Hi I'm downloading a file to an app on iOS using the function readfile() on a PHP web service and I want to know if the file is downloaded correctly but I don't know how I can do that.
So what I'm trying is to do some echo to know if the file has been downloaded like this:
echo "before";
readfile($file);
echo "after";
But the response I get is this:
beforePK¿¿¿
Any one knows what does this mean or how can I know if the file is downloaded correctly?
UPDATE:
Yes it's a zip file, here are my headers
header("Cache-Control: public");
header("Content-Description: File Transfer");
header("Content-Disposition: attachment; filename=$ticket");
header("Content-Type: application/zip");
header("Content-Transfer-Encoding: binary");
You're trying to output the contents of a zip file aren't you?
readfile($file) works the same as echo file_get_contents($file). If you're trying to present someone a file to download, do not add any additional output else you risk breaking the file.
I would also recommend reading up on the header function. That way you can explicitly tell the browser that you're sending a file, not an HTML page that has file-like contents. (See the examples involving Content-Type)
PHP should be setting the correct headers prior to readfile() - this LITERALLY reads the file out to the browser/app... but the browser/app needs to know what to do with it...
Usually you just assume that once the connection has closed that the data is done being transferred. If you want to validate that the file has been transferred fully, and without corruption you'll need to use a data structure like XML or JSON which will:
Delimit the data fields and cause the XML/JSON parser to throw an error if one is omitted, aka the transfer was cut off before it finished.
Allow you to embed more than one piece of data with the response, eg. an MD5 hash of the file that can be re-calculated client-side to verify that the data is intact.
eg:
$file = 'myfile.zip';
$my_data = array(
'file' => base64_encode(file_get_contents($file)),
'hash' => md5_file($file)
)
//header calls
header(...)
echo json_encode($my_data);
exit;
Related
I need to get a remote file and give it to user without saving it to my server disk (for hiding original URL) and found a lot of posts about download external files with various functions like file_get_contents or readfile. Already I'm using this one:
function startDownload($url){
if($this->url_exists($url))
{
//get filename from url
$name=$this->getFileName($url);
//first flush clear almost output
ob_end_flush();
//final clear
ob_clean();
//set headers
header('Content-Type: application/octet-stream');
header("Content-Transfer-Encoding: Binary");
header("Content-disposition: attachment; filename=\"" . $name . "\"");
//send file to client;
readfile($url);
//exit command is important
exit;
}
else JFactory::getApplication()->enqueueMessage(JText::_('URL_NOT_FOUND'), 'error');
}
And that's working but there is a problem! For a file with 200 MB size it takes ~ 10 seconds to start download in client browser. I think it's because readfile first downloads whole file to my server buffer and then give it to user. Is that right?
And is it possible to make it faster? for example download be started before fetch ended or it isn't possible technically?
In fact I don't know that this method is optimised or not. Any technical advice would be appreciated.
Note :
I know that this function should be changed for big files and that's not my concern now.
I consider to buy the external server in the same datacenter to make this download faster.
Target is that [File server] be separate than the file [online shop].
I tested curl method that mentioned by #LawrenceCherone. It worked nicely but when moved it to my project the result was the same as readfile (white screen for a few seconds).
So suspect to readfile() function. Separate my previous code to a single PHP file and result was amazing! Download starts immediately.
So I think my guess wasn't right and problem was not related to readfile function.
After a little search found a minor modification. I added below line :
while (ob_get_level()) ob_end_clean();
before the :
readfile($url);
And now download starts before whole file fetched in my server.
We are trying to create a webpage in laravel where people are going to be able upload their codefiles to our server, so that other users can watch the code and download it in codefiles if they like it. We however can't figure out the best way to make this happen.
I tried to just let php get a file and echo out the content. this worked well fot html and css, but with php nothing got displayed what so ever. someone mentioned using eval(), however i've read that it is a really bad idea to do so. Another idea would be to stash the code in a database and fetch it from there, which we have tried before, but it sort of over complicated, and avoiding to do so would be prefereable, and instead go directly to i file.
So my question is, do anybody have an idea that might work safely, both for us and our server and for the users.
Something like this:
<?php
// read Codefile
$TheCode = file_get_contents($codefile);
// Print it...
echo htmlentities($TheCode);
?>
Save the php code in a flat file like one with a .dat extension.
then read the file.
$toechp = file(static.dat);
echo $toecho;
You can allow .dat files to be downloaded on browser using headers.
<?php
$file = "http://example.com/static.dat";
header("Content-Description: File Transfer");
header("Content-Type: application/octet-stream");
header("Content-Disposition: attachment; filename=\"$file\"");
readfile ($file);
?>
and you are done.
