XStreamMarshaller ignore unknown elements - spring

After change data model on server side my XStream client throw Exception
com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$UnknownFieldException: No such field {fieldName}
To prevent this behavior I try to do something to ignore unknown elements.
I am using XStreamMarshaller from Spring-oxm 4.0.5 and XStream 1.4.5. I known that since XStream version 1.4.5 is available method ignoreUnknownElements().
XStreamMarshaller marshaller = new XStreamMarshaller();
marshaller.setStreamDriver(streamDriver);
marshaller.setAutodetectAnnotations(autodetectAnnotations);
marshaller.getXStream().ignoreUnknownElements();
Above solution doesn't work and I still get mentioned exception.
I have client side model copied from server.
For example:
public class Device implements Serializable {
protected String device_id;
protected String device_model_code;
protected String device_model_name;
protected String device_name;
//getters, setters
}
If I comment field for example device_model I will have Exception
com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter$UnknownFieldException: No such field device_name
How can I solve my problem? How can I implement XStreamMarshaller to ignore unknown elements?

First thing is that method ignoreUnknownElements() available since XStream 1.4.5 is only for marshaling not for unmarshaling. So it doesn't work if somebody adds a new field in data model on server side.
To solve described problem you have to override protected method constructXStream() from org.springframework.oxm.xstream.XStreamMarshaller implementation:
public class CustomXStreamMarshaller extends XStreamMarshaller {
#Override
protected XStream constructXStream() {
// The referenced XStream constructor has been deprecated as of 1.4.5.
// We're preserving this call for broader XStream 1.4.x compatibility.
return new XStream() {
#Override
protected MapperWrapper wrapMapper(MapperWrapper next) {
return new MapperWrapper(next) {
#Override
public boolean shouldSerializeMember(Class definedIn, String fieldName) {
if (definedIn == Object.class) {
return false;
}
return super.shouldSerializeMember(definedIn, fieldName);
}
};
}
};
}}
You only need to use your own implementation in XStreamMarshaller declaration:
CustomXStreamMarshaller marshaller = new CustomXStreamMarshaller();
marshaller.setStreamDriver(streamDriver);
marshaller.setAutodetectAnnotations(autodetectAnnotations);

Related

How to handle Access Denied properly in Vaadin 14 LTS

I started implementing authentication and authorization for our applications written in Spring Boot (2.2.6.RELEASE) and Vaadin 14 LTS (14.6.1).
I have followed those resources:
Securing your app with Spring Security
Router Exception Handling
I have code for checking whether logged-in user has access rights to specified resources implemented in beforeEnter method. The problem is with invocation of event.rerouteToError(AccessDeniedException.class);. It tries to create an instance of the specified exception with reflection but fails because it does not contain public no-arg constructor.
private void beforeEnter(final BeforeEnterEvent event) {
if (!AuthView.class.equals(event.getNavigationTarget()) && !AuthUtils.isUserLoggedIn()) {
event.rerouteTo(AuthView.class);
}
if (!AuthUtils.isAccessGranted(event.getNavigationTarget())) {
event.rerouteToError(AccessDeniedException.class);
}
}
java.lang.IllegalArgumentException: Unable to create an instance of 'org.springframework.security.access.AccessDeniedException'. Make sure the class has a public no-arg constructor.
at com.vaadin.flow.internal.ReflectTools.createProxyInstance(ReflectTools.java:519)
at com.vaadin.flow.internal.ReflectTools.createInstance(ReflectTools.java:451)
at com.vaadin.flow.router.BeforeEvent.rerouteToError(BeforeEvent.java:720)
at com.vaadin.flow.router.BeforeEvent.rerouteToError(BeforeEvent.java:704)
What can be the best solution for that case? I am thinking about two possible solutions:
First instantiate AccessDeniedException and then pass it to overloaded method in BeforeEvent: public void rerouteToError(Exception exception, String customMessage) which should skip creating exception object by reflection
Create dedicated ErrorView and use method public void rerouteTo(Class<? extends Component> routeTargetType, RouteParameters parameters) of BeforeEvent
I decided to follow Leif Åstrand's answer. I created custom AccessDeniedException and appropriate error handler. Here is my implementation. Maybe it will be helpful for someone.
