Difference between revisions of "API:EPrints/DataObj/File"

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<!-- Pod2Wiki=_preamble_  
 
<!-- Pod2Wiki=_preamble_  
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This page has been automatically generated from the EPrints 3.2 source. Any wiki changes made between the 'Pod2Wiki=*' and 'Edit below this comment' comments will be lost.
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This page has been automatically generated from the EPrints 3.4 source. Any wiki changes made between the 'Pod2Wiki=*' and 'Edit below this comment' comments will be lost.
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  -->{{API}}{{Pod2Wiki}}{{API:Source|file=EPrints/DataObj/File.pm|package_name=EPrints::DataObj::File}}[[Category:API|FILE]][[Category:API:EPrints/DataObj|FILE]][[Category:API:EPrints/DataObj/File|FILE]]<div><!-- Edit below this comment -->
+
  -->{{API}}{{Pod2Wiki}}{{API:Source|file=EPrints/DataObj/File.pm|package_name=EPrints::DataObj::File}}[[Category:API|FILE]][[Category:API:EPrints/DataObj|FILE]]<div><!-- Edit below this comment -->
  
  
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<!-- Pod2Wiki=head_description -->
 
<!-- Pod2Wiki=head_description -->
 
==DESCRIPTION==
 
==DESCRIPTION==
−
This class contains the technical metadata associated with a file. A file is a sequence of bytes stored in the storage layer (a "stored object"). Utility methods for storing and retrieving the stored object from the storage layer are made available.
+
This class contains the technical metadata associated with a file. A file is a sequence of bytes stored in the storage layer (a "stored object"). Utility methods for storing and retrieving the stored object from the storage layer are made available.
  
−
Revision numbers on File work slightly differently to other objects. A File is only revised when it's stored object is changed and not when changes to it's metadata are made.
+
Revision numbers on File work slightly differently to other objects. A File is only revised when it's stored object is changed and not when changes to it's metadata are made.
  
 
This class is a subclass of [[API:EPrints/DataObj/SubObject|EPrints::DataObj::SubObject]].
 
This class is a subclass of [[API:EPrints/DataObj/SubObject|EPrints::DataObj::SubObject]].
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<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
 
</div>
 
</div>
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<!-- Pod2Wiki=head_core_fields -->
+
<!-- Pod2Wiki=head_core_metadata_fields -->
−
==CORE FIELDS==
+
==CORE METADATA FIELDS==
 
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</div>
 
</div>
 
<!-- Pod2Wiki=item_fileid -->
 
<!-- Pod2Wiki=item_fileid -->
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===fileid===
+
===fileid (counter)===
  
 
Unique identifier for this file.
 
Unique identifier for this file.
−
 
−
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<!-- Pod2Wiki=item_rev_number -->
 
−
===rev_number (int)===
 
−
 
−
The number of the current revision of this file.
 
  
 
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</div>
 
</div>
 
<!-- Pod2Wiki=item_datasetid -->
 
<!-- Pod2Wiki=item_datasetid -->
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===datasetid===
+
===datasetid (id)===
  
 
Id of the dataset of the parent object.
 
Id of the dataset of the parent object.
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</div>
 
</div>
 
<!-- Pod2Wiki=item_objectid -->
 
<!-- Pod2Wiki=item_objectid -->
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===objectid===
+
===objectid (int)===
  
 
Id of the parent object.
 
Id of the parent object.
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</div>
 
</div>
 
<!-- Pod2Wiki=item_filename -->
 
<!-- Pod2Wiki=item_filename -->
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===filename===
+
===filename (id)===
  
 
Name of the file (may contain directory separators).
 
Name of the file (may contain directory separators).
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</div>
 
</div>
 
<!-- Pod2Wiki=item_mime_type -->
 
<!-- Pod2Wiki=item_mime_type -->
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===mime_type===
+
===mime_type (id)===
  
 
MIME type of the file (e.g. "image/png").
 
MIME type of the file (e.g. "image/png").
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</div>
 
</div>
 
<!-- Pod2Wiki=item_hash -->
 
<!-- Pod2Wiki=item_hash -->
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===hash===
+
===hash (id)===
  
 
Check sum of the file.
 
Check sum of the file.
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</div>
 
</div>
 
<!-- Pod2Wiki=item_hash_type -->
 
<!-- Pod2Wiki=item_hash_type -->
−
===hash_type===
+
===hash_type (id)===
  
 
Name of check sum algorithm used (e.g. "MD5").
 
Name of check sum algorithm used (e.g. "MD5").
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</div>
 
</div>
 
<!-- Pod2Wiki=item_filesize -->
 
<!-- Pod2Wiki=item_filesize -->
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===filesize===
+
===filesize (bigint)===
  
 
Size of the file in bytes.
 
Size of the file in bytes.
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</div>
 
</div>
 
<!-- Pod2Wiki=item_mtime -->
 
<!-- Pod2Wiki=item_mtime -->
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===mtime===
+
===mtime (timestamp)===
  
 
Last modification time of the file.
 
