I have implemented a reverse proxy with Undertow server.
I want to edit the absolute URLs in the response from target host before sending back to client.
I've used exchange.addResponseCommitListener(httpHandler) so that exchange object contains response from the proxied server and the response hasn't been sent to the client yet.
In httpHandler, I'm able to see the exact length of the proxied response with exchange.getResponseContentLength() but unable to find any function that reads the response data.
I've checked the implementation of exchange.getResponseContentLength() but its only giving the value from one of response headers Content-Length.
Can anyone please help me how to retrieve the response data that has been proxied. Thanks
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I am trying to read Jira issue data using a webhook that posts the data to my servlet.
When I travserve the request parameters map, I don't find anything in it.
But the content lenght shows as "8876" which means webhook is sending the data. Somehow I am not able to read/retrieve the data in my servlet.
Also checked, content-type returns as "application/json".
Does anyone know how to read Jira webhook post data?
You have to read the response body, not the parameters map. For that purpose you can use
request.getInputStream();
or
request.getReader();
method.
PS: You can configure the web hook to post data to http://requestb.in/ so you can easily analyze the request parameters, the request body, the headers, etc.
I am writing one client to measure Jersey, REST based web service performance. I have written some code to measure response time and to measure number of bytes sent from the server but response.getLength() method always returning -1.
In many QA forum I read that setting client.setChunkedEncodingSize(null) will work but even after setting this, I am getting -1.
From server side, I am sending response of type XML or JSON or protobuf depending upon parameters sent by client. For all of these response types, I am getting response length as -1.
My actual request looks like below:
WebResource webResourceQuery = client.resource(requestUrl);
ClientResponse response = webResourceQuery.header("Authorization", header)
.accept(MediaType.APPLICATION_JSON)
.get(ClientResponse.class);
From server side, I am not setting content-length explicitly. Can anyone please help me in getting content-length on client side?
Whole purpose of this experiment is to measure which response type is more efficient in terms of response time and amount of data sent/received.
I ran in to the same problem: client.setChunkedEncodingSize(null); does not work.
This worked for me to actually disable chunked encoding:
client.getProperties().put(ApacheHttpClient4Config.PROPERTY_ENABLE_BUFFERING, true);
Is it possible to send HTTP POST request to a webserver and retrieve just headers of response or read just few bytes of the body, so the rest won't be downloaded at all (so it won't consume traffic)? If yes, how?
I know that there is a HEAD method for this, but I need to achieve it by POST method .. well, I am not sure if I need the POST method, I just need to post the data. Maybe if the webserver isn't secured well enough (it doesn't check what method it's used - it's just directly access the post data), is it possible to send "post data" by HEAD request?
There is no built-in HTTP mechanism for this, and HTTP HEAD requests do not allow content in the body. If however you are the one writing the server code then anything is possible.
If this is the case, I would suggest a URL parameter that triggers this behavior. For example:
POST /myURL - This would return the whole response
POST /myURL?body=minimal - Returns the reduced size response that you are looking for.
And you would have to code your server method to construct and return the appropriate response based on the URL parameter.
I have a client who is posting some data to our server with http POST method. Our server is resin 3.0 with java. When I send response whether data is saved or not the the content length of the response is not set. client is using curl library(php wrapper over it) and they are receiving content length as 0. When I try to submit a form through a browser to our server on the same url it works and response is shown.
I tried using Apache HttpClient to submit data through postmethod and I received content length as -1 but i did get the full response. I'm not able to understand where is the problem. Also I did some google and found that resin do some chunked encoding while sending the response. But i guess it does this also for GET method. But for GET method my client is getting the content length and is able to get the response as well. Need help with this.
"Content-Length" is a header in the response, which warns the client on how big the response will be. It is not the actual length of the stream.
You can set it's value with response.setContentLength(...); in your Servlet.
im writing a java application that sends a post request to a server and expect a json from the server. Now when i need to get the response from the server do i only need to get it from the inputStream when the http code is 200 (HTTP OK) or is there any other cases ? , example :
//...
if (urlConn.getResponseCode() == HttpURLConnection.HTTP_OK) {
// only here try to get the response
}
//...
It depends on how the server is implemented. Check the API, if the server has one. If it's internal, ask your server guy.
Generally speaking, if your response code is either 2xx or 3xx, I would check the response anyway...
If the server your communicating with is following the spec then either 200 or 201 responses are valid to contain an entity. A 204 response is successful but has no data in the response.
See section 9.5 here: http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.5 for details of acceptable responses to a POST. Extract below:
The action performed by the POST method might not result in a resource
that can be identified by a URI. In this case, either 200 (OK) or 204
(No Content) is the appropriate response status, depending on whether
or not the response includes an entity that describes the result.
If a resource has been created on the origin server, the response
SHOULD be 201 (Created) and contain an entity which describes the
status of the request and refers to the new resource, and a Location
header (see section 14.30).
There are three things to consider:
All 2xx codes denote success of some sort. But depending on the exact code, your reading code might be different. (204 for example means success but no content.)
There are redirecting codes (3xx). These are usually automatically followed by the http client library but you can also set them not to, in which case you need to have custom code that handles these cases.
There can be valuable information returned in the stream even if you get a code that denotes an error. Whether you want to process it depends on your exact needs.