public class AccessDeniedException extends RuntimeException {
private final int code;
public AccessDeniedException() {
super("common.error.403.details");
this.code = HttpServletResponse.SC_FORBIDDEN;
}
public int getCode() {
return code;
}
}
#Tag(Tag.DIV)
#CssImport(value = "./styles/access-denied-view.css")
#CssImport(value = "./styles/access-denied-box.css", themeFor = "vaadin-details")
public class AccessDeniedExceptionHandler extends VerticalLayout implements HasErrorParameter<AccessDeniedException> {
private final Details details;
public AccessDeniedExceptionHandler() {
setWidthFull();
setHeight("100vh");
setPadding(false);
setDefaultHorizontalComponentAlignment(Alignment.CENTER);
setJustifyContentMode(JustifyContentMode.CENTER);
setClassName(ComponentConstants.ACCESS_DENIED_VIEW);
this.details = new Details();
this.details.setClassName(ComponentConstants.ACCESS_DENIED_BOX);
this.details.addThemeVariants(DetailsVariant.REVERSE, DetailsVariant.FILLED);
this.details.setOpened(true);
add(this.details);
}
#Override
public final int setErrorParameter(final BeforeEnterEvent event, final ErrorParameter<AccessDeniedException> parameter) {
final int code = parameter.getException().getCode();
this.details.setSummaryText(getTranslation("common.error.403.header", code));
this.details.setContent(new Text(getTranslation(parameter.getException().getMessage())));
return code;
}
}
I would recommend creating a custom exception type instead of reusing AccessDeniedException from Spring. In that way, you don't have to deal with the required error message at all.
As you mentioned in your first solution, you could do:
event.rerouteToError(new AccessDeniedException("Navigation target not permitted"), "");
or maybe also specify the customMessage if you want. If you see the implementation of the rerouteToError(Class) method, it just passes empty customMessage and creates the Exception - which you could do manually and that's completely acceptable. I recommend this solution.
Another solution could be to subclass AccessDeniedException and use that with reflection:
public class RouteAccessDeniedException extends AccessDeniedException {
public RouteAccessDeniedException() {
super("Navigation target not permitted");
}
}
I don't recommend this solution.

JAXBElement: providing codec (/converter?) for class java.lang.Class

I have been evaluating to adopt spring-data-mongodb for a project. In summary, my aim is:
Using existing XML schema files to generate Java classes.
This is achieved using JAXB xjc
The root class is TSDProductDataType and is further modeled as below:
The thing to note here is that ExtensionType contains protected List<Object> any; allowing it to store Objects of any class. In my case, it is amongst the classes named TSDModule_Name_HereModuleType and can be browsed here
Use spring-data-mongodb as persistence store
This is achieved using a simple ProductDataRepository
#RepositoryRestResource(collectionResourceRel = "product", path = "product")
public interface ProductDataRepository extends MongoRepository<TSDProductDataType, String> {
TSDProductDataType queryByGtin(#Param("gtin") String gtin);
}
The unmarshalled TSDProductDataType, however, contains JAXBElement which spring-data-mongodb doesn't seem to handle by itself and throws a CodecConfigurationException org.bson.codecs.configuration.CodecConfigurationException: Can't find a codec for class java.lang.Class.
Here is the faulty statement:
TSDProductDataType tsdProductDataType = jaxbElement.getValue();
repository.save(tsdProductDataType);
I tried playing around with Converters for spring-data-mongodb as explained here, however, it seems I am missing something since the exception is about "Codecs" and not "Converters".
Any help is appreciated.
