When I execute HttpWebRequest.GetResponse on URL, GetResponse returns "The remote server returned an error: (400) Bad Request." instead of response.
The strange thing is that when I run this url at the browser I get the right response.
doesn't webrequest need to return the same values as the browser?
the following code return bad request
// Create a request for the URL.
WebRequest request = WebRequest.Create(
"http://someUrl/api/v5/basicAuth");
// Get the response.
WebResponse response = request.GetResponse();
// Display the status.
Console.WriteLine(((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
Stream dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd();
// Display the content.
Console.WriteLine(responseFromServer);
// Clean up the streams and the response.
reader.Close();
response.Close();
also tried using WebClient with same results.
any idea how to get the proper response same as the browser?
The title says you're getting a 400 bad request, but in your question you say 404 Not Found. Those are very different. For a 404, I'd be troubleshooting the URL itself and how the request is being routed, DNS, etc. if it's a 400, then I would use something like Fiddler to capture how my request looks when using a browser, then see what the request looks like when coming from the program and see what's different/missing. It could be that some HTTP headers are needed, such as the content-type, or handling of cookies, etc etc. But something like Fiddler could at least get you started.
I'm having problems setting cookies in a custom http module. I'm handling the BeginRequest event and setting the cookie along these lines:
HttpCookie myCookie = new HttpCookie(config.CookieName);
SitePrefCookie["key1"] = value1;
SitePrefCookie["key2"] = value2;
SitePrefCookie.Expires = DateTime.Now.AddDays(365);
SitePrefCookie.Domain = myDomain;
SitePrefCookie.Path = "/";
HttpContext.Current.Response.Cookies.Add(SitePrefCookie);
I know there's nothing wrong with the cookie itself, because it will work if I call Response.Flush() or set the status to 302 (as it's a http module for redirecting). But I can't do both in one request, i.e. flush and then redirect because ASP.Net will complain about headers already being sent to the client.
I'm sure I can work around this weird limitation, but I just don't understand why the cookie is not even being sent back in the response in a scenario that doesn't require a redirect or flushing of the response.
This is a known issue. See http://support.microsoft.com/kb/2666571 for details and a workaround.
I have been toiling over HttpURLConnection and setRequestProperty for 2 days so far and I cannot get this webpage to Post and return the page I desire. This is what I have so far...
...
String data = URLEncoder.encode("acctno", "UTF-8") + "=" + URLEncoder.encode("1991462", "UTF-8");
URL oracle = new URL("http://taxinquiry.princegeorgescountymd.gov");
HttpURLConnection yc = (HttpURLConnection) oracle.openConnection();
yc.setRequestMethod("POST");
yc.setRequestProperty("Content-Type", "text/html; charset=utf-8");
yc.setRequestProperty("Content-Length", "19004");
yc.setRequestProperty("Cache-Control", "private");
yc.setRequestProperty("Set-Cookie", "ASP.NET_SessionId=v5rdm145zv3jm545kdslgz55; path=/");
yc.setRequestProperty("X-AspNet-Version", "1.1.4322");
yc.setRequestProperty("X-Powered-By", "ASP.NET");
yc.setRequestProperty("Server", "Microsoft-IIS/6.0");
yc.setDoOutput(true);
yc.setDoInput(true);
OutputStreamWriter out = new OutputStreamWriter(yc.getOutputStream());
out.write(data);
out.flush();
//out.write(data);
out.close();
...
It returns the same page defined in URL. it doesn't send me the requested page which should have an ending /taxsummary.aspx
It looks as if the asp takes the post data and generates an HTML unique for each parameter given. How do I give it the correct parameters?
Your code looks fine. I believe it sends POST correctly. I think that the problem is not here. When you are using browser you first perform at least one HTTP GET to arrive to the form. When you are doing this the server creates HTTP session for you and returns its id in response header Set-Cookie. When you are submitting the form using browser it sends this header (Cookie) back, so the server can identify the session.
When you are working from java you are skipping the first phase (HTTP GET). So the first thing you are doing is POST while you do not have session yet. I do not know what is the logic of this ASP page but I think that it just rejects such requests.
So, first check this guess. You can use plugin to Firefox named LiveHttpHeaders. Install it and perform the operation manually. You will see all HTTP requests and responses. Save them. Check that the session ID is sent back from server to client. Now implement exactly the same in java.
BTW often the situation is event more complicated when server sends multiple redirect responses. Int this case you have to follow them. HttpConnection has method setFollowRedirects(). Call it with parameter true.
BTW2: Apache HttpClient is a perfect replacement to HttpConnection. it does everything and is very recommended when you are implementing such tasks.
That's all. Good luck. Sometimes it is not easy...
I want to post data to another server (JSP or ColdFusion).
Note: Post which means the data is required at the another server also the browser should be redirected automatically.
Is it better to use
form tag...input type hidden fields, values
...
and from javascript
form.submit();
or
HttpWebRequest myRequest =
(HttpWebRequest)WebRequest.Create("http://...");
myRequest.CookieContainer = new System.Net.CookieContainer(10000);
myRequest.Method = "POST";
myRequest.ContentType = "application/x-www-form-urlencoded";
myRequest.ContentLength = data.Length;
Stream newStream = myRequest.GetRequestStream();
newStream.Write(data, 0, data.Length);
newStream.Close();
return myRequest;
or
I should use WebClient class?
