Getting Filename from virtual URL? - asp.net

I have a URL like "http://www.ti.com/lit/gpn/TPS767D318-Q1"
which is a path eventually being routed to "http://www.ti.com/lit/ds/symlink/tps767d318-q1.pdf" on the browser(rendering a pdf file). I am processing this URL in a Console application in order to fetch the "pdf" filename that you see in the second URL i provided.
I checked the UriResponse.Absoluteuri property in the httpresponse object and it says "http://focus.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=TPS767D318-Q1&fileType=pdf"
looks like this is a nested virtual path. Can anybody help on where i can get to the end URL to extract the pdf file name? i did not find it anywhere in the response object. I also checked in the Response headers and nothing there either.
Any help will be appreciated...Thanks

Not sure about ASP, but at the protocol level the initial request may cause a Redirect to be issued by the application/server on the other end, so you can look at the initial HTTP response and check if it's a redirect code, 301, 302 etc. If so, you can follow the 302s until you hit a 200, and that's the final URL you can use to check the filename.

Look at the Content-Disposition header, it might look something like: Content-Disposition: attachment; filename=tps767d318-q1.pdf. This is a common technique for webservices that fetch and "download" files from database, network shares, etc.

It turns out that the URL in my question is actually returning HTML content and doing a "meta tag" redirect. So I had to do the following:
var redirect = Regex.Match(new string(buffer, 0, count), #"\<meta(?=[^>]*http-equiv\W*refresh)[^>]*?content\s*\=[^=>]*url\s*\=\s*(?<Url>[^'"">]+)", RegexOptions.IgnoreCase | RegexOptions.Singleline);
if (redirect.Success)
{
Uri uri = new Uri(new Uri(externalUrl, UriKind.Absolute), new Uri(redirect.Groups["Url"].Value, UriKind.RelativeOrAbsolute));
return SaveUrlToTemporaryFile(uri.AbsoluteUri, needsFullDownload);
}
I'm getting the final URL out of the meta tags from the returned HTML content, and calling my download routine again.

Related

Cannot download with right format an excel file F#

I have the following part of code:
let client = new WebClient()
let url = "https://..."
client.DownloadFile(Url, filename)
client.Dispose()
In which code i am performing a HttpGet method in which method i get a file excel with some data.
The method is executed correctly because i get my excel file.
The problem is that the content of my file excel is like this:
I think its because i don't pass ContentType:"application/vnd.ms-excel"
So anyone can help how can I pass that ContentType in my Client in F# ?
If you want to add HTTP headers to a request made using WebClient, use the Headers property:
let client = new WebClient()
let url = "https://..."
client.Headers.Add(HttpRequestHeader.Accept, "application/vnd.ms-excel")
client.DownloadFile(Url, filename)
In your case, I think you need the Accept header (Content-Type is what the response should contain to tell you what you got).
That said, I'm not sure if this is the problem you are actually having - as noted in the comments, your screenshot shows a different file, so it is hard to tell what's wrong with the file you get from the download (maybe it's just somewhere else? or maybe the encoding is wrong?)

how to forward a link with URI to another link with the same URI

My program directs users to a webpage with their username and password. E.g.
http://example.html?username=username&password=password.
Now I created another page in asp.net and I want some code on example.html to redirect the link to http://example.aspx?username=username&password=password.
So what i want is to get the URI from the first url and direct it to the new url by appending the URI.
Any suggestions?
You can grab the querystring in its entirety via
window.location.search
See this with more about that. Using this, you can extract the parameters, append them to a new URL, and render the link, or set
window.location = "example.aspx" + window.location.search
I believe search comes with "?", but I could be wrong. I assume this is an exmaple; note it's not a good practice to pass the password through a querystring as clear text, especially if you are not using HTTPS. It's generally advisable to do a POST operation, not a GET operation with querystring, when it comes to sensitive information.
Use window.location.search to get everything after "?". Then you can just direct the new aspx page using this java script line.
window.location = "example.aspx" + window.location.search