EDIT:
Adding converters for JAXBElement
Note: Works with version 1.5.6.RELEASE of org.springframework.boot::spring-boot-starter-parent. With version 2.0.0.M3, hell breaks loose
It seems that I missed something while trying to add converter earlier. So, I added it like below for testing:
#Component
#ReadingConverter
public class JAXBElementReadConverter implements Converter<DBObject, JAXBElement> {
//#Autowired
//MongoConverter converter;
#Override
public JAXBElement convert(DBObject dbObject) {
Class declaredType, scope;
QName name = qNameFromString((String)dbObject.get("name"));
Object rawValue = dbObject.get("value");
try {
declaredType = Class.forName((String)dbObject.get("declaredType"));
} catch (ClassNotFoundException e) {
if (rawValue.getClass().isArray()) declaredType = List.class;
else declaredType = LinkedHashMap.class;
}
try {
scope = Class.forName((String) dbObject.get("scope"));
} catch (ClassNotFoundException e) {
scope = JAXBElement.GlobalScope.class;
}
//Object value = rawValue instanceof DBObject ? converter.read(declaredType, (DBObject) rawValue) : rawValue;
Object value = "TODO";
return new JAXBElement(name, declaredType, scope, value);
}
QName qNameFromString(String s) {
String[] parts = s.split("[{}]");
if (parts.length > 2) return new QName(parts[1], parts[2], parts[0]);
if (parts.length == 1) return new QName(parts[0]);
return new QName("undef");
}
}
#Component
#WritingConverter
public class JAXBElementWriteConverter implements Converter<JAXBElement, DBObject> {
//#Autowired
//MongoConverter converter;
#Override
public DBObject convert(JAXBElement jaxbElement) {
DBObject dbObject = new BasicDBObject();
dbObject.put("name", qNameToString(jaxbElement.getName()));
dbObject.put("declaredType", jaxbElement.getDeclaredType().getName());
dbObject.put("scope", jaxbElement.getScope().getCanonicalName());
//dbObject.put("value", converter.convertToMongoType(jaxbElement.getValue()));
dbObject.put("value", "TODO");
dbObject.put("_class", JAXBElement.class.getName());
return dbObject;
}
public String qNameToString(QName name) {
if (name.getNamespaceURI() == XMLConstants.NULL_NS_URI) return name.getLocalPart();
return name.getPrefix() + '{' + name.getNamespaceURI() + '}' + name.getLocalPart();
}
}
#SpringBootApplication
public class TsdApplication {
public static void main(String[] args) {
SpringApplication.run(TsdApplication.class, args);
}
#Bean
public CustomConversions customConversions() {
return new CustomConversions(Arrays.asList(
new JAXBElementReadConverter(),
new JAXBElementWriteConverter()
));
}
}
So far so good. However, how do I instantiate MongoConverter converter;?
MongoConverter is an interface so I guess I need an instantiable class adhering to this interface. Any suggestions?
I understand the desire for convenience in being able to just map an existing domain object to the database layer with no boilerplate, but even if you weren't having the JAXB class structure issue, I would still be recommending away from using it verbatim. Unless this is a simple one-off project, you almost definitely will hit a point where your domain models will need to change but your persisted data need to remain in an existing state. If you are just straight persisting the data, you have no mechanism to convert between a newer domain schema and an older persisted data scheme. Versioning of the persisted data scheme would be wise too.
The link you posted for writing the customer converters is one way to achieve this and fits in nicely with the Spring ecosystem. That method should also solve the issue you are experiencing (about the underlying messy JAXB data structure not converting cleanly).
Are you unable to get that method working? Ensure you are loading them into the Spring context with #Component plus auto-class scanning or manually via some Configuration class.
EDIT to address your EDIT:
Add the following to each of your converters:
private final MongoConverter converter;
public JAXBElement____Converter(MongoConverter converter) {
this.converter = converter;
}
Try changing your bean definition to:
#Bean
public CustomConversions customConversions(#Lazy MongoConverter converter) {
return new CustomConversions(Arrays.asList(
new JAXBElementReadConverter(converter),
new JAXBElementWriteConverter(converter)
));
}

Read Application Object from GemFire using Spring Data GemFire. Data stored using SpringXD's gemfire-json-server

I'm using the gemfire-json-server module in SpringXD to populate a GemFire grid with json representation of “Order” objects. I understand the gemfire-json-server module saves data in Pdx form in GemFire. I’d like to read the contents of the GemFire grid into an “Order” object in my application. I get a ClassCastException that reads:
java.lang.ClassCastException: com.gemstone.gemfire.pdx.internal.PdxInstanceImpl cannot be cast to org.apache.geode.demo.cc.model.Order
I’m using the Spring Data GemFire libraries to read contents of the cluster. The code snippet to read the contents of the Grid follows:
public interface OrderRepository extends GemfireRepository<Order, String>{
Order findByTransactionId(String transactionId);
}
How can I use Spring Data GemFire to convert data read from the GemFire cluster into an Order object?
