PMK Forced Download

h1. PMK Forced Download

Force a download on links to files. With this extension it's possible to force download of files like images, PDFs, MP3 ect., overriding the browser settings.

(Normally when you click on a TYPO3 link to a file like an image, the image will open in the browser.) 

Works by extending the *stdWrap/typolink* function. So the extension can be used in other extensions which uses the standard TYPO3 typolink functionality when linking.

h2. Usage

h3. Example of usage as extended stdWrap parameter (Requires TYPO3 v4.2+):

<pre>

10 = TEXT

10.value = download

10.typolink.parameter = fileadmin/templates/images/dwarf_male120x.gif

10.typolink.parameter.makeDownloadLink = 1

</pre>

h3. Example of usage as userFunction:

<pre>

10 = TEXT

10.value = download

10.typolink.parameter = fileadmin/templates/images/dwarf_male120x.gif

10.typolink.parameter.postUserFunc = tx_pmkfdl->makeDownloadLink

</pre>

If the typolink points to a valid file, then the link will be modified to something like this:

<pre>

http://www.mydomain.com/index.php?eID=pmkfdl&file=fileadmin%2Ftemplates%2Fimages%2Fdwarf_male120x.gif&ck=a94fad5a0262b2e00e1aa72e8aac4c30

</pre>

This link will open up a requester in the browser, asking the user what he wants to do with the file (Save, Open etc.)

A MD5 checksum is added as a 2nd parameter to insure that it is the correct file that is being downloaded.

(If the MD5 checksum doesn't match the file, then the download will be terminated.)

h2. Forced download

If you want to force a download, without opening up the browser requester, you can add a special option/parameter called "forcedl"

h3. Example of usage as extended stdWrap parameter, with "forcedl" set (Requires TYPO3 v4.2+):

<pre>

10 = TEXT

10.value = download

10.typolink.parameter = fileadmin/templates/images/dwarf_male120x.gif

10.typolink.parameter.makeDownloadLink = forcedl

</pre>

h3. Example of usage as userFunction, with "forcedl" set:

<pre>

10 = TEXT

10.value = download

10.typolink.parameter = fileadmin/templates/images/dwarf_male120x.gif

10.typolink.parameter.postUserFunc = tx_pmkfdl->makeDownloadLink

10.typolink.parameter.postUserFunc.makeDownloadLink = forcedl

</pre>

h2. Special "register" values.

After creating a download link, 2 special register values are available:

* filesize - This contains the size of the file. (in bytes) 

* filetype - This contains the type of the file. (gif, pdf, zip etc.)

h3. Example of using the register value:

<pre>

10 = COA

10 {

	# Display the filelink

	10 = TEXT

	10.value = download

	10.typolink.parameter = fileadmin/templates/images/dwarf_male120x.gif

	10.typolink.parameter.postUserFunc = tx_pmkfdl->makeDownloadLink

	10.typolink.parameter.postUserFunc.makeDownloadLink = forcedl

	# Display the filesize from register value

	20 = TEXT

	20.data = register:filesize

	20.bytes = 1

	20.wrap = <div>Filesize:&nbsp;|</div>

	# Display the filetype from register value

	30 = TEXT

	30.data = register:filetype

	30.wrap = <div>Filetype:&nbsp;|</div>

}

</pre>

h3. Advanced example of using the register value for displaying a filetype icon:

<pre>

10 = COA

10 {

	wrap = <div>|</div>

	# First we store the link in a register value, since

	# we want to display an icon BEFORE the link.

	10 = LOAD_REGISTER

	10.filelink.cObject = TEXT

	10.filelink.cObject {

		value = download stdWrap

		typolink.parameter = fileadmin/templates/images/dwarf_male120x.gif

		typolink.parameter.makeDownloadLink = 1

	}

	# Display the fileicon and filelink

	20 = CASE

	20 {

		# Wrapping of image, incl. the filelink from previously created register value

		stdWrap.dataWrap = | {register:filelink}

		# Case key is the filetype (from register value)

		key.data = register:filetype

		default = IMAGE

		default.file = fileadmin/fileicons/default.gif

		gif < .default

		gif.file = fileadmin/fileicons/gif.gif

		# You can add more types here

	}

	# Display the filesize ( from register value)

	30 = TEXT

	30.data = register:filesize

	30.bytes = 1

	30.wrap =  (|)

}

</pre>

h2. Enabling the functionality for links created in the RTE.

Since the extension works on standard typolink generated links, it's quite easy to implement it for RTE generated links too. Just add the following line to your Typoscript Setup:

<pre>

lib.parseFunc_RTE.tags.link.typolink.parameter.postUserFunc = tx_pmkfdl->makeDownloadLink

</pre>

h2. Known Problems

Due to a (still unfixed) bug in interface.tslib_content_stdwraphook.php (See Bugtracker http://bugs.typo3.org/view.php?id=9058), it is recommended to use the extension as a userFunc until this bug is fixed! 

_The bug still exists 1.5 years after reporting it, so I guess bugfixing is not high on the TYPO3 core members priority list :(_