I'm looking for a way to copy some headers from the request message to the response message when I use RabbitMq in RPC mode.
so far I have tried with setBeforeSendReplyPostProcessors but I can only access the response and add headers to it. but I don't have access to the request to get the values I need.
I have also tried with the advice chain, but the returnObject is null after proceeding so I can't modify it (I admit I don't understand why it is null... I thought I could get the object to modify it):
#Bean
public SimpleRabbitListenerContainerFactory simpleRabbitListenerContainerFactory(SimpleRabbitListenerContainerFactoryConfigurer simpleRabbitListenerContainerFactoryConfigurer, ConnectionFactory connectionFactory) {
SimpleRabbitListenerContainerFactory simpleRabbitListenerContainerFactory = new SimpleRabbitListenerContainerFactory();
simpleRabbitListenerContainerFactory.setAdviceChain(new MethodInterceptor() {
#Override
public Object invoke(MethodInvocation invocation) throws Throwable {
Object returnObject = invocation.proceed();
//returnObject is null here
return returnObject;
}
});
simpleRabbitListenerContainerFactoryConfigurer.configure(simpleRabbitListenerContainerFactory, connectionFactory);
return simpleRabbitListenerContainerFactory;
}
a working way is to change my method annotated with #RabbitListener so it returns a Message and there I can access both the requesting message (via arguments of the annotated method) and the response.
But I would like to do it automatically, since I need this feature at different places.
Basicaly I want to copy one header from the request message to the response.
this code do the job, but I want to do it through an aspect, or an interceptor.
#RabbitListener(queues = "myQueue"
, containerFactory = "simpleRabbitListenerContainerFactory")
public Message<MyResponseObject> execute(MyRequestObject myRequestObject, #Header("HEADER_TO_COPY") String headerToCopy) {
MyResponseObject myResponseObject = compute(myRequestObject);
return MessageBuilder.withPayload(myResponseObject)
.setHeader("HEADER_RESPONSE", headerToCopy)
.build();
}
The Message<?> return type support was added for this reason, but we could add an extension point to allow this, please open a GitHub issue.
Contributions are welcome.
Related
I'd like to create a Spring WebClient that ignores a specific HTTP error. From the documentation of WebClient.retrieve():
By default, 4xx and 5xx responses result in a WebClientResponseException. To customize error handling, use ResponseSpec.onStatus(Predicate, Function) handlers.
I want all calls through a WebClient instance to ignore the specific HTTP error. That is why onStatus() is of no use to me (it has to be set per response).
The best I could come up with is this:
WebClient webClient = WebClient.builder().filter((request, next) -> {
Mono<ClientResponse> response = next.exchange(request);
response = response.onErrorResume(WebClientResponseException.class, ex -> {
return ex.getRawStatusCode() == 418 ? Mono.empty() : Mono.error(ex);
});
return response;
}).build();
URI uri = UriComponentsBuilder.fromUriString("https://httpstat.us/418").build().toUri();
webClient.get().uri(uri).retrieve().toBodilessEntity().block();
but it does throw the exception instead of ignoring it (the lambda passed to onErrorResume() is never called).
Edited: fixed the mistake pointed out by the first answer.
After extensive debugging of spring-webflux 5.3.4 and with the help of some ideas by Martin Tarjányi, I've come to this as the only possible "solution":
WebClient webClient = WebClient.builder().filter((request, next) -> {
return next.exchange(request).flatMap(res -> {
if (res.rawStatusCode() == HttpStatus.I_AM_A_TEAPOT.value()) {
res = res.mutate().rawStatusCode(299).build();
}
return Mono.just(res);
});
}).build();
URI uri = UriComponentsBuilder.fromUriString("https://httpstat.us/418").build().toUri();
String body = webClient.get().uri(uri).retrieve().toEntity(String.class).block().getBody();
The background: I am migrating some code from RestTemplate to WebClient. The old code looks like this:
RestTemplate restTemplate = ...;
restTemplate.setErrorHandler(new DefaultResponseErrorHandler() {
#Override
public void handleError(ClientHttpResponse response) throws IOException {
if (response.getRawStatusCode() == HttpStatus.I_AM_A_TEAPOT.value()) {
return;
}
super.handleError(response);
}
});
URI uri = UriComponentsBuilder.fromUriString("https://httpstat.us/418").build().toUri();
String body = restTemplate.getForEntity(uri, String.class).getBody();
I believe it is a straightforward and common case.
WebClient is not yet a 100% replacement for RestTemplate.
UPDATE: Turns out this answer doesn't address the core problem of filtering out a specific status code, just addresses a general coding pattern.