Note: The data was initially stored in GemFire using SpringXD's gemfire-json-server-module
Still waiting to hear back from the GemFire PDX engineering team, specifically on Region.get(key), but, interestingly enough if you annotate your application domain object with...
#JsonTypeInfo(use = JsonTypeInfo.Id.CLASS, include = JsonTypeInfo.As.PROPERTY, property = "#type")
public class Order ... {
...
}
This works!
Under-the-hood I knew the GemFire JSONFormatter class (see here) used Jackson's API to un/marshal (de/serialize) JSON data to and from PDX.
However, the orderRepository.findOne(ID) and ordersRegion.get(key) still do not function as I would expect. See updated test class below for more details.
Will report back again when I have more information.
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = GemFireConfiguration.class)
#SuppressWarnings("unused")
public class JsonToPdxToObjectDataAccessIntegrationTest {
protected static final AtomicLong ID_SEQUENCE = new AtomicLong(0l);
private Order amazon;
private Order bestBuy;
private Order target;
private Order walmart;
#Autowired
private OrderRepository orderRepository;
#Resource(name = "Orders")
private com.gemstone.gemfire.cache.Region<Long, Object> orders;
protected Order createOrder(String name) {
return createOrder(ID_SEQUENCE.incrementAndGet(), name);
}
protected Order createOrder(Long id, String name) {
return new Order(id, name);
}
protected <T> T fromPdx(Object pdxInstance, Class<T> toType) {
try {
if (pdxInstance == null) {
return null;
}
else if (toType.isInstance(pdxInstance)) {
return toType.cast(pdxInstance);
}
else if (pdxInstance instanceof PdxInstance) {
return new ObjectMapper().readValue(JSONFormatter.toJSON(((PdxInstance) pdxInstance)), toType);
}
else {
throw new IllegalArgumentException(String.format("Expected object of type PdxInstance; but was (%1$s)",
pdxInstance.getClass().getName()));
}
}
catch (IOException e) {
throw new RuntimeException(String.format("Failed to convert PDX to object of type (%1$s)", toType), e);
}
}
protected void log(Object value) {
System.out.printf("Object of Type (%1$s) has Value (%2$s)", ObjectUtils.nullSafeClassName(value), value);
}
protected Order put(Order order) {
Object existingOrder = orders.putIfAbsent(order.getTransactionId(), toPdx(order));
return (existingOrder != null ? fromPdx(existingOrder, Order.class) : order);
}
protected PdxInstance toPdx(Object obj) {
try {
return JSONFormatter.fromJSON(new ObjectMapper().writeValueAsString(obj));
}
catch (JsonProcessingException e) {
throw new RuntimeException(String.format("Failed to convert object (%1$s) to JSON", obj), e);
}
}
#Before
public void setup() {
amazon = put(createOrder("Amazon Order"));
bestBuy = put(createOrder("BestBuy Order"));
target = put(createOrder("Target Order"));
walmart = put(createOrder("Wal-Mart Order"));
}
#Test
public void regionGet() {
assertThat((Order) orders.get(amazon.getTransactionId()), is(equalTo(amazon)));
}
#Test
public void repositoryFindOneMethod() {
log(orderRepository.findOne(target.getTransactionId()));
assertThat(orderRepository.findOne(target.getTransactionId()), is(equalTo(target)));
}
#Test
public void repositoryQueryMethod() {
assertThat(orderRepository.findByTransactionId(amazon.getTransactionId()), is(equalTo(amazon)));
assertThat(orderRepository.findByTransactionId(bestBuy.getTransactionId()), is(equalTo(bestBuy)));
assertThat(orderRepository.findByTransactionId(target.getTransactionId()), is(equalTo(target)));
assertThat(orderRepository.findByTransactionId(walmart.getTransactionId()), is(equalTo(walmart)));
}
#Region("Orders")
#JsonTypeInfo(use = JsonTypeInfo.Id.CLASS, include = JsonTypeInfo.As.PROPERTY, property = "#type")
public static class Order implements PdxSerializable {
