Spring WS annotated endpoint - spring

I have to replace the deprecated class AbstractMarshallingPayloadEndpoint from springws 2.0. which my class was extending and overriding the invokeInternal method as below.
Example :
public class UpdateUserEndpoint extends AbstractMarshallingPayloadEndpoint {
#Override
protected Object invokeInternal(Object request){
//MY BUSINESS LOGIC here.
}
}
I am trying to replace my class with endpoint annotation.
#PayloadRoot(localPart = "MyRequest", namespace = "MyNamespace")
public MyResponse updateUser(MyRequest request) { ... }
I am ending up with exception while the server startup with a BeanCreationException:
I use Castor marshaller and unmarshaller in mapping.
Need some thoughts to proceed in a right way.

Related

Inject Spring Bean in Jackson VirtualBeanPropertyWriter

tldr; I want to add virtual fields while serializing the JPA entity into JSON using Jackson #JsonAppend. The value of the virtual fields must be determined via service managed by Spring. How do I inject my spring-managed service inside a Jackson class?
Technologies: Spring Boot 1.5.10, Spring Data Rest, JPA 2.1, Jackson 2.8.10
Details:
I have a Spring Data managed JPA entity:
#Entity
public class Stream {
...
}
I created a Custom Jackson module with a Mixin to add #JsonAppend virtual field as below:
#Bean
public Module customModule() {
return new CustomModule();
}
#Component
class CustomModule extends SimpleModule {
CustomModule() {
setMixInAnnotation(Stream.class, StreamMixin.class);
}
#JsonAppend(
props = {
#JsonAppend.Prop(name = "canEdit", value = ABACInspector.class)
}
)
abstract class StreamMixin {}
}
The ABACInspector class extends Jackson's VirtualBeanPropertyWriter to determine the value of the virtual field canEdit. If this class does not use a Spring service (sets hard-coded value for example), it works fine and the field shows up in REST API JSON response. But autowiring a Spring bean doesn't work and the object remains null.
#Component
class ABACInspector extends VirtualBeanPropertyWriter {
#Autowired
private PermissionEvaluator permissionEvaluator;
public ABACInspector() {
}
public ABACInspector(BeanPropertyDefinition propDef, Annotations contextAnnotations, JavaType declaredType) {
super(propDef, contextAnnotations, declaredType);
}
#Override
protected Object value(Object bean, JsonGenerator gen, SerializerProvider prov) throws Exception {
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
boolean permission = permissionEvaluator.hasPermission(authentication, bean, Action.STREAM_VIEW);
System.out.println("evaluated permission is " + permission);
return permission;
}
#Override
public VirtualBeanPropertyWriter withConfig(MapperConfig<?> config, AnnotatedClass declaringClass, BeanPropertyDefinition propDef, JavaType type) {
return new ABACInspector(propDef, null, type);
}
}
Below is the NPE error (because permissionEvaluator is never injected):
{"status":"INTERNAL_SERVER_ERROR","message":"Could not write JSON:
(was java.lang.NullPointerException); nested exception is com.fasterxml.jackson.databind.JsonMappingException:
(was java.lang.NullPointerException) (through reference chain: org.springframework.data.rest.webmvc.json.PersistentEntityJackson2Module$PersistentEntityResourceSerializer$1[\"content\"]->com.example.streammanagement.Stream[\"canView\"])"
I am aware of Spring Data Rest's HalHandlerInstantiator that contains the AutowireCapableBeanFactory but I am not sure how/if that can help here. Refer DATAREST-840
Jackson internally calls withConfig function of your component to build VirtualBeanPropertyWriter.
So if you use breakpoints, you can see that first a component with injected bean is created, then withConfig function is called and new VirtualBeanPropertyWriter object is created which is used by jackson and of course does not have the injected bin (since you called the constructor manually).
So you can change it by this way:
#Component
class ABACInspector extends VirtualBeanPropertyWriter {
private PermissionEvaluator permissionEvaluator;
#Autowired
public ABACInspector(PermissionEvaluator permissionEvaluator) {
this.permissionEvaluator = permissionEvaluator;
}
public ABACInspector(BeanPropertyDefinition propDef, Annotations contextAnnotations, JavaType declaredType, PermissionEvaluator permissionEvaluator) {
super(propDef, contextAnnotations, declaredType);
this.permissionEvaluator = permissionEvaluator;
}
#Override
protected Object value(Object bean, JsonGenerator gen, SerializerProvider prov) throws Exception {
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
boolean permission = permissionEvaluator.hasPermission(authentication, bean, Action.STREAM_VIEW);
System.out.println("evaluated permission is " + permission);
return permission;
}
#Override
public VirtualBeanPropertyWriter withConfig(MapperConfig<?> config, AnnotatedClass declaringClass, BeanPropertyDefinition propDef, JavaType type) {
return new ABACInspector(propDef, null, type, permissionEvaluator);
}
}