Url Rewriting in asp.net but maintaining the original url

Page aspxHandler = (Page)PageParser.GetCompiledPageInstance(virtualPath, context.Server.MapPath(virtualPath), context);
aspxHandler.PreRenderComplete += AspxPage_PreRenderComplete;
aspxHandler.ProcessRequest(context);
When you call Page.Request.Url after this, you get the Url of the page you rewrote to
...what I'm looking for is to do a rewrite, but for Page.Request.Url to remain as the original url that was passed in. Is that possible?
I had a similar problem using rewriting rules in the web.config. Not sure if this will solve your problem too, but I found that when the url was rewritten, the originally requested URL was accessible through the "HTTP_X_ORIGINAL_URL" server variable.
VB:
string pathAndQuery = Request.ServerVariables.AllKeys.Contains("HTTP_X_ORIGINAL_URL") ? Request.ServerVariables("HTTP_X_ORIGINAL_URL") : Request.Url.PathAndQuery
c#:
string pathAndQuery = Request.ServerVariables.AllKeys.Contains("HTTP_X_ORIGINAL_URL") ? Request.ServerVariables["HTTP_X_ORIGINAL_URL"] : Request.Url.PathAndQuery;
That should get you the original path and querystring of the request before rewriting, whether or not rewriting has taken place.

Checking The Date A Webpage Has Been Updated?

I want to be able to run a little script that I can populate with a list of URLs and it pulls in and checks when the page was last updated? Has anyone done this?
I can only find a manual way of doing this using JavaScript by pasting this into the browser URL field
javascript:alert(document.lastModified)
Any ideas greatly received :)
The following will step through an array of URLs and display the last modified date or, if it's not present, the date of the server request.
string[] urls = { "http://boflynn.net", "http://slashdot.org" };
foreach ( string url in urls )
{
System.Net.HttpWebRequest req =
(System.Net.HttpWebRequest) System.Net.WebRequest.Create(url);
System.Net.HttpWebResponse resp =
(System.Net.HttpWebResponse) req.GetResponse();
Console.WriteLine("{0} - {1}", url, resp.LastModified);
}
If you use urllib2 (or perhaps httplib might be better still) in a python script you can inspect the headers that are returned for the last-modified field.
It depends on what you mean by "last updated". Sure, there is the Last-Modified HTTP header, but it can be very misleading. For example, if the page is being served up dynamically, there is a good change that this field will be the current time, even if the content of the page itself (the part useful to humans) has not been updated in a rather long time. This page itself is a good example of this phenomenon.
If you are truly interested in the last time the content was updated, then I don't have an immediate answer.

"name" web pdf for better default save filename in Acrobat?