Last modification time of the file.
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</div>
 
</div>
 
<!-- Pod2Wiki=item_url -->
 
<!-- Pod2Wiki=item_url -->
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===url===
+
===url (url)===
  
 
Virtual field for storing the file's URL.
 
Virtual field for storing the file's URL.
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</div>
 
</div>
 
<!-- Pod2Wiki=item_data -->
 
<!-- Pod2Wiki=item_data -->
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===data===
+
===data (base64)===
  
 
Virtual field for storing the file's content.
 
Virtual field for storing the file's content.
 +
 +
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<!-- Pod2Wiki= -->
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</div>
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<!-- Pod2Wiki=head_references_and_related_objects -->
 +
==REFERENCES AND RELATED OBJECTS==
 +
None.
 +
 +
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</div>
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<!-- Pod2Wiki=head_instances_variables -->
 +
==INSTANCES VARIABLES==
 +
See [[API:EPrints/DataObj#INSTANCE_VARIABLES|EPrints::DataObj]].
  
 
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  $dataobj = EPrints::DataObj::File-&gt;new_from_filename( $session, $dataobj, $filename )
 
  $dataobj = EPrints::DataObj::File-&gt;new_from_filename( $session, $dataobj, $filename )
−
Convenience method to get an existing File object for $filename stored in $dataobj.
+
Convenience method to return an existing file object for <tt>$filename</tt>  stored in <tt>$dataobj</tt>.
  
−
Returns undef if no such record exists.
+
Returns <tt>undef</tt> if no such record exists.
  
 
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====create_from_data====
 
====create_from_data====
  
−
  $dataobj = EPrints::DataObj::File-&gt;create_from_data( $session, $data [, $dataset ] )
+
  $dataobj = EPrints::DataObj::File-&gt;create_from_data( $session, $data, $dataset )
−
Create a new File record using $data.
+
Returns a new file record using <tt>$data</tt> and the file <tt>$dataset</tt>.
  
 
Private data elements:
 
Private data elements:
  
−
  _content - content to pass to [[API:EPrints/DataObj/File#set_file|set_file]].
+
_content - content to pass to [[API:EPrints/DataObj/File#set_file|set_file]].
−
  _filepath - path to source file used for improved mime-type detection
+
_filepath - path to source file used for improved mime-type detection
 
    
 
    
 
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====get_system_field_info====
 
====get_system_field_info====
  
−
  $thing = EPrints::DataObj::File-&gt;get_system_field_info
+
  $fields = EPrints::DataObj::File-&gt;get_system_field_info
−
Core fields.
+
Returns an array describing the system metadata fields of the file  dataset.
  
 
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  $dataset = EPrints::DataObj::File-&gt;get_dataset_id
 
  $dataset = EPrints::DataObj::File-&gt;get_dataset_id
−
Returns the id of the [[API:EPrints/DataSet|EPrints::DataSet]] object to which this record belongs.
+
Returns the ID of the [[API:EPrints/DataSet|EPrints::DataSet]] object to which this record belongs.
  
 
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  $new_file = $file-&gt;clone( $parent )
 
  $new_file = $file-&gt;clone( $parent )
−
Clone the $file object (including contained files) and return the new object.
+
Clone the file object (including contained files) and return the new object. Uses <tt>$parent</tt> to set the <tt>objectid</tt> of the cloned file data object, in case this needs to be different to the original.
  
 
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  $success = $file-&gt;remove
 
  $success = $file-&gt;remove
−
Delete the stored file.
+
Delete the file data object and the file it stores.
 +
 
 +
Returns boolean depending on the success of removing this file.
 +
 
 +
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<span style='display:none'>User Comments</span>
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<!-- Edit below this comment -->
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 +
 
 +
<!-- Pod2Wiki= -->
 +
</div>
 +
<!-- Pod2Wiki=item_update -->
 +
====update====
 +
 
 +
$file-&gt;update( $epdata )
 +
Updates the metadata for the file with <tt>$epdata</tt>.
  
 
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====get_local_copy====
 
====get_local_copy====
  
−
  $filename = $file-&gt;get_local_copy()
+
  $filename = $file-&gt;get_local_copy
−
Return the name of a local copy of the file (may be a {{API:PodLink|file=File/Temp|package_name=File::Temp|section=|text=File::Temp}} object).
+
Returns the name of a local copy of the file (may be a {{API:PodLink|file=File/Temp|package_name=File::Temp|section=|text=File::Temp}} object).
  
−
Will retrieve and cache the remote object if necessary.
+
Uses [[API:EPrints/Storage#get_local_copy|EPrints::Storage#get_local_copy]] which in turn calls the configured local storage plugin.
 +
 
 +
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 +
<!-- Edit below this comment -->
 +
 
 +
 
 +
<!-- Pod2Wiki= -->
 +
</div>
 +
<!-- Pod2Wiki=item_get_remote_copy -->
 +
====get_remote_copy====
 +
 
 +
$filename = $file-&gt;get_remote_copy
 +
Returns the name of a remote copy of the file (may be a {{API:PodLink|file=File/Temp|package_name=File::Temp|section=|text=File::Temp}} object).
 +
 
 +
Uses [[API:EPrints/Storage#get_local_copy|EPrints::Storage#get_local_copy]] which in turn calls the configured remote storage plugin.
  