protected static final OrderPdxSerializer pdxSerializer = new OrderPdxSerializer();
#Id
private Long transactionId;
private String name;
public Order() {
}
public Order(Long transactionId) {
this.transactionId = transactionId;
}
public Order(Long transactionId, String name) {
this.transactionId = transactionId;
this.name = name;
}
public String getName() {
return name;
}
public void setName(final String name) {
this.name = name;
}
public Long getTransactionId() {
return transactionId;
}
public void setTransactionId(final Long transactionId) {
this.transactionId = transactionId;
}
#Override
public void fromData(PdxReader reader) {
Order order = (Order) pdxSerializer.fromData(Order.class, reader);
if (order != null) {
this.transactionId = order.getTransactionId();
this.name = order.getName();
}
}
#Override
public void toData(PdxWriter writer) {
pdxSerializer.toData(this, writer);
}
#Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof Order)) {
return false;
}
Order that = (Order) obj;
return ObjectUtils.nullSafeEquals(this.getTransactionId(), that.getTransactionId());
}
#Override
public int hashCode() {
int hashValue = 17;
hashValue = 37 * hashValue + ObjectUtils.nullSafeHashCode(getTransactionId());
return hashValue;
}
#Override
public String toString() {
return String.format("{ #type = %1$s, id = %2$d, name = %3$s }",
getClass().getName(), getTransactionId(), getName());
}
}
public static class OrderPdxSerializer implements PdxSerializer {
#Override
public Object fromData(Class<?> type, PdxReader in) {
if (Order.class.equals(type)) {
return new Order(in.readLong("transactionId"), in.readString("name"));
}
return null;
}
#Override
public boolean toData(Object obj, PdxWriter out) {
if (obj instanceof Order) {
Order order = (Order) obj;
out.writeLong("transactionId", order.getTransactionId());
out.writeString("name", order.getName());
return true;
}
return false;
}
}
public interface OrderRepository extends GemfireRepository<Order, Long> {
Order findByTransactionId(Long transactionId);
}
#Configuration
protected static class GemFireConfiguration {
#Bean
public Properties gemfireProperties() {
Properties gemfireProperties = new Properties();
gemfireProperties.setProperty("name", JsonToPdxToObjectDataAccessIntegrationTest.class.getSimpleName());
gemfireProperties.setProperty("mcast-port", "0");
gemfireProperties.setProperty("log-level", "warning");
return gemfireProperties;
}
#Bean
public CacheFactoryBean gemfireCache(Properties gemfireProperties) {
CacheFactoryBean cacheFactoryBean = new CacheFactoryBean();
cacheFactoryBean.setProperties(gemfireProperties);
//cacheFactoryBean.setPdxSerializer(new MappingPdxSerializer());
cacheFactoryBean.setPdxSerializer(new OrderPdxSerializer());
cacheFactoryBean.setPdxReadSerialized(false);
return cacheFactoryBean;
}
#Bean(name = "Orders")
public PartitionedRegionFactoryBean ordersRegion(Cache gemfireCache) {
PartitionedRegionFactoryBean regionFactoryBean = new PartitionedRegionFactoryBean();
regionFactoryBean.setCache(gemfireCache);
regionFactoryBean.setName("Orders");
regionFactoryBean.setPersistent(false);
return regionFactoryBean;
}
#Bean
public GemfireRepositoryFactoryBean orderRepository() {
GemfireRepositoryFactoryBean<OrderRepository, Order, Long> repositoryFactoryBean =
new GemfireRepositoryFactoryBean<>();
repositoryFactoryBean.setRepositoryInterface(OrderRepository.class);
return repositoryFactoryBean;
}
}
}
So, as you are aware, GemFire (and by extension, Apache Geode) stores JSON in PDX format (as a PdxInstance). This is so GemFire can interoperate with many different language-based clients (native C++/C#, web-oriented (JavaScript, Pyhton, Ruby, etc) using the Developer REST API, in addition to Java) and also to be able to use OQL to query the JSON data.