My app generates PDFs for user consumption. The "Content-Disposition" http header is set as mentioned here. This is set to "inline; filename=foo.pdf", which should be enough for Acrobat to give "foo.pdf" as the filename when saving the pdf.
However, upon clicking the "Save" button in the browser-embedded Acrobat, the default name to save is not that filename but instead the URL with slashes changed to underscores. Huge and ugly. Is there a way to affect this default filename in Adobe?
There IS a query string in the URLs, and this is non-negotiable. This may be significant, but adding a "&foo=/title.pdf" to the end of the URL doesn't affect the default filename.
Update 2: I've tried both
content-disposition inline; filename=foo.pdf
Content-Type application/pdf; filename=foo.pdf
and
content-disposition inline; filename=foo.pdf
Content-Type application/pdf; name=foo.pdf
(as verified through Firebug) Sadly, neither worked.
A sample url is
/bar/sessions/958d8a22-0/views/1493881172/export?format=application/pdf&no-attachment=true
which translates to a default Acrobat save as filename of
http___localhost_bar_sessions_958d8a22-0_views_1493881172_export_format=application_pdf&no-attachment=true.pdf
Update 3: Julian Reschke brings actual insight and rigor to this case. Please upvote his answer.
This seems to be broken in FF (https://bugzilla.mozilla.org/show_bug.cgi?id=433613) and IE but work in Opera, Safari, and Chrome. http://greenbytes.de/tech/tc2231/#inlwithasciifilenamepdf
Part of the problem is that the relevant RFC 2183 doesn't really state what to do with a disposition type of "inline" and a filename.
Also, as far as I can tell, the only UA that actually uses the filename for type=inline is Firefox (see test case).
Finally, it's not obvious that the plugin API actually makes that information available (maybe someboy familiar with the API can elaborate).
That being said, I have sent a pointer to this question to an Adobe person; maybe the right people will have a look.
Related: see attempt to clarify Content-Disposition in HTTP in draft-reschke-rfc2183-in-http -- this is early work in progress, feedback appreciated.
Update: I have added a test case, which seems to indicate that the Acrobat reader plugin doesn't use the response headers (in Firefox), although the plugin API provides access to them.
Set the file name in ContentType as well. This should solve the problem.
context.Response.ContentType = "application/pdf; name=" + fileName;
// the usual stuff
context.Response.AddHeader("content-disposition", "inline; filename=" + fileName);
After you set content-disposition header, also add content-length header, then use binarywrite to stream the PDF.
context.Response.AddHeader("Content-Length", fileBytes.Length.ToString());
context.Response.BinaryWrite(fileBytes);
Like you, I tried and tried to get this to work. Finally I gave up on this idea, and just opted for a workaround.
I'm using ASP.NET MVC Framework, so I modified my routes for that controller/action to make sure that the served up PDF file is the last part of the location portion of the URI (before the query string), and pass everything else in the query string.
Eg:
Old URI:
http://server/app/report/showpdf?param1=foo&param2=bar&filename=myreport.pdf
New URI:
http://server/app/report/showpdf/myreport.pdf?param1=foo&param2=bar
The resulting header looks exactly like what you've described (content-type is application/pdf, disposition is inline, filename is uselessly part of the header). Acrobat shows it in the browser window (no save as dialog) and the filename that is auto-populated if a user clicks the Acrobat Save button is the report filename.
A few considerations:
In order for the filenames to look decent, they shouldn't have any escaped characters (ie, no spaces, etc)... which is a bit limiting. My filenames are auto-generated in this case, and before had spaces in them, which were showing up as '%20's in the resulting save dialog filename. I just replaced the spaces with underscores, and that worked out.
This is by no names the best solution, but it does work. It also means that you have to have the filename available to make it part of the original URI, which might mess with your program's workflow. If it's currently being generated or retrieved from a database during the server-side call that generates the PDF, you might need to move the code that generates the filename to javascript as part of a form submission or if it comes from a database make it a quick ajax call to get the filename when building the URL that results in the inlined PDF.
If you're taking the filename from a user input on a form, then that should be validated not to contain escaped characters, which will annoy users.
Hope that helps.
Try placing the file name at the end of the URL, before any other parameters. This worked for me.
http://www.setasign.de/support/tips-and-tricks/filename-in-browser-plugin/
In ASP.NET 2.0 change the URL from
http://www. server.com/DocServe.aspx?DocId=XXXXXXX
to
http://www. server.com/DocServe.aspx/MySaveAsFileName?DocId=XXXXXXX
This works for Acrobat 8 and the default SaveAs filename is now MySaveAsFileName.pdf.
However, you have to restrict the allowed characters in MySaveAsFileName (no periods, etc.).
Apache's mod_rewrite can solve this.
I have a web service with an endpoint at /foo/getDoc.service. Of course Acrobat will save files as getDoc.pdf. I added the following lines in apache.conf:
LoadModule RewriteModule modules/mod_rewrite.so
RewriteEngine on
RewriteRule ^/foo/getDoc/(.*)$ /foo/getDoc.service [P,NE]
Now when I request /foo/getDoc/filename.pdf?bar&qux, it gets internally rewritten to /foo/getDoc.service?bar&qux, so I'm hitting the correct endpoint of the web service, but Acrobat thinks it will save my file as filename.pdf.
If you use asp.net, you can control pdf filename through page (url) file name.