The reason onErrorResume lambda is not called is that response.onErrorResume creates a brand new Mono and your code does not use the result (i.e. it's not assigned to the response variable), so in the end a Mono without the onErrorResume operator is returned.
Using Project Reactor it's usually a good practice to avoid declaring local Mono and Flux variables and use a single chain instead. This helps to avoid similar subtle bugs.
WebClient webClient = WebClient.builder()
.filter((request, next) -> next.exchange(request)
.onErrorResume(WebClientResponseException.class, ex -> ex.getRawStatusCode() == 418 ? Mono.empty() : Mono.error(ex)))
.build();
I am working on a usecase where I am supposed to poll S3 -> read the stream for the content -> do some processing and upload it to another bucket rather than writing the file in my server.
I know I can achieve it using S3StreamingMessageSource in Spring aws integration but the problem I am facing is that I do not know on how to process the message stream received by polling
public class S3PollerConfigurationUsingStreaming {
#Value("${amazonProperties.bucketName}")
private String bucketName;
#Value("${amazonProperties.newBucket}")
private String newBucket;
#Autowired
private AmazonClientService amazonClient;
#Bean
#InboundChannelAdapter(value = "s3Channel", poller = #Poller(fixedDelay = "100"))
public MessageSource<InputStream> s3InboundStreamingMessageSource() {
S3StreamingMessageSource messageSource = new S3StreamingMessageSource(template());
messageSource.setRemoteDirectory(bucketName);
messageSource.setFilter(new S3PersistentAcceptOnceFileListFilter(new SimpleMetadataStore(),
"streaming"));
return messageSource;
}
#Bean
#Transformer(inputChannel = "s3Channel", outputChannel = "data")
public org.springframework.integration.transformer.Transformer transformer() {
return new StreamTransformer();
}
#Bean
public S3RemoteFileTemplate template() {
return new S3RemoteFileTemplate(new S3SessionFactory(amazonClient.getS3Client()));
}
#Bean
public PollableChannel s3Channel() {
return new QueueChannel();
}
#Bean
IntegrationFlow fileStreamingFlow() {
return IntegrationFlows
.from(s3InboundStreamingMessageSource(),
e -> e.poller(p -> p.fixedDelay(30, TimeUnit.SECONDS)))
.handle(streamFile())
.get();
}
}
Can someone please help me with the code to process the stream ?
Not sure what is your problem, but I see that you have a mix of concerns. If you use messaging annotations (see #InboundChannelAdapter in your config), what is the point to use the same s3InboundStreamingMessageSource in the IntegrationFlow definition?
Anyway it looks like you have already explored for yourself a StreamTransformer. This one has a charset property to convert your InputStreamfrom the remote S3 resource to the String. Otherwise it returns a byte[]. Everything else is up to you what and how to do with this converted content.
Also I don't see reason to have an s3Channel as a QueueChannel, since the start of your flow is pollable anyway by the #InboundChannelAdapter.
From big height I would say we have more questions to you, than vise versa...
UPDATE
Not clear what is your idea for InputStream processing, but that is really a fact that after S3StreamingMessageSource you are going to have exactly InputStream as a payload in the next handler.
Also not sure what is your streamFile(), but it must really expect InputStream as an input from the payload of the request message.
You also can use the mentioned StreamTransformer over there:
#Bean
IntegrationFlow fileStreamingFlow() {
return IntegrationFlows
.from(s3InboundStreamingMessageSource(),
e -> e.poller(p -> p.fixedDelay(30, TimeUnit.SECONDS)))
.transform(Transformers.fromStream("UTF-8"))
.get();
}
And the next .handle() will be ready for String as a payload.
Class is defined as follows:
public class BizTalkRESTTransmitHandler : IClientMessageInspector
I'm a method with this signature:
public object BeforeSendRequest(ref Message request, IClientChannel channel)
So I think I need to manipulate the channel object.
The reason is this is being using in BizTalk 2010 SendPort to support JSON.
I tried this so far:
if (channel.RemoteAddress.Uri.AbsoluteUri == "http://api-stage2.mypartner.com/rest/events/2/"
|| channel.RemoteAddress.Uri.AbsoluteUri == "http://api.mypartner.com/rest/events/2/")
{
//TODO - "boxout" will become a variable obtained by parsing the message
Uri newUri = new Uri(channel.RemoteAddress.Uri.AbsoluteUri + "boxout");
channel.RemoteAddress.Uri = newUri;
}
Above gives compile error: "System.ServiceModel.EndpointAddress.Uri" cannot be assigned to - it is ready only" RemoteAddress seems to be read only as well.
I have referenced these questions but they don't use channel object.