Dynamic Proxy Bean with Autowiring capability

In a spring based project I am working on, there's a layer of functionality for calling web service. For each web service operation, a method is created with almost same code but with some different, operation specific, information(e.g. service name, operation name, namespaces, etc).
I am replacing this layer with interfaces and annotated methods. For example, below code is provided for operation "fetchBar" of web service("foo").
package a.b.c.webservices;
#WebService(service="foo", namespace="...")
public interface FooWebService {
#WebServiceOperation(operation="fetchBar")
BarRespons fetchBar(BarRequest request) throws WebServiceException;
}
Now I want, with some mechanism, spring allow me to create dynamic proxy beans from some specified package(s) and I can use following code to call web service.
package a.b.c.business;
import a.b.c.webservices.FooWebService;
public class FooBusiness {
#Autowired
FooWebService fooWebService;
public Bar getBar() {
Bar bar = null;
BarRequest request;
//create request
BarResponse response = fooWebService.fetchBar(request);
//extrac bar from response
return bar;
}
}
To achieve this I have created dynamic beans instances using java.lang.reflect.Proxy.newProxyInstance by providing it implementation of InvocationHandler. But Autowiring doesn't work in provided implementation of invocationHandler and in its further dependencies.
I tried following ways to achieve this.
Implemented BeanFactoryPostProcessor.postProcessBeanFactory and registered beans using ConfigurableListableBeanFactory.registerSingleton method.
Implemented ImportBeanDefinitionRegistrar.registerBeanDefinitions and tried to use BeanDefinitionRegistry.registerBeanDefinition but I am confused how to provide correct Bean definition that supports Autowiring.
Can any one tell me what is missing? Please guide me if I am not going in right direction.
Here's how I implemented all the functionality that creates beans of 'WebService' annotated interfaces and also supports Autowiring inside proxy implementation. (package declaration and import statements are omitted in below code)
First of all I created WebService and WebServiceOperation annotation.
WebService Annotation
#Target(ElementType.TYPE)
#Retention(RetentionPolicy.RUNTIME)
public #interface WebService {
String service();
String namespace();
}
WebService Operation Annotation
#Target(ElementType.METHOD)
#Retention(RetentionPolicy.RUNTIME)
public #interface WebServiceOperation {
String operation();
}
Next step is to scan all WebService annotated interfaces from specified packages. Spring provides ClassPathScanningCandidateComponentProvider for package scanning but it does not detect interfaces. Please see this question and it's answer for more details. So I extended ClassPathScanningCandidateComponentProvider and overrode isCandidateComponent method.
ClassPathScanner
public class ClassPathScanner extends ClassPathScanningCandidateComponentProvider {
public ClassPathScanner(final boolean useDefaultFilters) {
super(useDefaultFilters);
}
#Override
protected boolean isCandidateComponent(AnnotatedBeanDefinition beanDefinition) {
return beanDefinition.getMetadata().isIndependent();
}
}
At this point I created EnableWebServices annotation to enable web services and to provide web service packages that contain WebService annotated interfaces.
EnableWebServices Annotation
#Retention(RetentionPolicy.RUNTIME)
#Target(ElementType.TYPE)
#Import({
WebServiceProxyConfig.class,
WebServiceProxyBeansRegistrar.class
})
public #interface EnableWebServices {
#AliasFor("basePackages")
String[] value() default {};
#AliasFor("value")
String[] basePackages() default {};
}
This annotation can be applied to some Configuration annotated class with packages to scan interfaces, as below.
#EnableWebServices({
"a.b.c.webservices",
"x.y.z.webservices"
})
