I'm facing a big issue IMO.
First, here's my code:
.bind('uploadSuccess', function(event, file, serverData){
if(serverData === 'nofile') {
var swfu = $.swfupload.getInstance('#form');
swfu.cancelUpload(file.id); // This part is not working :(
} else {
alert('File uploaded');
}
})
In this part I'm checking server response (I'm have strict validation restrictions). Now my question. Is it possible to remove uploaded file from queue? Basically, if server returns error I display error message, but... this file still exsit in the queue (I've implemented checking filename and filesize to avoid duplicated uploads) and user is not possible to replace this file (due to upload and queue limit).
I was trying to search for a solution, but without success. Any ideas?
Regards,
Tom
From the link
http://swfupload.org/forum/generaldiscussion/881
"The cancelUpload(file_id) function
allows you to cancel any file you have
queued.
You just have to keep the file's ID
value so you can pass it to
cancelUpload when you call it."
Probably you have to keep the file ID before sending anything to the server
Related
I'm trying to use Casablanca to consume a REST api.
I've been following the microsoft tutorial, how ever i'm getting a crash and I cannot figure it out.
I'm using visual studio 2017 with C++11
I've codded a function GetRequest() that do work when used in a new empty project, but when I try to use it on my Project (Very big project with millions of code lines).
I'm crashing in the constructor of http_client, in the file xmemory0 line 118.
const uintptr_t _Ptr_container = _Ptr_user[-1];
This is a link to the callstack : https://i.imgur.com/lBm0Hv7.png
void RestManager::GetRequest()
{
auto fileStream = std::make_shared<ostream>();
// Open stream to output file.
pplx::task<void> requestTask = fstream::open_ostream(U("results.html")).then([=](ostream outFile)
{
*fileStream = outFile;
// Create http_client to send the request.
http_client client(U("XXX/XXX.svc/"));
// Build request URI and start the request.
uri_builder builder(U("/IsLive"));
builder.append_query(U("q"), U("cpprestsdk github"));
return client.request(methods::GET, builder.to_string());
})
// Handle response headers arriving.
.then([=](http_response response)
{
printf("Received response status code:%u\n", response.status_code());
// Write response body into the file.
return response.body().read_to_end(fileStream->streambuf());
})
// Close the file stream.
.then([=](size_t)
{
return fileStream->close();
});
// Wait for all the outstanding I/O to complete and handle any exceptions
try
{
requestTask.wait();
}
catch (const std::exception &e)
{
printf("Error exception:%s\n", e.what());
}
}
EDIT : I just want to add that the http_client constructor is the issue. It always crash inside it no matter what I send as parameter.
The wierd thing is that it's not crashing when i just make a main() that call this function.
I guess it must be due to some memory issues, however I have no idea how could I debug that.
Does anyone would have an idea about it?
Thanks and have a great day!
I've experienced a similar issue on ubuntu. It works in an empty project, but crashes randomly when put into an existing large project, complaining memory corruptions.
Turns out that the existing project loaded a proprietary library, which is using cpprestsdk (casablanca) internally. Even cpprestsdk is static linked, its symbols are still exported as Weak Symbols. So either my code crashes, or the proprietary library crashes.
Ideally, my project can be divided into several libraries, and load them with RTLD_LOCAL to avoid symbol clashes. But the proprietary library in my project only accept RTLD_GLOBAL, otherwise it crashes... So the import order and flags become important:
dlopen("my-lib-uses-cpprest", RTLD_LOCAL); //To avoid polluting the global
dlopen("proprietary-lib-with-built-in-cpprest", RTLD_GLOBAL); //In my case, this lib must be global
dlopen("another-lib-uses-cpprest", RTLD_DEEPBIND); //To avoid being affected by global
"it will probably never concern anyone."
I agree with that.
I guess this issues was very specific, and it will probably never concern anyone, but still I'm going to update on everything I found out about it.
On this project, we are using custom allocator, if i'm not wrong, it's not possible to give our custom allocator to this lib, which result to many random crash.
A good option to fix it would be to use the static version to this lib, however, since we are using a lot of dynamic lib, this option wasn't possible for us.
If you are on my case, I would advice to use the libcurl and rapidjson, it's a bit harder to use, but you can achieve the same goal.
I have developed a C# application, in the application the users choose a photo for each record. However the user should also be able to change the pre-selected photo with a newer one. When the user changes the photo the application first deletes the old photo from the application directory then copies the new photo, but when it does that the application gives an exception because the file is used by the application so it cannot be deleted while the application is running. Does any one have a clue how to sort this out? I appreciate your help
This is the exception
The process cannot access the file
'D:\My
Projects\Hawkar'sProject\Software\Application\bin\Debug\Photos\John
Smith.png' because it is being used by
another process.
