Item5954: DirectedGraphPlugin should permit direct file I/O

• Plugin needs a way to bypass the TWiki attachment API and write directly to the file system
• The plugin needs to generate links for all generated file types if the files are not visible in the attachments table.

See also TWiki:Codev/UnversionedAttachments and TWiki:Plugins/DirectedGraphPluginDev

This item will add a couple of additional configuration variables:

• $TWiki::cfg{DirectedGraphPlugin}{attachPath} = '';
• $TWiki::cfg{DirectedGraphPlugin}{attachUrlPath} = '';

There is a possibility that doing direct file I/O will improve the attachment speed by bypassing the revision control processing. Also, by doing direct file I/O, the user "viewing" the topic will not need update permission if the generated attachments change.

If these parameters are not set, then the plugin will use the standard attachment API as in previous versions. If they are configured, then the plugin will store generated attachments in the specified path, and will generate links using the specified URL path.

In addition a configuration parameter FORCEATTACHAPI, if enabled, will ignore these parameters and create all attachments using the standard API.

Finally, a <dot> parameter and configuration parameter, linkattachments, will cause the plugin to generate inline links for all attachment types except for the displayed inline image, in the form of [ps] [pdf] [jpg] ...

Note that for future compatibility with the store subsystem, it would be preferable to implement enhancements to the Func::saveAttachment API to permit "unversioned" attachments, and to bypass permission checking.

-- TWiki:Main/GeorgeClark - 25 Aug 2008

I've attached a test build to the TWiki:Plugins.DirectedGraphPluginDev topic. I'd appreciate some feedback on the changes before I upload a new release of the Plugin.

-- TWiki:Main.GeorgeClark - 01 Sep 2008

The version you built worked for normal cases, I did not try doing any direct I/O

Thanks,

Martin.

-- TWiki:Main.MartinCleaver - 18 Sep 2008

This is now done with latest 1.8 release Item6505.

-- TWiki:Main.PeterThoeny - 26 Jun 2010