I have a simple form that, when posted back, calls a function to initiate a download. The path and file name are pulled from the database then I'm using headers to start the download. My code for the download is:
//START DOWNLOAD
header('Content-type: "application/octet-stream"');
header('Content-Disposition: attachment; filename="'.$FILE_PATH.$FILE_NAME.'"');
header("Content-Transfer-Encoding: binary");
header("Connection: close")
In the example above, the $FILE_PATH variable is /downloads/software/ and the $FILE_NAME variable is client-installer.exe. So, what I would expect is a file called client-installer.exe (approximately 70MB) to be downloaded to the client. Instead, I get a file called _downloads_software_client-installer.exe and approximately 10KB.
I thought maybe I needed to urlencode the file path/name but that didn't fix the issue either. So I'm left thinking perhaps I have something wrong with the header but can't seem to find it.
Thank you!
The filename header just denotes what the file should be called. It must contain only a filename, not a path. The internal path on the server's hard disk is irrelevant and of no interest to the client. Your server will have to output the actual file data in the response, the client can't take it from the server given the path.
See readfile.
What i am trying to do is provide a way for an Xls file generated on the client side in js to be downloaded. So I have the xls in a string in js and need to give the user a way to download it and open it in excel.
As i understand the only way to do this is to do it on the server via the content type, so I have tried to provide a php that does a file relay... Here is the php
<?php
header("Content-type: application/octet-stream");
header("Content-Disposition: attachment; filename=\"my-data.csv\"");
$data=stripcslashes($_REQUEST['csv_text']);
echo $data;
?>
A request can end up being rather long so for example i might have this request... (actually shortened greatly).
I am not good with php, can anyone suggest a better way to modify this relay script (or better way entirely) to accomplish this?
http://myserver.com/ExcelRelay.php?csv_text=Id%09City%09Phone%09Address%201%09Address%202%09State%09Type%09Employees%09Revenue%09Leed%09Established%09Comments%09Country%09Postal%20Code%09Territory%0A3%09Greensboro%096538227668%09%0978%20Rocky%20Second%20St.%09New%20Jersey%09Remote%09%090%091%09Sun%20Aug%2009%201964%2000%3A00%3A00%20GMT-0400%20%28Eastern%20Daylight%20Time%29%09%22Et%20quad%20estis%20vobis%20homo%2C%20si%20nomen%20transit.%20%0A%20Sed%20quad%20estis%20vobis%20homo%2C%20si%20quad%20ut%20novum%20vobis
Thanks For the Response, The final script was
<?php header("Content-type: application/octet-stream");
header("Content-Disposition: attachment;filename=\"".$_POST['filename']."\"");
echo $_POST['data'];
?>
One word: POST.
Request Url Too Long is a client side error, and one that is (AFAIK) exclusive to IE, these days. If you want to send the data to the server and have it sent back to you as a file, you will have to send the data in the body of the request.
See here for more information.
I want to write a text file in the server through Php, and have the client to download that file.
How would i do that?
Essentially the client should be able to download the file from the server.
This is the best way to do it, supposing you don't want the user to see the real URL of the file.
<?php
$filename="download.txt";
header("Content-disposition: attachment;filename=$filename");
readfile($filename);
?>
Additionally, you could protect your files with mod_access.
In addition to the data already posted, there is a header you might want to try.
Its only a suggestion to how its meant to be handled, and the user agent can chose to ignore it, and simply display the file in the window if it knows how:
<?php
header('Content-Type: text/plain'); # its a text file
header('Content-Disposition: attachment'); # hit to trigger external mechanisms instead of inbuilt
See Rfc2183 for more on the Content-Disposition header.
PHP has a number of very simplistic, C-like functions for writing to files. Here is an easy example:
<?php
// first parameter is the filename
//second parameter is the modifier: r=read, w=write, a=append
$handle = fopen("logs/thisFile.txt", "w");
$myContent = "This is my awesome string!";
// actually write the file contents
fwrite($handle, $myContent);
// close the file pointer
fclose($handle);
?>
It's a very basic example, but you can find more references to this sort of operation here:
PHP fopen
If you set the content type to application/octet-stream, the browser will ALWAYS offer file as a download, and will never attempt to display it internally, no matter what type of file it is.
<?php
filename="download.txt";
header("Content-type: application/octet-stream");
header("Content-disposition: attachment;filename=$filename");
// output file content here
?>
Just post a link on the site to http://example.com/textfile.php
And in that PHP file you put the following code:
<?php
header('Content-Type: text/plain');
print "The output text";
?>
That way you can create the content dynamic (from a database)...
Try to Google to oter "Content-Type" if this one is not the one you are looking for.