It's time to think about dynamic proxy creation that will invoke actual web service from information given in WebService and WebServiceOperation annotations. Java provides a mechanism to create dynamic proxy which requires to provide implementation of InvocationHandler interface and provide logic in its invoke method. I named this implementaiton as WebServiceProxy
Suppose a bean of type 'TheWebServiceCaller' contains all nasty logic to call a web service. I just have inject it and to invoke it's call method with a TheWebServiceInfo (extracted from WebService and WebServiceOperation annotations) and request object.
TheWebServiceInfo(Suppose all fields have getters and setters)
public class TheWebServiceInfo {
private String service;
private String namespace;
private String operation;
}
WebServiceProxy
public class WebServiceProxy implements InvocationHandler {
#Autowired
private TheWebServiceCaller caller;
#Override
public Object invoke(Object target, Method method, Object[] args) throws Exception {
Object request = (null != args && args.length > 0) ? args[0] : null;
WebService webService = method.getDeclaringClass().getAnnotation(WebService.class);
WebServiceOperation webServiceOperation = method.getAnnotation(WebServiceOperation.class);
TheWebServiceInfo theInfo = createTheWebServiceInfo(webService, webServiceOperation);
return caller.call(theInfo, request);
}
private TheWebServiceInfo createTheWebServiceInfo(WebService webService, WebServiceOperation webServiceOperation) {
TheWebServiceInfo theInfo = new TheWebServiceInfo();
theInfo.setService(webService.service());
theInfo.setNamespace(webService.namespace());
theInfo.setOperation(webServiceOperation.operation());
return theInfo;
}
}
Implementaion of InvocationHandler is passed to Proxy.newProxyInstance (along with some other information) to create proxy objects. I need separat proxy objectes for each WebService annotated interface. I will now create a factory to proxy instances creation and name is as 'WebServiceProxyBeanFactory'. Instances created by this factory will become beans for corresponding WebService annotated interfaces.
A bit later, I will expose 'WebServiceProxy' and WebServiceProxyBeanFactory as beans. In 'WebServiceProxyBeanFactory', I will inject WebServiceProxy and used it. Please note that createWebServiceProxyBean uses generics. This is important.
WebServiceProxyBeanFactory
public class WebServiceProxyBeanFactory {
#Autowired
WebServiceProxy webServiceProxy;
#SuppressWarnings("unchecked")
public <WS> WS createWebServiceProxyBean(ClassLoader classLoader, Class<WS> clazz) {
return (WS) Proxy.newProxyInstance(classLoader, new Class[] {clazz}, webServiceProxy);
}
}
If you remember, earlier I have imported WebServiceProxyConfig in EnableWebServices annotations. WebServiceProxyConfig is used to expose WebServiceProxy and WebServiceProxyBeanFactory as beans.
WebServiceProxyConfig
#Configuration
public class WebServiceProxyConfig {
#Bean
public WebServiceProxy webServiceProxy() {
return new WebServiceProxy();
}
#Bean(name = "webServiceProxyBeanFactory")
public WebServiceProxyBeanFactory webServiceProxyBeanFactory() {
return new WebServiceProxyBeanFactory();
}
}
Now everything is in place. it's time to write a hook to start scanning Web service packages and register dynamic proxies as beans. I will provide implementation of ImportBeanDefinitionRegistrar.
WebServiceProxyBeansRegistrar
#Configuration
public class WebServiceProxyBeansRegistrar implements ImportBeanDefinitionRegistrar, BeanClassLoaderAware {
private ClassPathScanner classpathScanner;
private ClassLoader classLoader;
public WebServiceProxyBeansRegistrar() {
classpathScanner = new ClassPathScanner(false);
classpathScanner.addIncludeFilter(new AnnotationTypeFilter(WebService.class));
}
#Override
public void setBeanClassLoader(ClassLoader classLoader) {
this.classLoader = classLoader;
}
#Override
public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
