Dowload Links Get Called 2x Via Android:Chrom

[fivestringsurf]

I have a php application that serves pdf downloads.  It works fine on all devices and browsers with one small but really annoying side-effect (edge-case for sure)

When I look at my download logs anytime the download is triggered from Chrome on Android it is called twice!  Bizarre behavior and I can't figure it out.

 

Some background:

 

The download is a pdf that get's created on the fly.

All requests get processed through my index.php controller.

 

I was serving the request with javascript via:

window.open('export?file=something_to_inform_the_controller');

Works great in all browsers and devices but android chrome triggers this twice.

 

So I got wise and though maybe a direct link would work better:

<a target="_blank" href="http://mysite.com/export?file=abc123" download="file.pdf">DL link</a>
or
<a target="_blank" href="http://mysite.com/export?file=abc123">DL link</a>
or
<a target="_self" href="http://mysite.com/export?file=abc123" download="file.pdf">DL link</a>
or
<a target="_self" href="http://mysite.com/export?file=abc123">DL link</a>

Nope, none of these flavors prevents android/chrome from double downloading.

 

Then I researched my php header settings and tried:

content-disposition: inline  vs.

content-disposition: attachment    with no success

 

Note, the download is logged when the controller processes the request for the download.  I have duplicated download events for all downloads on android/chrome.  It's strange that I have not found a solution online for this or maybe I'm overlooking something silly.

 

Any ideas?

[kicken]

It's because the browser initially requests the URL. Once it determines that it's content it can't handle and needs to be downloaded it passes the URL off to a separate download manager application which will then re-request the url and complete the download in the background.

 

This behavior is by design, there isn't anything you can do to make it issue only a single request.

[fivestringsurf]

@kicken,

 

excellent answer.  The reason I was most annoyed by this was when a user looks at their download history if they have been using an android device everything is doubled! 
I guest the solution is:

a) screw you android users (you're log activity is doubled for download requests)

b) don't log requests made by same user/link within <3 seconds of one another

 

Thanks again for your answer.