By default, attachments are viewed reliably using https://docs.google.com/gview , but it turns out that you are allowed to request files via simple HTTP. This makes it a little easier to determine what is happening using Wireshark .
As you pointed out, it was already clear that PDF is converted on the server side to PNG ( ImageMagick is really a smart solution for this purpose), the obvious reason for this is to preserve the exact layout while maintaining the ability to view the file without having to view the PDF files.
, , , PDF XML /gview? a = gt & docid = & chan = & thid = ( ). Wireshark XML, Firefox Live HTTP Headers. :
<pdf2xml>
<meta name="Author" content="Bruce van der Kooij"/>
<meta name="Creator" content="Writer"/>
<meta name="Producer" content="OpenOffice.org 3.0"/>
<meta name="CreationDate" content="20090218171300+01'00'"/>
<page t="0" l="0" w="595" h="842">
<text l="188" t="99" w="213" h="27" p="188,213">Programmabureau</text>
<text l="85" t="127" w="425" h="27" p="85,117,209,61,277,21,305,124,436,75">Nederland Open in Verbinding (NOiV)</text>
</page>
</pdf2xml>
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, (GPL), pdf2xml, , . :
<?xml version="1.0" encoding="utf-8" ?>
<pdf2xml pages="3">
<title>My Title</title>
<page width="780" height="1152">
<font size="10" face="MHCJMH+FuturaT-Bold" color="#FF0000">
<text x="324" y="37" width="132" height="10">Friday, September 27, 2002</text>
<img x="324" y="232" width="277" height="340" src="text_pic0001.png"/>
<link x="324" y="232" width="277" height="340" dest_page="2" dest_x="141" dest_y="187"/>
</font>
<font size="12" face="AGaramond-Regular" italic="true" bold="true">
<text x="509" y="68" width="121" height="12">This is a test PDF file</text>
<link x="509" y="68" width="121" height="12" href="www.mobipocket.com"/>
</font>
</page>
</pdf2xml>
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