String[] basePackages = getBasePackages(importingClassMetadata);
if (ArrayUtils.isNotEmpty(basePackages)) {
for (String basePackage : basePackages) {
createWebServicProxies(basePackage, registry);
}
}
}
private String[] getBasePackages(AnnotationMetadata importingClassMetadata) {
String[] basePackages = null;
MultiValueMap<String, Object> allAnnotationAttributes =
importingClassMetadata.getAllAnnotationAttributes(EnableWebServices.class.getName());
if (MapUtils.isNotEmpty(allAnnotationAttributes)) {
basePackages = (String[]) allAnnotationAttributes.getFirst("basePackages");
}
return basePackages;
}
private void createWebServicProxies(String basePackage, BeanDefinitionRegistry registry) {
try {
for (BeanDefinition beanDefinition : classpathScanner.findCandidateComponents(basePackage)) {
Class<?> clazz = Class.forName(beanDefinition.getBeanClassName());
WebService webService = clazz.getAnnotation(WebService.class);
String beanName = StringUtils.isNotEmpty(webService.bean())
? webService.bean() : ClassUtils.getShortNameAsProperty(clazz);
GenericBeanDefinition proxyBeanDefinition = new GenericBeanDefinition();
proxyBeanDefinition.setBeanClass(clazz);
ConstructorArgumentValues args = new ConstructorArgumentValues();
args.addGenericArgumentValue(classLoader);
args.addGenericArgumentValue(clazz);
proxyBeanDefinition.setConstructorArgumentValues(args);
proxyBeanDefinition.setFactoryBeanName("webServiceProxyBeanFactory");
proxyBeanDefinition.setFactoryMethodName("createWebServiceProxyBean");
registry.registerBeanDefinition(beanName, proxyBeanDefinition);
}
} catch (Exception e) {
System.out.println("Exception while createing proxy");
e.printStackTrace();
}
}
}
In this class, I extracted all packages provided in EnableWebServices annotation. for each extracted package, I used ClassPathScanner to scan. (Here logic can be refined to filter only WebService annotated interfaces). For each detected interface, I have registered a bean definitions. Please note I have used webServiceProxyBeanFactory and called its createWebServiceProxyBean with classLoader and type of interface. This factory method, when invoked by spring later, will return bean of same type as that of interface, so bean with correct type is registered. This bean can be injected anywhere with interface type. Moreover, WebServiceProxy can inject and use any other bean. So autowiring will also work as expected.
Is your InvocationHandler a bean? You should create it as a bean, not just a simple object to get Autowired working
I was thinking about the same problem but in a slightly more lightweight context. I don't need to load dynamicaly all the webservice clients. So instead I used a FactoryBean and within this factory bean I constructed the dynamic proxy. Here is one example where Autowiring of the service works:
public class CurrencyServiceWithDynamicProxy extends AbstractFactoryBean<CurrencyService> {
ServiceClientConfiguration clientConfiguration;
Object proxy;
#Autowired
public CurrencySyncFactoryDynamicProxy(ServiceClientConfigurationProvider serviceClientConfigurationProvider) {
this.clientConfiguration = serviceClientConfigurationProvider.createClientConfig("currency");
proxy = Proxy.newProxyInstance(getClass().getClassLoader(), new Class<?>[] { getObjectType() }, new MyInvocationHandler());
}
#Override
public Class<CurrencySync> getObjectType() {
// TODO Auto-generated method stub
return CurrencyService.class;
}
#Override
public CurrencySync createInstance() throws Exception {
// do some creational logic
return (CurrencySync)proxy;
}
public CurrencySync createService() {
JaxWsProxyFactoryBean factory = new JaxWsProxyFactoryBean();
factory.setServiceClass(getObjectType());
factory.getFeatures().add(som features);
return getObjectType().cast(factory.create());
}
}
With respect of the accepted answer this factory example can easily be extended into a more dynamic version.