//defining a string where contains the file source path
string fileSource = Open.FileName;
//defining a string where it contains the file name
string fileName = personNameTextBox.Text + ".png" ;
//defining a string which specifies the directory of the destination file
string fileDest = dir + #"\Photos\" + fileName;
if (File.Exists(fileDest))
{
File.Delete(fileDest);
//this is a picturebox for showing the images
pbxPersonal.Image = Image.FromFile(dir + #"\Photos\" + "No Image.gif");
File.Copy(fileSource, fileDest);
}
else
{
File.Copy(fileSource, fileDest);
}
imageIDTextBox.Text = fileDest;
First of all, you code is not good.
The new image is only copied if there is currently no image (else).
But if there is an old image, you only delete this image, but never copy the newer one (if).
The code should better look like this:
if (File.Exists(fileDest))
{
File.Delete(fileDest);
}
File.Copy(fileSource, fileDest);
imageIDTextBox.Text = fileDest;
This code should work, but if you are getting an exception that the file is already in use, you should check "where" you use the file. Perhaps you are reading the file at program start. Check all parts of your program you are accessing these user files if there are some handles open.
Thanks a lot for your help and sorry for the mistake in the code I just saw it, my original code is just like as you have written but I don't know maybe when I posted accidentally I've put like this. when the application runs there is a picturebox which the image of each record is shown, that is why the application is giving an exception when I want to change the picture because it has been used once by the picturebox , however I've also tried to load another picture to the picture box before deleting the original one but still the same. I've modified the above could if you want to examine it
I want to get file size I'm doing this:
my $filename=$query->param("upload_file");
my $filesize = (-s $filename);
print "Size: $filesize ";`
Yet it is not working. Note that I did not upload the file. I want to check its size before uploading it. So to limit it to max of 1 MB.
You can't know the size of something before uploading. But you can check the Content-Length request header sent by the browser, if there is one. Then, you can decide whether or not you want to believe it. Note that the Content-Length will be the length of the entire request stream, including other form fields, and not just the file upload itself. But it's sufficient to get you a ballpark figure for conformant clients.
Since you seem to be running under plain CGI, you should be able to get the request body length in $ENV{CONTENT_LENGTH}.
Also want to sanity check against possibly already having post max set (from perldoc CGI):
$CGI::POST_MAX
If set to a non-negative integer, this variable puts a ceiling on the size of
POSTings, in bytes. If CGI.pm detects a POST that is greater than the ceiling,
it will immediately exit with an error message. This value will affect both
ordinary POSTs and multipart POSTs, meaning that it limits the maximum size of
file uploads as well. You should set this to a reasonably high value, such as
1 megabyte.
The uploaded file is stashed in a tmp location on the server when the form is submitted, check the file size there.
Supply the value for $field.
my $upload_filehandle = $query->upload($field);
my $tmpfilename = $query->tmpFileName($upload_filehandle);
my $file_size = (-s $tmpfilename);
This has nothing to do with Perl.
You are trying to read the filesize of a file on the user's computer using commands that read files on your server, what you want can't be done using Perl.
This is something that has to be done in the browser, and looking briefly at these questions it's either very hard or impossible.
Your best bet is to allow the user to start the upload and abort if the file is too big.
If you want to check before you process the request, you might be better off checking on the web page that triggers the request. I don't think the web browser can do it on it's own, but if you don't mind Flash, there are many Flash upload tools that can check things like size (as well as file types) and prevent uploading.
A good one to start with is the YUI Uploader. Lots more here: What is the best multiple file JavaScript / Flash file uploader?
Obviously you would want to check on the server side too, but by the time the user has started sending the request to the server, you are already using up your CPU cycles and bandwidth.
Thanks everyone for your replies; I just found out why $filesize = (-s $filename); was not working before, it is due that I was checking file size while sending Ajax request and not while re submitting the page.That's why I was having size to be zero. I fixed that to submit the page and it worked. Thanks.
Just read this post but while checking the content-length is a good approximate pre-check you could also save the file to temporary folder and then perform any kind of check on it. If it doesn't meet your criteria just delete and don't send it to it's final destination.
Look at the perl documentation for file stats -X - perldoc.perl.org and stat-perldoc.perl.org. Also, you can look at this upload script which is doing the similar thing what you are trying to do.
How would I validate that a jpg file is a valid image file. We are having files written to a directory using FTP, but we seem to be picking up the file before it has finished writing it, creating invalid images. I need to be able to identify when it is no longer being written to. Any ideas?