After a bit of experimentation, I am surprised GemFire is not behaving as I would expect. I created an example, self-contained test class (i.e. no Spring XD, of course) that simulates your use case... essentially storing JSON data in GemFire as PDX and then attempting to read the data back out as the Order application domain object type using the Repository abstraction, logical enough.
Given the use of the Repository abstraction and implementation from Spring Data GemFire, the infrastructure will attempt to access the application domain object based on the Repository generic type parameter (in this case "Order" from the "OrderRepository" definition).
However, the data is stored in PDX, so now what?
No matter, Spring Data GemFire provides the MappingPdxSerializer class to convert PDX instances back to application domain objects using the same "mapping meta-data" that the Repository infrastructure uses. Cool, so I plug that in...
#Bean
public CacheFactoryBean gemfireCache(Properties gemfireProperties) {
CacheFactoryBean cacheFactoryBean = new CacheFactoryBean();
cacheFactoryBean.setProperties(gemfireProperties);
cacheFactoryBean.setPdxSerializer(new MappingPdxSerializer());
cacheFactoryBean.setPdxReadSerialized(false);
return cacheFactoryBean;
}
You will also notice, I set the PDX 'read-serialized' property (cacheFactoryBean.setPdxReadSerialized(false);) to false in order to ensure data access operations return the domain object and not the PDX instance.
However, this had no affect on the query method. In fact, it had no affect on the following operations either...
orderRepository.findOne(amazonOrder.getTransactionId());
ordersRegion.get(amazonOrder.getTransactionId());
Both calls returned a PdxInstance. Note, the implementation of OrderRepository.findOne(..) is based on SimpleGemfireRepository.findOne(key), which uses GemfireTemplate.get(key), which just performs Region.get(key), and so is effectively the same as (ordersRegion.get(amazonOrder.getTransactionId();). The outcome should not be, especially with Region.get() and read-serialized set to false.
With the OQL query (SELECT * FROM /Orders WHERE transactionId = $1) generated from the findByTransactionId(String id), the Repository infrastructure has a bit less control over what the GemFire query engine will return based on what the caller (OrderRepository) expects (based on the generic type parameter), so running OQL statements could potentially behave differently than direct Region access using get.
Next, I went onto try modifying the Order type to implement PdxSerializable, to handle the conversion during data access operations (direct Region access with get, OQL, or otherwise). This had no affect.
So, I tried to implement a custom PdxSerializer for Order objects. This had no affect either.
The only thing I can conclude at this point is something is getting lost in translation between Order -> JSON -> PDX and then from PDX -> Order. Seemingly, GemFire needs additional type meta-data required by PDX (something like #JsonTypeInfo(use = JsonTypeInfo.Id.CLASS, include = JsonTypeInfo.As.PROPERTY, property = "#type") in the JSON data that PDXFormatter recognizes, though I am not certain it does.
Note, in my test class, I used Jackson's ObjectMapper to serialize the Order to JSON and then GemFire's JSONFormatter to serialize the JSON to PDX, which I suspect Spring XD is doing similarly under-the-hood. In fact, Spring XD uses Spring Data GemFire and is most likely using the JSON Region Auto Proxy support. That is exactly what SDG's JSONRegionAdvice object does (see here).
Anyway, I have an inquiry out to the rest of the GemFire engineering team. There are also things that could be done in Spring Data GemFire to ensure the PDX data is converted, such as making use of the MappingPdxSerializer directly to convert the data automatically on behalf of the caller if the data is indeed of type PdxInstance. Similar to how JSON Region Auto Proxying works, you could write AOP interceptor for the Orders Region to automagicaly convert PDX to an Order.
Though, I don't think any of this should be necessary as GemFire should be doing the right thing in this case. Sorry I don't have a better answer right now. Let's see what I find out.
Cheers and stay tuned!
See subsequent post for test code.

