway Application is no starting after adding SecurityConfig

[imvsaurabh]

Below is my code.
`import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.Customizer;
import org.springframework.security.config.annotation.web.reactive.EnableWebFluxSecurity;
import org.springframework.security.config.web.server.ServerHttpSecurity;
import org.springframework.security.web.server.SecurityWebFilterChain;

@configuration
@EnableWebFluxSecurity
public class SecurityConfig {

@Bean
public SecurityWebFilterChain securityFilterChain(ServerHttpSecurity serverHttpSecurity) {
    serverHttpSecurity.csrf(ServerHttpSecurity.CsrfSpec::disable)
            .authorizeExchange(exchange -> exchange
                    .pathMatchers("/eureka/**")
                    .permitAll()
                    .anyExchange()
                    .authenticated())
            .oauth2ResourceServer(oAuth2ResourceServerSpec -> oAuth2ResourceServerSpec.jwt(Customizer.withDefaults()));

    return serverHttpSecurity.build();
}

}`

`

4.0.0

com.github.imvsaurabh
microservices-parent
1.0-SNAPSHOT

<artifactId>api-gateway</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>api-gateway</name>
<description>api-gateway</description>

<properties>
	<maven.compiler.source>17</maven.compiler.source>
	<maven.compiler.target>17</maven.compiler.target>
</properties>

<dependencies>
	<dependency>
		<groupId>org.springframework.cloud</groupId>
		<artifactId>spring-cloud-starter-gateway-mvc</artifactId>
	</dependency>
	<dependency>
		<groupId>org.springframework.cloud</groupId>
		<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
	</dependency>
	<dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-oauth2-resource-server</artifactId>
	</dependency>
	<dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-security</artifactId>
	</dependency>
	<dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-test</artifactId>
		<scope>test</scope>
	</dependency>
</dependencies>

` `server.port=8080 spring.application.name=api-gateway

eureka.client.service-url.defaultZone=http://localhost:8761/eureka

logging.level.root=INFO
logging.level.org.springframework.cloud.gateway.route.RouteDifinitionLocator=INFO
logging.level.org.springframework.cloud.gateway=TRACE

Product Service Routes

spring.cloud.gateway.mvc.routes[0].id=product-service
spring.cloud.gateway.mvc.routes[0].uri=lb://product-service
spring.cloud.gateway.mvc.routes[0].predicates[0]=Path=/api/product

Order Service Routes

spring.cloud.gateway.mvc.routes[1].id=order-service
spring.cloud.gateway.mvc.routes[1].uri=lb://order-service
spring.cloud.gateway.mvc.routes[1].predicates[0]=Path=/api/order

Discovery Server Routes

spring.cloud.gateway.mvc.routes[2].id=discovery-server
spring.cloud.gateway.mvc.routes[2].uri=http://localhost:8761
spring.cloud.gateway.mvc.routes[2].predicates[0]=Path=/eureka/web
spring.cloud.gateway.mvc.routes[2].filters[0]=SetPath=/

Discovery Server Static Resources Routes

spring.cloud.gateway.mvc.routes[3].id=discovery-server-static
spring.cloud.gateway.mvc.routes[3].uri=http://localhost:8761
spring.cloud.gateway.mvc.routes[3].predicates[0]=Path=/eureka/**

spring.security.oauth2.resourceserver.jwt.issuer-uri=http://localhost:8181/realms/cloud-microservices-realm`
I am getting below error
`2024-01-09T23:49:55.221+05:30 INFO 5272 --- [api-gateway] [ main] c.g.i.apigateway.ApiGatewayApplication : Starting ApiGatewayApplication using Java 17.0.5 with PID 5272 (D:\Development\GitHub\cloud-microservices\api-gateway\target\classes started by saurabh in D:\Development\GitHub\cloud-microservices)
2024-01-09T23:49:55.224+05:30 INFO 5272 --- [api-gateway] [ main] c.g.i.apigateway.ApiGatewayApplication : No active profile set, falling back to 1 default profile: "default"
2024-01-09T23:49:55.788+05:30 WARN 5272 --- [api-gateway] [ main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: java.lang.IllegalStateException: Error processing condition on org.springframework.boot.autoconfigure.context.PropertyPlaceholderAutoConfiguration.propertySourcesPlaceholderConfigurer
2024-01-09T23:49:55.797+05:30 INFO 5272 --- [api-gateway] [ main] .s.b.a.l.ConditionEvaluationReportLogger :

