PHP Download not working with path coming from DB - php

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.

Related

Readfile is best solution to download external files?

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.

PDF Download gives corrupt PDF php

I am saving a pdf file, and then attempting to download it using php.
The script seemed to work fine, but all of the sudden not anymore.
Can anybody see what I am missing?
PS: the file I am downloading is only 4.3kb big, so I assume that would be because it is not downloading at all. The actual file size should be bigger than this.
$pdf->output(ROOTDIR.'/modules/addons/statement_generator/reports/statement.pdf');
if($action=='print'){
$file_name = 'statement.pdf';
$file_url = "http://".$_SERVER['SERVER_NAME']."/modules/addons/statement_generator/reports/" . $file_name;
header('Content-Type: application/pdf');
header("Content-Transfer-Encoding: Binary");
header("Content-disposition: attachment; filename=\"".$file_name."\"");
readfile($file_url);
exit;
}
The $pdf->output() call will already send the PDF to the client. The file will not be saved to your local folder (Didn't you checked at least this?) because you have to pass "F" as the snd parameter.
After that you try to read from an URL (!!!!) that does not exists and which maybe return a nicely styled 404 html response. Two issues here:
Why are you using http when you have the local path used some lines above? Use the local path only!
The content returned by the URL is append to the already send PDF which ends in a document mixed of PDF and HTML (the 404 response) -> corrupted PDF
Conclusion: Use "F" as the 2nd parameter and use the same path for both writing and reading and not a mix of local path and URL.

How to download a file without an extension in PHP

I have a file with no extension on it, but I know it's a tiff. I want to be able to download this file via PHP.
I created a page with a link to another php page, which has the following content:
<?php
$imgPath = 'http://server/23700-b074137f-eb5c-45d6-87c2-13c96812345b';
header("Content-disposition: attachment; filename=invoice.tiff");
header("Content-type: image/tiff");
readfile($imgPath);
?>
When I click the link, I get a prompt to download invoice.tiff, but it's 0 bytes.
However, if I rename the file on the server to 23700-b074137f-eb5c-45d6-87c2-13c96812345b.tiff (and change the $imgPath), it works.
How do I accomplish this without renaming the file to include the extension?
It's possible the 'tiff' extension is registered as a known file type on the server, so when you rename and request the tiff it's permissions will allow you to open it. However, with no extension, the security is probably stopping you from reading it, as mentioned by 'Mike B' above. To check this try just entering the file name in your browser address bar and see if it opens, both with and without the 'tiff' extension. There is no workaround for getting past the security issue, short of changing the severs security which would be very bad.
You are retrieving the file from a URL, therefore activating the 'fopen wrappers' in readfile. In general, you should not do this, especially when working locally since it invokes a lot of unnecessary overhead and (in this case) unwanted 'magic' behaviour.
Just use readfile on the local path to the file, and it'll be fine, or use die(file_get_contents($imgPath)) instead of the last line to circumvent PHP's native behaviour.
It works for me:
$imgPath = 'http://server/23700-b074137f-eb5c-45d6-87c2-13c96812345b';
$f = fopen($imgPath, "r");
header("Content-disposition: attachment; filename=invoice.tiff");
header("Content-type: image/tiff");
fpassthru($f);
You should also add the content-length header like so:
// untested code
header('Content-Length: '.strlen(stream_get_contents($imgPath)));

Link to a PDF in html, the file has no extension, but I know it is pdf how to make it open appropriately

First post. I'm working on a project for a client where they have pdf files uploaded to a file structure (LAMP Stack) but the files have no extensions on them. Under the assumption that those files have to be PDF how would I get the browsers to understand that, and open them accordingly? Obviously with adding the file extensions this would suddenly work but I can't change the way their system works, it would result in too many changes and they are on a tight deadline. As for saving a temporary copy somewhere, I could do that, but I was hoping for a better solution. Is there a way to suggest to the browsers that they open a file a certain way?
Any thoughts guys/gals?
You just set the application type and file name in the headers, like so:
// This points to the file in question, note that it doesn't
// care whether it has an extension on the name or not.
$filePathOnDisk = '/path/to/your/pdffile';
// You can make this whatever you like, it doesn't have to
// be the same as the file name on the disk! This is the name of the file your end
// user will see when they are asked if they want to save. open, etc in the browser.
$fileName = 'file.pdf';
$data = file_get_contents($filePathOnDisk);
header("Content-type: application/pdf");
header("Content-disposition: attachment;filename=$fileName");
echo $data;
See PHP: stream remote pdf to client browser and Proper MIME media type for PDF files for reference as well.
Tested
You can use the following which will prompt the user to save the (PDF) file on their computer.
Notice the different file names.
One is the file that will be uploaded/prompted to the user download_example.pdf, while the other is the file without an extension as set in readfile('example');
<?php
header('Content-type: application/pdf');
header('Content-Disposition: attachment; filename="download_example.pdf"');
readfile('example');
?>

What does the "PK¿¿¿" response means in PHP

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;

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