I'm trying to make a POST call to an api through WebClient without a request body (the api does not need a body):
webClient.post()
.uri("url")
.retrieve()
.bodyToMono(CustomResponse.class);
But the call returns an exception:
The underlying HTTP client completed without emitting a
response.java.lang.IllegalStateException: The underlying HTTP client
completed without emitting a response.
For another API which requires a request body, I can successfully make a POST call with no issue:
webClient.post()
.uri("url")
.bodyValue("value")
.retrieve()
.bodyToMono(CustomResponse.class);
Is the problem related to the WebClient’s request body? How do I fix it?
UPDATE
The error happens because I added a ContentType header for Webclient through .defaultHeader("ContentType", JSON).
The problem has gone after I've removed the header.
It looks like the downstream webservice responding too slow and exceeding connection timeout hence you're getting this issue.
In case you don't need (or response doesn't have body) you can use .toBodilessEntity() instead. So you code snippet can be rewritten:
webClient.post()
.uri("url")
.retrieve()
.toBodilessEntity();
Why should you use it? Because you're always responsible for resources release. Please, read NOTE section.
When using exchange(), it is the responsibility of the application to
consume any response content regardless of the scenario (success,
error, unexpected data, etc). Not doing so can cause a memory leak.
See ClientResponse for a list of all the available options for
consuming the body.
Related
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
HTTP GET with request body
I've read few discussions here which do not advocate sending content via HTTP GET. There are restrictions on the size of data that can be sent via clients (web browsers). And handling GET data also depends on servers. Please refer section Resources below.
However, I've been asked to test the possibility to send content via HTTP GET using RestTemplate. I refered few discussions on spring forum but they were not answered. (Please note sending data via http Post works fine). The discussion here suggests using POST instead.
dev env - JBoss AS 5.1, Spring 3.1.3
Client
#Test
public void testGetWithBody()
{
// acceptable media type
List<MediaType> acceptableMediaTypes = new ArrayList<MediaType>();
acceptableMediaTypes.add(MediaType.TEXT_PLAIN);
// header
HttpHeaders headers = new HttpHeaders();
headers.setAccept(acceptableMediaTypes);
// body
String body = "hello world";
HttpEntity<String> entity = new HttpEntity<String>(body, headers);
Map<String, Object> uriVariables = new HashMap<String, Object>();
uriVariables.put("id", "testFile");
// Send the request as GET
ResponseEntity<String> result = restTemplate.exchange(
"http://localhost:8080/WebApp/test/{id}/body",
HttpMethod.GET, entity, String.class, uriVariables);
Assert.assertNotNull(result.getBody());
}
Server #Controller
#RequestMapping(value = "/{id}/body", method = RequestMethod.GET)
public #ResponseBody
String testGetWithBody(#PathVariable String id,
#RequestBody String bodyContent)
{
return id + bodyContent;
}
The problem -
executing this test case returns 500 Internal Server Error. On debugging, I found that the controller is not hit.
Is it correct to understand that the RestTemplate provides the way to send data as request body, but the error occurs because the server could not handle the request body ?
If the request body sent via HTTP Get is not conventional why does RestTemplate provide the APIs to allow sending it ? Does this mean there are few servers capable of handling the Request body via GET ?
Resources - discussions on sending body via HTTP GET using RestTemplate at spring forum
http://forum.springsource.org/showthread.php?129510-Message-body-with-HTTP-GET&highlight=resttemplate+http+get
http://forum.springsource.org/showthread.php?94201-GET-method-on-RestTemplate-exchange-with-a-Body&highlight=resttemplate+http+get
Resources - General discussions on sending body via HTTP GET
get-with-request-body
is-this-statement-correct-http-get-method-always-has-no-message-body
get-or-post-when-reading-request-body
http-uri-get-limit
Is it correct to understand that the RestTemplate provides the way to send data as request body, but the error occurs because the server could not handle the request body ?
You can tell by looking at network traffic (does the request get sent with a request body and a GET method?) and at server logs (the 500 result you receive must have a server-side effect that gets logged, and if not, configure the server to do so).
If the request body sent via HTTP Get is not conventional why does RestTemplate provide the APIs to allow sending it ? Does this mean there are few servers capable of handling the Request body via GET ?
Because it is a generic class that also allows you to craft requests that can include a message body.
As stated in HTTP GET with request body:
In other words, any HTTP request message is allowed to contain a message body, and thus [a server] must parse messages with that in mind. Server semantics for GET, however, are restricted such that a body, if any, has no semantic meaning to the request. The requirements on parsing are separate from the requirements on method semantics.
A body on a GET cannot do anything semantically, because you are requesting a resource. It's like you tell the server: "Give me resource X, oh, and have some apples!". The server won't care about your apples and happily serve resource X - or throw an error because it doesn't like any offers in a request.
However, I've been asked to test the possibility to send content via HTTP GET
Please tell the one who requested this that this is a case that should not have to be tested, because no sensible implementation supports it.