Spring MVC accessing Spring Security ConfigAttributes?

I want to produce HTTP Response Body with an error message referencing something like _"missing ... 'CUSTOM_AUTHORITY'"_ in addition to a 403 Forbidden HTTP Status code.
My application is Spring Boot with a Spring-Security-Secured #PreAuthorize method within a Spring-MVC-REST #Controller:
MyController
#Controller
#RequestMapping("/foo")
public FooController{
#PreAuthorize("hasAuthority('CUSTOM_AUTHORITY')")
public Object getSomething(){ ... }
}
GlobalExceptionHandlerResolver
#ControllerAdvice
public class GlobalExceptionHandler {
#ExceptionHandler(AccessDeniedException.class)
#ResponseStatus(HttpStatus.FORBIDDEN)
public Object forbidden(AccessDeniedException exception){ ... }
}
What I want is to expose/inject Collection<ConfigAttribute>. The Spring Security docs reference it.
There doesn't seem to be a straightforward way of accomplishing this. The AccessDecisionManager (which is AffirmativeBased) throws the AccessDeniedException with none of the information you want. So if you want to "expose/inject" the Collection<ConfigAttribute>, you'll want to provide your own AccessDecisionManager that throws a custom exception that holds the ConfigAttributes.
The easiest way to do this could be to wrap the default AccessDecisionManager with your own and delegate method calls to it:
#Configuration
#EnableGlobalMethodSecurity(prePostEnabled=true)
CustomMethodSecurityConfig extends GlobalMethodSecurityConfiguration
#Override
protected AccessDecisionManager accessDecisionManager() {
AccessDecisionManager default = super.accessDecisionManager();
MyCustomDecisionManager custom = new CustomDecisionManager(default);
}
}
You could define your custom AccessDecisionManager as follows:
public class MyCustomDecisionManager implements AccessDecisionManager {
private AccessDecisionManager default;
public MyCustomDecisionManager(AccessDecisionManager acm) {
this.default = acm;
}
#Override
public void decide(Authentication authentication, Object object, Collection<ConfigAttribute> configAttributes) throws AccessDeniedException, InsufficientAuthenticationException{
try {
default.decide(authentication, object, configAttributes)
} catch(AccessDeniedException ex) {
throw new CustomAccessDeniedException(ex.getMessage(), configAttributes);
}
}
// other methods delegate to default
}
Now whenever access is denied, you will get an exception that holds the Collection<ConfigAttribute>.
Your custom exception could look like this:
public class CustomAccessDeniedException extends AccessDeniedException {
private Collection<ConfigAttribute> attributes;
public CustomAccessDeniedException(String message, Collection<ConfigAttribute> attr) {
super(message);
this.attributes = attr;
}
public Collection<ConfigAttribute> getAttributes() {
return this.attributes;
}
}
Now your #ExceptionHandler could handle your CustomAccessDeniedException and have access to the ConfigAttributes.
HOWEVER...
I am not sure that will provide you with the error message you wanted. The ConfigAttribute interface only has one method:
String getAttribute();
And the javadoc states:
If the ConfigAttribute cannot be expressed with sufficient precision as a String, null should be returned.
Since we can't rely on the interface method, how you deal with each ConfigAttribute will be heavily dependent on the type of the particular object you're dealing with.
For example, the ConfigAttribute that corresponds to #PreAuthorize("hasAuthority('CUSTOM_AUTHORITY')") is PreInvocationExpressionAttribute, and to print something that resembles what you want, you could do:
PreInvocationExpressionAttribute attr = (PreInvocationExpressionAttribute)configAttribute;
String expressionString = attr.getAuthorizeExpression().getExpressionString();
System.out.println(expressionString); // "hasAuthority('CUSTOM_AUTHORITY')"
That's the major drawback. Also, you would get ALL the ConfigAttributes, not necessarily the ones that failed.