As other users wrote, Acrobat is a bit s... when it choose the pdf file name when you press "save" button: it takes the page name, removes the extension and add ".pdf".
So /foo/bar/GetMyPdf.aspx gives GetMyPdf.pdf.
The only solution I found is to manage "dynamic" page names through an asp.net handler:
create a class that implements IHttpHandler
map an handler in web.config bounded to the class
Mapping1: all pages have a common radix (MyDocument_):
<httpHandlers>
<add verb="*" path="MyDocument_*.ashx" type="ITextMiscWeb.MyDocumentHandler"/>
Mapping2: completely free file name (need a folder in path):
<add verb="*" path="/CustomName/*.ashx" type="ITextMiscWeb.MyDocumentHandler"/>
Some tips here (the pdf is dynamically created using iTextSharp):
http://fhtino.blogspot.com/2006/11/how-to-show-or-download-pdf-file-from.html
Instead of attachment you can try inline:
Response.AddHeader("content-disposition", "inline;filename=MyFile.pdf");
I used inline in a previous web application that generated Crystal Reports output into PDF and sent that in browser to the user.
File download dialog (PDF) with save and open option
Points To Remember:
Return Stream with correct array size from service
Read the byte arrary from stream with correct byte length on the basis of stream length.
set correct contenttype
Here is the code for read stream and open the File download dialog for PDF file
private void DownloadSharePointDocument()
{
Uri uriAddress = new Uri("http://hyddlf5187:900/SharePointDownloadService/FulfillmentDownload.svc/GetDocumentByID/1/drmfree/");
HttpWebRequest req = WebRequest.Create(uriAddress) as HttpWebRequest;
// Get response
using (HttpWebResponse httpWebResponse = req.GetResponse() as HttpWebResponse)
{
Stream stream = httpWebResponse.GetResponseStream();
int byteCount = Convert.ToInt32(httpWebResponse.ContentLength);
byte[] Buffer1 = new byte[byteCount];
using (BinaryReader reader = new BinaryReader(stream))
{
Buffer1 = reader.ReadBytes(byteCount);
}
Response.Clear();
Response.ClearHeaders();
// set the content type to PDF
Response.ContentType = "application/pdf";
Response.AddHeader("Content-Disposition", "attachment;filename=Filename.pdf");
Response.Buffer = true;
Response.BinaryWrite(Buffer1);
Response.Flush();
// Response.End();
}
}
I believe this has already been mentioned in one flavor or another but I'll try and state it in my own words.
Rather than this:
/bar/sessions/958d8a22-0/views/1493881172/export?format=application/pdf&no-attachment=true
I use this:
/bar/sessions/958d8a22-0/views/1493881172/NameThatIWantPDFToBe.pdf?GeneratePDF=1
Rather than having "export" process the request, when a request comes in, I look in the URL for GeneratePDF=1. If found, I run whatever code was running in "export" rather than allowing my system to attempt to search and serve a PDF in the location /bar/sessions/958d8a22-0/views/1493881172/NameThatIWantPDFToBe.pdf. If GeneratePDF is not found in the URL, I simply transmit the file requested. (note that I can't simply redirect to the file requested - or else I'd end up in an endless loop)
You could always have two links. One that opens the document inside the browser, and another to download it (using an incorrect content type). This is what Gmail does.
For anyone still looking at this, I used the solution found here and it worked wonderfully. Thanks Fabrizio!
The way I solved this (with PHP) is as follows:
Suppose your URL is SomeScript.php?id=ID&data=DATA and the file you want to use is TEST.pdf.
Change the URL to SomeScript.php/id/ID/data/DATA/EXT/TEST.pdf.
It's important that the last parameter is the file name you want Adobe to use (the 'EXT' can be about anything). Make sure there are no special chars in the above string, BTW.
Now, at the top of SomeScript.php, add:
$_REQUEST = MakeFriendlyURI( $_SERVER['PHP\_SELF'], $_SERVER['SCRIPT_FILENAME']);
Then add this function to SomeScript.php (or your function library):
function MakeFriendlyURI($URI, $ScriptName) {
/* Need to remove everything up to the script name */
$MyName = '/^.*'.preg_quote(basename($ScriptName)."/", '/').'/';
$Str = preg_replace($MyName,'',$URI);
$RequestArray = array();
/* Breaks down like this
0 1 2 3 4 5
PARAM1/VAL1/PARAM2/VAL2/PARAM3/VAL3
*/
$tmp = explode('/',$Str);
/* Ok so build an associative array with Key->value
This way it can be returned back to $_REQUEST or $_GET
*/
for ($i=0;$i < count($tmp); $i = $i+2){
$RequestArray[$tmp[$i]] = $tmp[$i+1];
}
return $RequestArray;
}//EO MakeFriendlyURI
Now $_REQUEST (or $_GET if you prefer) is accessed like normal $_REQUEST['id'], $_REQUEST['data'], etc.
And Adobe will use your desired file name as the default save as or email info when you send it inline.
I was redirected here because i have the same problem. I also tried Troy Howard's workaround but it is doesn't seem to work.
The approach I did on this one is to NO LONGER use response object to write the file on the fly. Since the PDF is already existing on the server, what i did was to redirect my page pointing to that PDF file. Works great.
http://forums.asp.net/t/143631.aspx
I hope my vague explanation gave you an idea.
Credits to Vivek.
Nginx
location /file.pdf
{
# more_set_headers "Content-Type: application/pdf; name=save_as_file.pdf";
add_header Content-Disposition "inline; filename=save_as_file.pdf";
alias /var/www/file.pdf;
}
Check with
curl -I https://example.com/file.pdf
Firefox 62.0b5 (64-bit): OK.
Chrome 67.0.3396.99 (64-Bit): OK.
IE 11: No comment.
Try this, if your executable is "get.cgi"
http://server,org/get.cgi/filename.pdf?file=filename.pdf
Yes, it's completely insane. There is no file called "filename.pdf" on the server, there is directory at all under the executable get.cgi.
But it seems to work. The server ignores the filename.pdf and the pdf reader ignores the "get.cgi"
Dan

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