I'm trying to read a JSON response from a RESTful webserver running on an IoT module (Advantech WISE-4012). According to the documentation, any GET request should be made in this form
GET /ai_value/slot_0/ch_0
Any Java implementation of GET requests (Java libraries, Apache etc.), anyway, append to the end of the request the protocol signature HTTP/1.1. E.g:
GET http://192.168.0.14/ai_value/slot_0/ch_0 HTTP/1.1
Because of this (probably) i'm getting Error 400 (Bad request) on every client i tried so far. The only working method i've discovered was sending a simple request through the address bar on Google Chrome browser (sometimes i get a response, sometimes a get a bad request error either). How can i write a java implementation of a GET request plain and simple as described by the documentation? How can i test a custom GET request without HTTP/1.1 at the end? Every chrome extension i tried (Advanced REST Client, Postman) add the protocol version at the end, so i haven't had the chance to verify if that's why i'm getting a bad request error.
EDIT:
This is the response header from Advanced REST client
Connection: close
Content-Type: application/json
Server: WISE-4000/8.1.0020
While the source message is the following one:
GET /ai_value/slot_0/ch_0 HTTP/1.1
HOST: 192.168.0.14
The only mismatch between the documentation is the HTTP/1.1 signature as mentioned before. Adding the "accept: application/json" makes no difference either
After a bit of digging into the documentation, it looks like the default timeout (i.e. 720 seconds) is the one causing an issue. There doesn't seem to be any way to work it around (ideally, the system should reset the time after a successful request and we should only get 400 - or 403 ideally after 720 seconds of inactivity).
A couple of points I would like to recommend to the API developers for WISE-4012 (if they are in touch with you):
Add brief documentation for authentication and timeout (probably, more response codes and error messages with each error response)
Enable OAuth for API Access
As far as current implentation is conerned, I guess you need to do a basic auth and pass username/password with every request, Or add Authentication header with every API request to get successful response without any 400s.
Check if this helps.
HttpClient httpClient = HttpClients.createDefault();
URI reqUri = new URI(<uri>);
RequestBuilder requestBuilder = RequestBuilder.create("GET");
requestBuilder.setUri(reqUri);
requestBuilder.setHeader(<headerKey>, <headerValue>);
requestBuilder.setEntity(<entity_data>);
HttpUriRequest httpRequest = requestBuilder.build();
httpResponse = httpClient.execute(httpRequest);
Would you please advise how to configure RestAssured to wait until complete response data is returned.
I am trying to validate a data feed using http get as shown below.
given()
.relaxedHTTPSValidation()
.header("Content-Type", "application/json")
.when()
.get("/API/data/")
.then()
.statusCode(200)
.log().all();
In this context, Rest Assured logging only few lines of data, does not seem to wait until complete response data is returned .
This works ok when data response is small.
In this case, it seems to log only data that's available when http status code is returned.
Consequently I am seeing the following error message: Premature end of Content-Length delimited message body (expected: 1486; received: 1088)
Thx
If you want to check the status code you should use the expect().statusCode(x).
Anyway the tool waits until the whole response is returned from the server and only logs it out after that. So it shouldn't be a problem with big JSON/XML responses either.
I have to invoke several webservices using WS-Addressing.
When invoking a webservice, the ReplyTo is set to a callback endpoint implemented by me.
The client is generated from the target WSDL using async with
<enableAsyncMapping>true</enableAsyncMapping>
which generates the Async version for each webservice with the following signature:
javax.xml.ws.Response<SampleWebServiceOutput> sampleWebService(SampleWebServiceInput input)
When invoking sampleWebService like,
Response<SampleWebServiceOutput> response = clientWsPort.sampleWebService(input);
if the request is sucessful, the server will return 202 Accepted however I can't figure out how to get it.
If I use response.get(), it will block forever since the response is sent to my callback url (WSA-Addressing Reply To)
Any clues how to know for sure if the server successfully accepted the request ?
Thank you.
Apparently the response returned when you set a different reply-to address results in a null response, which could explain why it is hanging when you call response.get().
The recommended solution is to use something like getResponseContext(), which is called from the binding.
I need to check response header of HTTP request using OkHTTP library. before loading data I need to check it's last update time. The problem in that that the response body is about 2 MB so I need to get only Last-Modified header. Is it possible to load only response header without response body to increase the speed of the program`s RESTful actions?
You can send a HTTP HEAD request which only retrieves the headers. You only need to check if your server application supports HEAD requests.
The HEAD method is identical to GET except that the server MUST NOT
return a message-body in the response. The metainformation contained
in the HTTP headers in response to a HEAD request SHOULD be identical
to the information sent in response to a GET request. This method can
be used for obtaining metainformation about the entity implied by the
request without transferring the entity-body itself. This method is
often used for testing hypertext links for validity, accessibility,
and recent modification. (http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html)
Example for OkHttp:
String url = ...
Request request = new Request.Builder().url(url).head().build();
The response body is streamed, so you can make the regular request, read the headers, and then decide whether or not to consume the body. If you don’t want the body, you can close() it without much waste.
There is a slight cost to the server to serve a response that might be abandoned. But the overall cost will be lower than making a HEAD and then a GET request unless you expect abandon a significant fraction (say > 90%) of requests.