Assign a URL to Url.AbsoluteUri in ASP.NET, and
WCF change endpoint address at runtime
But they don't seem to be dealing with channel object.
Update 1: I tried the following:
//try create new channel to change URL
WebHttpBinding myBinding = new WebHttpBinding();
EndpointAddress myEndpoint = new EndpointAddress(newURL);
ChannelFactory<IClientChannel> myChannelFactory = new ChannelFactory<IClientChannel>(myBinding, myEndpoint); //Change to you WCF interface
IClientChannel myNewChannel = myChannelFactory.CreateChannel();
channel = myNewChannel; //replace the channel parm passed to us
but it gave this error:
System.InvalidOperationException: Attempted to get contract type for IClientChannel, but that type is not a ServiceContract, nor does it inherit a ServiceContract.
IClientMessageInspector is not the right place the manipulate the Channel, you should use IEndpointBehavior instead:
From MSDN
Implements methods that can be used to extend run-time behavior for an
endpoint in either a service or client application.
Here is a simple example:
public void ApplyDispatchBehavior(ServiceEndpoint endpoint, EndpointDispatcher endpointDispatcher)
{
Uri endpointAddress = endpoint.Address.Uri;
string address = endpointAddress.ToString();
if (address == "http://api-stage2.mypartner.com/rest/events/2/"
|| address == "http://api.mypartner.com/rest/events/2/")
{
//TODO - "boxout" will become a variable obtained by parsing the message
Uri newUri = new Uri(address + "boxout");
ServiceHostBase host = endpointDispatcher.ChannelDispatcher.Host;
ChannelDispatcher newDispatcher = this.CreateChannelDispatcher(host, endpoint, newUri);
host.ChannelDispatchers.Add(newDispatcher);
}
}
Here you can read the excelent post of Carlos Figueira about IEndpointBehavior:
https://blogs.msdn.microsoft.com/carlosfigueira/2011/04/04/wcf-extensibility-iendpointbehavior/
Another alternative is to implement a simple Routing with WCF, here is link with an example:
WCF REST service url routing based on query parameters
Hope it helps.
Using the interface IEndpointBehavior, you'll have access to the ApplyClientBehavior method, which exposes the ServiceEndPoint instance.
Now you can change the value for the Address by defining a new EndpointAddress instance.
public class MyCustomEndpointBehavior : IEndpointBehavior
{
public void AddBindingParameters(ServiceEndpoint serviceEndpoint, System.ServiceModel.Channels.BindingParameterCollection bindingParameters)
{
}
public void ApplyClientBehavior(ServiceEndpoint serviceEndpoint, System.ServiceModel.Dispatcher.ClientRuntime behavior)
{
serviceEndpoint.Address = new System.ServiceModel.EndpointAddress("http://mynewaddress.com");
}
public void ApplyDispatchBehavior(ServiceEndpoint serviceEndpoint, System.ServiceModel.Dispatcher.EndpointDispatcher endpointDispatcher)
{
}
public void Validate(ServiceEndpoint serviceEndpoint)
{
}
}
I might be a bit too late but hoe it helps a bit.
I recently had a similar objective (also related to biztalk) where I needed to change the url based on some value sent on the message.
I tried using the ApplyDispatchBehavior method but it was never called and also, I couldn't see how to access the message from here so I started looking at method BeforeSendRequest (in the Inspector class).
Here is what i came up with:
object IClientMessageInspector.BeforeSendRequest(ref Message request, IClientChannel channel)
{
var queryDictionary = HttpUtility.ParseQueryString(request.Headers.To.Query);
string parameterValue = queryDictionary[this.BehaviourConfiguration.QueryParameter];
//Only change parameter value if it exists
if (parameterValue != null)
{
MessageBuffer buffer = request.CreateBufferedCopy(Int32.MaxValue);
request = buffer.CreateMessage();
//Necessary in order to read the message without having WCF throwing and error saying
//the messas was already read
var reqAux = buffer.CreateMessage();
//For some reason the message comes in binary inside tags <Binary>MESSAGE</Binary>
using (MemoryStream ms = new MemoryStream(Convert.FromBase64String(reqAux.ToString().Replace("<Binary>", "").Replace("</Binary>", ""))))
{
ms.Position = 0;
string val = ExtractNodeValueByXPath(ms, this.BehaviourConfiguration.FieldXpath);
queryDictionary.Set(this.BehaviourConfiguration.QueryParameter, DateTime.Now.ToString("yyyyMMddHHmmssfff") + "_" +
this.BehaviourConfiguration.Message + (string.IsNullOrWhiteSpace(val) ? string.Empty : "_" + val) + ".xml");
UriBuilder ub = new UriBuilder(request.Headers.To);
ub.Query = queryDictionary.ToString();
request.Headers.To = ub.Uri;
}
}
return null;
}
So, I discovered that, messing with the request.Headers.To I could change the endpoint.