Error starting ApplicationContext. To display the condition evaluation report re-run your application with 'debug' enabled.
2024-01-09T23:49:55.817+05:30 ERROR 5272 --- [api-gateway] [ main] o.s.boot.SpringApplication : Application run failed

java.lang.IllegalStateException: Error processing condition on org.springframework.boot.autoconfigure.context.PropertyPlaceholderAutoConfiguration.propertySourcesPlaceholderConfigurer
at org.springframework.boot.autoconfigure.condition.SpringBootCondition.matches(SpringBootCondition.java:60) ~[spring-boot-autoconfigure-3.2.1.jar:3.2.1]
at org.springframework.context.annotation.ConditionEvaluator.shouldSkip(ConditionEvaluator.java:108) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForBeanMethod(ConfigurationClassBeanDefinitionReader.java:183) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForConfigurationClass(ConfigurationClassBeanDefinitionReader.java:144) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitions(ConfigurationClassBeanDefinitionReader.java:120) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:428) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:289) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:349) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:118) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:789) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:606) ~[spring-context-6.1.2.jar:6.1.2]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:146) ~[spring-boot-3.2.1.jar:3.2.1]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:762) ~[spring-boot-3.2.1.jar:3.2.1]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:464) ~[spring-boot-3.2.1.jar:3.2.1]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:334) ~[spring-boot-3.2.1.jar:3.2.1]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1358) ~[spring-boot-3.2.1.jar:3.2.1]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1347) ~[spring-boot-3.2.1.jar:3.2.1]
at com.github.imvsaurabh.apigateway.ApiGatewayApplication.main(ApiGatewayApplication.java:12) ~[classes/:na]
Caused by: java.lang.IllegalStateException: Failed to introspect Class [org.springframework.security.config.annotation.web.reactive.ServerHttpSecurityConfiguration] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@1d44bcfa]
at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:483) ~[spring-core-6.1.2.jar:6.1.2]
at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:360) ~[spring-core-6.1.2.jar:6.1.2]
at org.springframework.util.ReflectionUtils.getUniqueDeclaredMethods(ReflectionUtils.java:417) ~[spring-core-6.1.2.jar:6.1.2]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.lambda$getTypeForFactoryMethod$1(AbstractAutowireCapableBeanFactory.java:749) ~[spring-beans-6.1.2.jar:6.1.2]
at java.base/java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1708) ~[na:na]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getTypeForFactoryMethod(AbstractAutowireCapableBeanFactory.java:748) ~[spring-beans-6.1.2.jar:6.1.2]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineTargetType(AbstractAutowireCapableBeanFactory.java:681) ~[spring-beans-6.1.2.jar:6.1.2]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:652) ~[spring-beans-6.1.2.jar:6.1.2]
at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1644) ~[spring-beans-6.1.2.jar:6.1.2]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doGetBeanNamesForType(DefaultListableBeanFactory.java:562) ~[spring-beans-6.1.2.jar:6.1.2]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:534) ~[spring-beans-6.1.2.jar:6.1.2]
at org.springframework.boot.autoconfigure.condition.OnBeanCondition.collectBeanNamesForType(OnBeanCondition.java:247) ~[spring-boot-autoconfigure-3.2.1.jar:3.2.1]
at org.springframework.boot.autoconfigure.condition.OnBeanCondition.getBeanNamesForType(OnBeanCondition.java:240) ~[spring-boot-autoconfigure-3.2.1.jar:3.2.1]
at org.springframework.boot.autoconfigure.condition.OnBeanCondition.getBeanNamesForType(OnBeanCondition.java:230) ~[spring-boot-autoconfigure-3.2.1.jar:3.2.1]
at org.springframework.boot.autoconfigure.condition.OnBeanCondition.getMatchingBeans(OnBeanCondition.java:183) ~[spring-boot-autoconfigure-3.2.1.jar:3.2.1]
at org.springframework.boot.autoconfigure.condition.OnBeanCondition.getMatchOutcome(OnBeanCondition.java:158) ~[spring-boot-autoconfigure-3.2.1.jar:3.2.1]
at org.springframework.boot.autoconfigure.condition.SpringBootCondition.matches(SpringBootCondition.java:47) ~[spring-boot-autoconfigure-3.2.1.jar:3.2.1]
... 17 common frames omitted
Caused by: java.lang.NoClassDefFoundError: org/springframework/web/reactive/config/WebFluxConfigurer
at java.base/java.lang.Class.getDeclaredMethods0(Native Method) ~[na:na]
at java.base/java.lang.Class.privateGetDeclaredMethods(Class.java:3402) ~[na:na]
at java.base/java.lang.Class.getDeclaredMethods(Class.java:2504) ~[na:na]
at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:465) ~[spring-core-6.1.2.jar:6.1.2]
... 33 common frames omitted
Caused by: java.lang.ClassNotFoundException: org.springframework.web.reactive.config.WebFluxConfigurer
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641) ~[na:na]
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188) ~[na:na]
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520) ~[na:na]
... 37 common frames omitted
`

Can anyone please help me resolve this issue.

[SaiUpadhyayula]

ClassNotFound generally means that there is a mismatch in a dependency version.

Make sure you have the same code as the GitHub repo, and delete your .m2/repository folder, in this way, maven re-downloads the dependencies and it should work.