Easiest way might just be to write the file to a temporary directory and then move it to the real directory after the write is finished.
Or you could check here.
JPEG::Error
[arguments: none] If the file reference remains undefined after a call to new, the file is to be considered not parseable by this module, and one should issue some error message and go to another file. An error message explaining the reason of the failure can be retrieved with the Error method:
EDIT:
Image::TestJPG might be even better.
You're solving the wrong problem, I think.
What you should be doing is figuring out how to tell when whatever FTPd you're using is done writing the file - that way when you come to have the same problem for (say) GIFs, DOCs or MPEGs, you don't have to fix it again.
Precisely how you do that depends rather crucially on what FTPd on what OS you're running. Some do, I believe, have hooks you can set to trigger when an upload's done.
If you can run your own FTPd, Net::FTPServer or POE::Component::Server::FTP are customizable to do the right thing.
In the absence of that:
1) try tailing the logs with a Perl script that looks for 'upload complete' messages
2) use something like lsof or fuser to check whether anything is locking a file before you try and copy it.
Again looking at the FTP issue rather than the JPG issue.
I check the timestamp on the file to make sure it hasn't been modified in the last X (5) mins - that way I can be reasonably sure they've finished uploading
# time in seconds that the file was last modified
my $last_modified = (stat("$path/$file"))[9];
# get the time in secs since epoch (ie 1970)
my $epoch_time = time();
# ensure file's not been modified during the last 5 mins, ie still uploading
unless ( $last_modified >= ($epoch_time - 300)) {
# move / edit or what ever
}
I had something similar come up once, more or less what I did was:
var oldImageSize = 0;
var currentImageSize;
while((currentImageSize = checkImageSize(imageFile)) != oldImageSize){
oldImageSize = currentImageSize;
sleep 10;
}
processImage(imageFile);
Have the FTP process set the readonly flag, then only work with files that have the readonly flag set.
I am trying to register to a "Device added/ Device removed" event using WMI. When I say device - I mean something in the lines of a Disk-On-Key or any other device that has files on it which I can access...
I am registering to the event, and the event is raised, but the EventType propery is different from the one I am expecting to see.
The documentation (MSDN) states : 1- config change, 2- Device added, 3-Device removed 4- Docking. For some reason I always get a value of 1.
Any ideas ?
Here's sample code :
public class WMIReceiveEvent
{
public WMIReceiveEvent()
{
try
{
WqlEventQuery query = new WqlEventQuery(
"SELECT * FROM Win32_DeviceChangeEvent");
ManagementEventWatcher watcher = new ManagementEventWatcher(query);
Console.WriteLine("Waiting for an event...");
watcher.EventArrived +=
new EventArrivedEventHandler(
HandleEvent);
// Start listening for events
watcher.Start();
// Do something while waiting for events
System.Threading.Thread.Sleep(10000);
// Stop listening for events
watcher.Stop();
return;
}
catch(ManagementException err)
{
MessageBox.Show("An error occurred while trying to receive an event: " + err.Message);
}
}
private void HandleEvent(object sender,
EventArrivedEventArgs e)
{
Console.WriteLine(e.NewEvent.GetPropertyValue["EventType"]);
}
public static void Main()
{
WMIReceiveEvent receiveEvent = new WMIReceiveEvent();
return;
}
}
Well, I couldn't find the code. Tried on my old RAC account, nothing. Nothing in my old backups. Go figure. But I tried to work out how I did it, and I think this is the correct sequence (I based a lot of it on this article):
Get all drive letters and cache
them.
Wait for the WM_DEVICECHANGE
message, and start a timer with a
timeout of 1 second (this is done to
avoid a lot of spurious
WM_DEVICECHANGE messages that start
as start as soon as you insert the
USB key/other device and only end
when the drive is "settled").
Compare the drive letters with the
old cache and detect the new ones.
Get device information for those.
I know there are other methods, but that proved to be the only one that would work consistently in different versions of windows, and we needed that as my client used the ActiveX control on a webpage that uploaded images from any kind of device you inserted (I think they produced some kind of printing kiosk).
Oh! Yup, I've been through that, but using the raw Windows API calls some time ago, while developing an ActiveX control that detected the insertion of any kind of media. I'll try to unearth the code from my backups and see if I can tell you how I solved it. I'll subscribe to the RSS just in case somebody gets there first.
Well,
u can try win32_logical disk class and bind it to the __Instancecreationevent.
You can easily get the required info
I tried this on my system and I eventually get the right code. It just takes a while. I get a dozen or so events, and one of them is the device connect code.