Spring Data Rest: custom Converter<Entity, Resource> is never invoked

I'm trying to implement a custom Converter for an Entity to a Resource object with Spring Data Rest, but the Converter is never invoked.
I'm following this documentation:
If your project needs to have output in a different format, however,
it’s possible to completely replace the default outgoing JSON
representation with your own. If you register your own
ConversionService in the ApplicationContext and register your own
Converter, then you can return a Resource
implementation of your choosing.
That's what I've tried to do.
I have a #Configuration class that extends RepositoryRestMvcConfiguration, with this method:
#Configuration
#EnableWebMvc
#EnableHypermediaSupport(type = HypermediaType.HAL)
public class RepositoryBaseConfiguration extends RepositoryRestMvcConfiguration {
#Override
public DefaultFormattingConversionService defaultConversionService() {
return super.defaultConversionService();
}
}
And I have a Class that extends RepositoryRestConfigurerAdapter, with this implementation:
#Configuration
public class RepositoryBaseConfigurerAdapter extends RepositoryRestConfigurerAdapter {
#Override
public void configureConversionService(ConfigurableConversionService conversionService) {
if(!conversionService.canConvert(Entity.class, Resource.class))
conversionService.addConverter(new EntityConverter());
super.configureConversionService(conversionService);
}
}
Both methods of those two classes are correctly invoked and managed, so it's natural to think that the Converter has been registered in the Application Context...
This is my custom converter EntityConverter:
#Component
public class EntityConverter implements Converter<Entity, Resource> {
#Override
public Resource convert(Entity source) {
System.out.println("method convert of class EntityConverter");
return null;
}
}
The method "convert" is never invoked by Spring Data Rest.
What's wrong/missing ?
Thanks in advance.

Check the state validity of a Spring proxied bean without try-catch

I have a bean being created by a service with the following class:
#Configuration
public class AccessManager {
#Bean(name="access", destroyMethod="destroy")
#Scope(value="session", proxyMode=ScopedProxyMode.TARGET_CLASS)
#Autowired
public Access create(HttpServletRequest request) {
System.out.println(request.getRemoteAddr());
return new Access();
}
}
Everything works as expected, except that when the application is starting, this method is being called, probably because I have some other singleton beans that use the Access bean. At the start up there is no request bound to the Thread, and it's expected to get a java.lang.IllegalStateException when trying to access any property of the request parameter.
No problem. The question is, is it possible to check if the underlying HttpServletRequest of the proxy request is null before calling a property that raises the exception?
You probably want to take a look at RequestContextHolder#getRequestAttributes(). That will return null if you're not currently in a context where request scope could be used.
#Configuration
public class AccessManager {
#Bean(name="access", destroyMethod="destroy")
#Scope(value="session", proxyMode=ScopedProxyMode.TARGET_CLASS)
#Autowired
public Access create(HttpServletRequest request) {
if (RequestContextHolder.getRequestAttributes() != null) {
System.out.println(request.getRemoteAddr());
}
return new Access();
}
}
I think the issue here is with separation of concerns. Usually your service layer should not have any dependency on the servlet classes. This is very much a controller/UI concern.
Your service class should be provided with the properties which it needs to do its job. In this case a String. This service method should be called from a controller method which is injected with the servlet request.
Something like the following:
#Controller
public class MyController {
#Autowired
private AccessManager accessManager;
#RequestMapping
public void handleRequest(HttpServletRequest request) {
accessManager.create(request.getRemoteAddr());
}
}
and your service would then look like this:
#Service
public class AccessManager {
public Access create(String remoteAddress) {
return new Access();
}
}
To sum up, anything annotated as #Service shouldn't have access to the Request.

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