Difference between revisions of "API:EPrints/Plugin/Convert"

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==SYNOPSIS==
 
==SYNOPSIS==
<pre> my $root = $session-&gt;plugin( 'Convert' );</pre>
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<source lang="perl">my $root = $repo->plugin( 'Convert' );
  
<pre>  my %available = $root-&gt;can_convert( $document );</pre>
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# Get the the available conversions for all plugins
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my %available = $root->can_convert( $document );
  
<pre>  # Convert a document to plain-text
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# Get a conversion scheme for text/plain
  my $txt_tool = $available{'text/plain'};
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my $txt_tool = $available{'text/plain'};
  my $plugin = $txt_tool-&gt;{ plugin };
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  $plugin-&gt;convert( $eprint, $document, 'text/plain' );</pre>
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# Use the plugin to convert the document to text/plain
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my $plugin = $txt_tool->{'plugin'};
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$plugin->convert( $eprint, $document, 'text/plain' );</source>
  
 
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==METHODS==
 
==METHODS==
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===new===
 
===new===
  
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</source>
 
</source>
:Create a new plugin object using OPTIONS (should only be called by [[API:EPrints/Session|EPrints::Session]]).
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Create a new plugin object using OPTIONS (should only be called by [[API:EPrints/Session|EPrints::Session]]).
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===render_name===
 
===render_name===
  
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</source>
 
</source>
:Return the name of this plugin as a chunk of XHTML.
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Return the name of this plugin as a chunk of XHTML.
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===is_visible===
 
===is_visible===
  
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</source>
 
</source>
:Returns whether this plugin is visible at level (currently 'all' or '').
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Returns whether this plugin is visible at level (currently 'all' or '').
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===can_convert===
 
===can_convert===
  
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</source>
 
</source>
:Returns a hash of types that this plugin can convert the document $doc to. The key is the type. The value is a hash ref containing:
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Returns a hash of types that this plugin can convert the document $doc to. The key is the type. The value is a hash ref containing:
:
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* plugin
 
* plugin
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: The object that can do the conversion.
  
::The object that can do the conversion.
 
::
 
 
* encoding
 
* encoding
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: The encoding this conversion generates (e.g. 'utf-8').
  
::The encoding this conversion generates (e.g. 'utf-8').
 
::
 
 
* phraseid
 
* phraseid
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: A unique phrase id for this conversion.
  
::A unique phrase id for this conversion.
 
::
 
 
* preference
 
* preference
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: A value between 0 and 1 representing the 'quality' or confidence in this conversion.
  
::A value between 0 and 1 representing the 'quality' or confidence in this conversion.
 
::
 
 
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===export===
 
===export===
  
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</source>
 
</source>
:Convert $doc to $type and export it to $dir. Returns a list of file names that resulted from the conversion. The main file (if there is one) is the first file name returned. Returns empty list on failure.
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Convert $doc to $type and export it to $dir. Returns a list of file names that resulted from the conversion. The main file (if there is one) is the first file name returned. Returns empty list on failure.
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===convert===
 
===convert===
  
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</source>
 
</source>
:Convert $doc to format $type (as returned by can_convert). Stores the resulting $doc in $eprint, and returns the new document or undef on failure.
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Convert $doc to format $type (as returned by can_convert). Stores the resulting $doc in $eprint, and returns the new document or undef on failure.
:
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:Optionally initialise the new document with $epdata. Specifying 'files' in $epdata will cause the converted file content to be discarded.
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Optionally initialise the new document with $epdata. Specifying 'files' in $epdata will cause the converted file content to be discarded.
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Latest revision as of 09:56, 22 January 2013

EPrints 3 Reference: Directory Structure - Metadata Fields - Repository Configuration - XML Config Files - XML Export Format - EPrints data structure - Core API - Data Objects


API: Core API

Latest Source Code (3.4, 3.3) | Revision Log | Before editing this page please read Pod2Wiki


NAME

EPrints::Plugin::Convert - Convert EPrints::DataObj::Document into different formats


DESCRIPTION

This plugin and its dependents allow EPrints to convert documents from one format into another format. Convert plugins are also used by the full-text indexer to extract plain-text from documents.

Convert plugins may provide conversions from any number of formats to any number of other formats (or not even 'formats' per-se e.g. unpacking/packing archives). A single plugin may represent a particular software package (e.g. ImageMagick) or a common goal (e.g. textifying documents for indexing).

Using the root Convert plugin it is possible to query all loaded conversion plugins for available conversions from a given EPrints::DataObj::Document.

To allow for simpler local configuration Convert plugins should use SystemSettings to store the location of external programs.


SYNOPSIS

my $root = $repo->plugin( 'Convert' );

# Get the the available conversions for all plugins
my %available = $root->can_convert( $document );

# Get a conversion scheme for text/plain
my $txt_tool = $available{'text/plain'};

# Use the plugin to convert the document to text/plain
my $plugin = $txt_tool->{'plugin'};
$plugin->convert( $eprint, $document, 'text/plain' );


METHODS

new

new OPTIONS

Create a new plugin object using OPTIONS (should only be called by EPrints::Session).


render_name

$xhtml = $plugin->render_name

Return the name of this plugin as a chunk of XHTML.


is_visible

$plugin->is_visible( $level )

Returns whether this plugin is visible at level (currently 'all' or ).


can_convert

%types = $p->can_convert( $doc, [$type], [%params] )

Returns a hash of types that this plugin can convert the document $doc to. The key is the type. The value is a hash ref containing:

  • plugin
The object that can do the conversion.
  • encoding
The encoding this conversion generates (e.g. 'utf-8').
  • phraseid
A unique phrase id for this conversion.
  • preference
A value between 0 and 1 representing the 'quality' or confidence in this conversion.


export

@filelist = $p->export( $dir, $doc, $type )

Convert $doc to $type and export it to $dir. Returns a list of file names that resulted from the conversion. The main file (if there is one) is the first file name returned. Returns empty list on failure.


convert

$doc = $p->convert( $eprint, $doc, $type [, $epdata ] )

Convert $doc to format $type (as returned by can_convert). Stores the resulting $doc in $eprint, and returns the new document or undef on failure.

Optionally initialise the new document with $epdata. Specifying 'files' in $epdata will cause the converted file content to be discarded.


COPYRIGHT

Copyright 2000-2011 University of Southampton.

This file is part of EPrints http://www.eprints.org/.

EPrints is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

EPrints is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with EPrints. If not, see http://www.gnu.org/licenses/.