#MessageMapping with placeholders

I am working with Spring-websocket and I have the following problem:
I am trying to put a placeholder inside a #MessageMapping annotation in order to get the url from properties. It works with #RequestMapping but not with #MessageMapping.
If I use this placeholder, the URL is null. Any idea or suggestion?
Example:
#RequestMapping(value= "${myProperty}")
#MessageMapping("${myProperty}")
Rossen Stoyanchev added placeholder support for #MessageMapping and #SubscribeMapping methods.
See Jira issue: https://jira.spring.io/browse/SPR-13271
Spring allows you to use property placeholders in #RequestMapping, but not in #MessageMapping. This is 'cause the MessageHandler. So, we need to override the default MessageHandler to do this.
WebSocketAnnotationMethodMessageHandler does not support placeholders and you need add this support yourself.
For simplicity I just created another WebSocketAnnotationMethodMessageHandler class in my project at the same package of the original, org.springframework.web.socket.messaging, and override getMappingForMethod method from SimpAnnotationMethodMessageHandler with same content, changing only how SimpMessageMappingInfo is contructed using this with this methods (private in WebSocketAnnotationMethodMessageHandler):
private SimpMessageMappingInfo createMessageMappingCondition(final MessageMapping annotation) {
return new SimpMessageMappingInfo(SimpMessageTypeMessageCondition.MESSAGE, new DestinationPatternsMessageCondition(
this.resolveAnnotationValues(annotation.value()), this.getPathMatcher()));
}
private SimpMessageMappingInfo createSubscribeCondition(final SubscribeMapping annotation) {
final SimpMessageTypeMessageCondition messageTypeMessageCondition = SimpMessageTypeMessageCondition.SUBSCRIBE;
return new SimpMessageMappingInfo(messageTypeMessageCondition, new DestinationPatternsMessageCondition(
this.resolveAnnotationValues(annotation.value()), this.getPathMatcher()));
}
These methods now will resolve value considering properties (calling resolveAnnotationValues method), so we need use something like this:
private String[] resolveAnnotationValues(final String[] destinationNames) {
final int length = destinationNames.length;
final String[] result = new String[length];
for (int i = 0; i < length; i++) {
result[i] = this.resolveAnnotationValue(destinationNames[i]);
}
return result;
}
private String resolveAnnotationValue(final String name) {
if (!(this.getApplicationContext() instanceof ConfigurableApplicationContext)) {
return name;
}
final ConfigurableApplicationContext applicationContext = (ConfigurableApplicationContext) this.getApplicationContext();
final ConfigurableBeanFactory configurableBeanFactory = applicationContext.getBeanFactory();
final String placeholdersResolved = configurableBeanFactory.resolveEmbeddedValue(name);
final BeanExpressionResolver exprResolver = configurableBeanFactory.getBeanExpressionResolver();
if (exprResolver == null) {
return name;
}
final Object result = exprResolver.evaluate(placeholdersResolved, new BeanExpressionContext(configurableBeanFactory, null));
return result != null ? result.toString() : name;
}
You still need to define a PropertySourcesPlaceholderConfigurer bean in your configuration.
If you are using XML based configuration, include something like this:
<context:property-placeholder location="classpath:/META-INF/spring/url-mapping-config.properties" />
If you are using Java based configuration, you can try in this way:
#Configuration
#PropertySources(value = #PropertySource("classpath:/META-INF/spring/url-mapping-config.properties"))
public class URLMappingConfig {
#Bean
public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer() {
return new PropertySourcesPlaceholderConfigurer();
}
}
Obs.: in this case, url-mapping-config.properties file are in a gradle/maven project in src\main\resources\META-INF\spring folder and content look like this:
myPropertyWS=urlvaluews
This is my sample controller:
#Controller
public class WebSocketController {
#SendTo("/topic/test")
#MessageMapping("${myPropertyWS}")
public String test() throws Exception {
Thread.sleep(4000); // simulated delay
return "OK";
}
}
With default MessageHandler startup log will print something like this:
INFO: Mapped "{[/${myPropertyWS}],messageType=[MESSAGE]}" onto public java.lang.String com.brunocesar.controller.WebSocketController.test() throws java.lang.Exception
And with our MessageHandler now print this:
INFO: Mapped "{[/urlvaluews],messageType=[MESSAGE]}" onto public java.lang.String com.brunocesar.controller.WebSocketController.test() throws java.lang.Exception
See in this gist the full WebSocketAnnotationMethodMessageHandler implementation.