Please provide the points from Security view also.
If you want the browser to be correctly sent to the other server, then you should really do this client side - your second option will send the response from the remote server back down to the client, but any links in the HTML that are relative will appear broken, as the user will be attempting to request them from your server.
Also, making the request from the code-behind, you'll be sending the request from your server, without any of the client's cookies, headers, etc for that site (which you won't have access to).
The other issues to consider:
Client may have JavaScript disabled.
If the remote server supports SSL, then you should probably be posting to that.
Doing this client side, you'll be sending all form data to the client initially, and then sending it on to the 3rd party server.
When I call Response.Redirect(someUrl) I get the following HttpException:
Cannot redirect after HTTP headers have been sent.
Why do I get this? And how can I fix this issue?
According to the MSDN documentation for Response.Redirect(string url), it will throw an HttpException when "a redirection is attempted after the HTTP headers have been sent". Since Response.Redirect(string url) uses the Http "Location" response header (http://en.wikipedia.org/wiki/HTTP_headers#Responses), calling it will cause the headers to be sent to the client. This means that if you call it a second time, or if you call it after you've caused the headers to be sent in some other way, you'll get the HttpException.
One way to guard against calling Response.Redirect() multiple times is to check the Response.IsRequestBeingRedirected property (bool) before calling it.
// Causes headers to be sent to the client (Http "Location" response header)
Response.Redirect("http://www.stackoverflow.com");
if (!Response.IsRequestBeingRedirected)
// Will not be called
Response.Redirect("http://www.google.com");
Once you send any content at all to the client, the HTTP headers have already been sent. A Response.Redirect() call works by sending special information in the headers that make the browser ask for a different URL.
Since the headers were already sent, asp.net can't do what you want (modify the headers)
You can get around this by a) either doing the Redirect before you do anything else, or b) try using Response.Buffer = true before you do anything else, to make sure that no output is sent to the client until the whole page is done executing.
A Redirect can only happen if the first line in an HTTP message is "HTTP/1.x 3xx Redirect Reason".
If you already called Response.Write() or set some headers, it'll be too late for a redirect. You can try calling Response.Headers.Clear() before the Redirect to see if that helps.
Just check if you have set the buffering option to false (by default its true). For response.redirect to work,
Buffering should be true,
you should not have sent more data using response.write which exceeds the default buffer size (in which case it will flush itself causing the headers to be sent) therefore disallowing you to redirect.
Using
return RedirectPermanent(myUrl) worked for me
You can also use below mentioned code
Response.Write("<script type='text/javascript'>"); Response.Write("window.location = '" + redirect url + "'</script>");Response.Flush();
There is one simple answer for this:
You have been output something else, like text, or anything related to output from your page before you send your header. This affect why you get that error.
Just check your code for posible output or you can put the header on top of your method so it will be send first.
If you are trying to redirect after the headers have been sent (if, for instance, you are doing an error redirect from a partially-generated page), you can send some client Javascript (location.replace or location.href, etc.) to redirect to whatever URL you want. Of course, that depends on what HTML has already been sent down.
My Issue got resolved by adding the Exception Handler to handle
"Cannot redirect after HTTP headers have been sent". this Error as shown below code
catch (System.Threading.ThreadAbortException)
{
// To Handle HTTP Exception "Cannot redirect after HTTP headers have been sent".
}
catch (Exception e)
{//Here you can put your context.response.redirect("page.aspx");}
I solved the problem using:
Response.RedirectToRoute("CultureEnabled", RouteData.Values);
instead of Response.Redirect.
Be sure that you don't use Responses' methods like Response.Flush(); before your redirecting part.
Error
Cannot redirect after HTTP headers have been sent.
System.Web.HttpException (0x80004005): Cannot redirect after HTTP headers have been sent.
Suggestion
If we use asp.net mvc and working on same controller and redirect to different Action then you do not need to write.. Response.Redirect("ActionName","ControllerName"); its better to use only return RedirectToAction("ActionName"); or return View("ViewName");
The redirect function probably works by using the 'refresh' http header (and maybe using a 30X code as well). Once the headers have been sent to the client, there is not way for the server to append that redirect command, its too late.
If you get Cannot redirect after HTTP headers have been sent then try this below code.
HttpContext.Current.Server.ClearError();
// Response.Headers.Clear();
HttpContext.Current.Response.Redirect("/Home/Login",false);
There are 2 ways to fix this:
Just add a return statement after your Response.Redirect(someUrl);
( if the method signature is not "void", you will have to return that "type", of course )
as so:
Response.Redirect("Login.aspx");
return;
Note the return allows the server to perform the redirect...without it, the server wants to continue executing the rest of your code...
Make your Response.Redirect(someUrl) the LAST executed statement in the method that is throwing the exception. Replace your Response.Redirect(someUrl) with a string VARIABLE named "someUrl", and set it to the redirect location... as follows:
//......some code
string someUrl = String.Empty
.....some logic
if (x=y)
{
// comment (original location of Response.Redirect("Login.aspx");)
someUrl = "Login.aspx";
}
......more code
// MOVE your Response.Redirect to HERE (the end of the method):
Response.Redirect(someUrl);
return;