I had several problems getting the message content and most examples on the internet (showing to use the MessageBuffer.CreateNavigator or Message.GetBody< string > which was always throwing an expcetion i couldn't get around) would not give me the biztalk message but rather the soap message?... not sure but it had a node header, body and inside the body there was some base64 string which was not my biztalk message.
Also, as you can see in Convert.FromBase64String(reqAux.ToString().Replace("<Binary>", "").Replace("</Binary>", "")), I had to do this ugly replaces. I don't don't why this comes in base64, probably some WCF configuration?, but by doing it, I could then look for my value.
NOTE: I haven't fully tested this, but so far it as worked for my examples.
By the way, any idea on what can i switch my MemoryStream with so it becomes a more streaming solution?
Using NServiceBus 4.0.11
I would like to call
Bus.OutgoingHeaders["user"] = "john";
The Header Manipulation sample shows how to call it with a custom host.
I would like to call it while using the NServiceBus.Host.
So actually I would like to have a reference to the instance of the Bus, to call OutgoingHeaders on.
Tried IWantCustomInitialization but that gives me an exception when calling CreateBus in it. INeedInitialization isn't the way to go neither.
How should I call Bus.OutgoingHeaders["user"] = "john"; while using the NServiceBus.Host?
Reading your question makes me think that you want to add this header to a certain message that you want to send during initialization/startup or when handling a message. Usually, headers have a more generic behavior as they need to be applied to more than one message.
Instead of setting the header before sending the message you can also add the header via a message mutator or behavior.
Behavior
public class OutgoingBehavior : IBehavior<SendPhysicalMessageContext>
{
public void Invoke(SendPhysicalMessageContext context, Action next)
{
Dictionary<string, string> headers = context.MessageToSend.Headers;
headers["MyCustomHeader"] = "My custom value";
next();
}
}
Mutator
public class MutateOutgoingTransportMessages : IMutateOutgoingTransportMessages
{
public void MutateOutgoing(object[] messages, TransportMessage transportMessage)
{
Dictionary<string, string> headers = transportMessage.Headers;
headers["MyCustomHeader"] = "My custom value";
}
}
Documentation
See: http://docs.particular.net/nservicebus/messaging/message-headers#replying-to-a-saga-writing-outgoing-headers for samples.
I am working on the Jboss Resteasy API to implement the REST services on Jboss server.I am new to this area. Can someone help me out here...
There is a Rest Service method with custom annotation(VRestAuto) like below.
#POST
#Produces("text/json")
#Path("/qciimplinv")
#Interceptors(VRestInterceptor.class)
public String getInvSummary(#VRestAuto("EnterpriseId") String enterpriseId,String circuitType){
....
businessMethod(enterpriseId,circuitType);
....
}
#VRestAuto annotation tell us 'enterpriseId' value is available in the user session.
User pass the circuitType alone as the POST parameter in the Rest Client tool.Should ideally read the enterpriseid from session and invoke the Rest service with these two parameters(enterpriseid,circuitType).
To achieve the above functionality, implemented the Interceptors class (VRestInterceptor) like below:
public class VRestInterceptor implemnets PreProcessInterceptor,AcceptedByMethod {
public boolean accept(Class declaring, Method method) {
for (Annotation[] annotations : method.getParameterAnnotations()) {
for (Annotation annotation : annotations) {
if(annotation.annotationType() == VRestAuto.class){
VRestAuto vRestAuto = (VRestAuto) annotation;
return vRestAuto.value().equals("EnterpriseId");
}
}
}
return false;
}
Override
public ServerResponse preProcess(HttpRequest request, ResourceMethod method)
throws Failure, WebApplicationException { ......}
}
I was able to verify the VRestAuto annotation in the accept method. But in the preProcess Method, how can I call the REST method with two parameters(enterpriseid, circuitType)?
if these interceptors are not suits, Are there any other interceptors best to this functionality?
Your help is highly appreciated .
Why not forget setting the enterpriseId value when the method is called and instead just inject the HttpServletRequest and use that to grab the session and value?
#POST
#Produces("text/json")
#Path("/qciimplinv")
public String getInvSummary(String circuitType, #Context HttpServletRequest servletRequest) {
HttpSession session = servletRequest.getSession();
String enterpriseId = session.getAttribute("EnterpriseId").toString();
....
businessMethod(enterpriseId,circuitType);
....
}