EDIT: this solution resolves the problem for versions before 4.2 GA. For more information, see this jira.
Update :
Now I understood what you mean, but I think that is not possible(yet).
Documentation does not mention anything related to Path mapping URIs.
Old answer
Use
#MessageMapping("/handler/{myProperty}")
instead of
#MessageMapping("/handler/${myProperty}")
And use it like this:
#MessageMapping("/myHandler/{username}")
public void handleTextMessage(#DestinationVariable String username,Message message) {
//do something
}
#MessageMapping("/chat/{roomId}")
public Message handleMessages(#DestinationVariable("roomId") String roomId, #Payload Message message, Traveler traveler) throws Exception {
System.out.println("Message received for room: " + roomId);
System.out.println("User: " + traveler.toString());
// store message in database
message.setAuthor(traveler);
message.setChatRoomId(Integer.parseInt(roomId));
int id = MessageRepository.getInstance().save(message);
message.setId(id);
return message;
}

Get resteasy servlet context without annotation params

Quick project explanation: We have a built application based on JSF2 + Spring with Dynamic data sources. The data reference control is made with a spring-config:
<bean id="dataSource" class="com.xxxx.xxxx.CustomerRoutingDataSource">
....
and a class (referenced above):
public class CustomerRoutingDataSource extends AbstractRoutingDataSource {
#Override
protected Object determineCurrentLookupKey() {
return CustomerContextHolder.getCustomerType();
}
public Logger getParentLogger() throws SQLFeatureNotSupportedException {
return null;
}
}
the CustomerContextHolder called above is as follows:
public class CustomerContextHolder {
private static final ThreadLocal<String> contextHolder = new ThreadLocal<String>();
public static void setCustomerType(String customerType) {
contextHolder.set(customerType);
}
public static String getCustomerType() {
String manager = (String)FacesContext.getCurrentInstance().getExternalContext().getSessionMap().get("dataBaseManager");
if (manager != null) {
contextHolder.set(manager);
FacesContext.getCurrentInstance().getExternalContext().getSessionMap().put("dataBaseManager", null);
} else {
String base = (String)FacesContext.getCurrentInstance().getExternalContext().getSessionMap().get("currentDatabBase");
if (base != null)
contextHolder.set(base);
}
return (String) contextHolder.get();
}
public static void clearCustomerType() {
contextHolder.remove();
}
}
The problem is that the last guy is calling FacesContext.getCurrentInstance() to get the servlet context. Just to explain, it uses the session Attribute dataBaseManager to tell which base it should use.
For the actual solution it was working fine, but with the implementation of a RESTEASY web service, when we make a get request the FacesContext.getCurrentInstance() is obviously returning null and crashing.
I searched a lot and could not find a way of getting the servlet-context from outside of the #GET params. I would like to know if is there any way of getting it, or if there is another solution for my dynamic datasource problem.
Thanks!
Like magic and probably not much people know.
I searched deep into the Resteasy documentation, and found a part of springmvc plugin that comes with the resteasy jars, that has a class called RequestUtil.class.
With that I was able to use the method getRequest() without the "#Context HttpServletRequest req" param.
Using that I was able to set the desired database on the request attributes, and from another thread (called by spring) get it and load the stuff from the right place!
I'm using it for a week now and it works like a charm. Only thing that I needed to do is change the determineLookupKey() above to this:
#Override
protected String determineCurrentLookupKey() {
if (FacesContext.getCurrentInstance() == null) {
//RESTEASY
HttpServletRequest hsr = RequestUtil.getRequest();
String lookUpKey = (String) hsr.getAttribute("dataBaseManager");
return lookUpKey;
}else{
//JSF
return CustomerContextHolder.getCustomerType();
}
}
Hope this helps other people!
Thiago

Resources