 
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  $success = $file-&gt;add_file( $filepath, $filename [, $preserve_path ] )
 
  $success = $file-&gt;add_file( $filepath, $filename [, $preserve_path ] )
−
Read and store the contents of $filepath at $filename.
+
Reads and stores the contents of <tt>$filepath</tt> at <tt>$filename</tt>.
 +
 
 +
If <tt>$preserve_path</tt> is not <tt>true</tt> will strip any leading path in  <tt>$filename</tt>.
  
−
If $preserve_path is untrue will strip any leading path in $filename.
+
Returns a boolean depending on the success of adding the file.
  
 
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  $bytes = $file-&gt;upload( $filehandle, $filename, $filesize [, $preserve_path ] )
 
  $bytes = $file-&gt;upload( $filehandle, $filename, $filesize [, $preserve_path ] )
−
Read and store the data from $filehandle at $filename at the next revision number.
+
Reads and stores the data from <tt>$filehandle</tt> at <tt>$filename</tt> at the next revision number.
  
−
If $preserve_path is untrue will strip any leading path in $filename.
+
If <tt>$preserve_path</tt> is not <tt>true</tt> will strip any leading path in <tt>$filename</tt>.
  
 
Returns the number of bytes read from $filehandle or undef on failure.
 
Returns the number of bytes read from $filehandle or undef on failure.
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====write_copy====
 
====write_copy====
  
−
  $success = $stored-&gt;write_copy( $filename )
+
  $success = $file-&gt;write_copy( $filename )
−
Write a copy of this file to $filename.
+
Write a copy of this file to <tt>$filename</tt>.
  
−
Returns true if the written file contains the same number of bytes as the stored file.
+
Returns <tt>true</tt> if the written file contains the same number of bytes as the stored file.
  
 
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====write_copy_fh====
 
====write_copy_fh====
  
−
  $success = $stored-&gt;write_copy_fh( $filehandle )
+
  $success = $file-&gt;write_copy_fh( $filehandle )
−
Write a copy of this file to $filehandle.
+
Write a copy of this file to <tt>$filehandle</tt>.
 +
 
 +
Returns boolean depending on success of writing copy of file to the file handle.
  
 
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====generate_md5====
 
====generate_md5====
  
−
  $md5 = $stored-&gt;generate_md5
+
  $md5 = $file-&gt;generate_md5
 
Calculates and returns the MD5 for this file.
 
Calculates and returns the MD5 for this file.
 +
 +
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<!-- Edit below this comment -->
 +
 +
 +
<!-- Pod2Wiki= -->
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</div>
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<!-- Pod2Wiki=item_update_md5 -->
 +
====update_md5====
 +
 +
$md5 = $file-&gt;update_md5
 +
Generates MD5 and sets <tt>hash</tt> and <tt>has_type</tt> (as <tt>MD5</tt>) for this  file data object.
  
 
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====generate_sha====
 
====generate_sha====
  
−
  $digest = $file-&gt;generate_sha( [ ALGORITHM ] )
+
  $digest = $file-&gt;generate_sha( [ $alg ] )
−
Generate a SHA for this file, see {{API:PodLink|file=Digest/SHA/PurePerl|package_name=Digest::SHA::PurePerl|section=|text=Digest::SHA::PurePerl}} for a list of supported algorithms. Defaults to "256" (SHA-256).
+
Generates a SHA for this file, see {{API:PodLink|file=Digest/SHA|package_name=Digest::SHA|section=|text=Digest::SHA}} for a list of supported algorithms. Defaults to <tt>256</tt> (SHA-256) if <tt>$alg</tt> is not set.
  
 
Returns the hex-encoded digest.
 
Returns the hex-encoded digest.
 +
 +
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<!-- Edit below this comment -->
 +
 +
 +
<!-- Pod2Wiki= -->
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</div>
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<!-- Pod2Wiki=item_update_sha -->
 +
====update_sha====
 +
 +
$md5 = $file-&gt;update_sha
 +
Generates a SHA for this file, see {{API:PodLink|file=Digest/SHA|package_name=Digest::SHA|section=|text=Digest::SHA}} for a list of supported algorithms. Defaults to <tt>256</tt> (SHA-256) if <tt>$alg</tt> is not set. Then sets the <tt>hash</tt> and c&lt;has_type&gt; for this file data object.
 +
 +
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<span style='display:none'>User Comments</span>
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<!-- Edit below this comment -->
 +
 +
 +
<!-- Pod2Wiki= -->
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<!-- Pod2Wiki=item_to_sax -->
 +
====to_sax====
 +
 +
$file-&gt;to_sax( %opts )
 +
Generate SAX output for file data object and assign to <tt>Output</tt> of <tt>Handler</tt> specified in <tt>%opts</tt>.
  
 
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====add_plugin_copy====
 
====add_plugin_copy====
  
−
  $stored-&gt;add_plugin_copy( $plugin, $sourceid )
+
  $file-&gt;add_plugin_copy( $plugin, $sourceid )
−
Add a copy of this file stored using $plugin identified by $sourceid.
+
Add a copy of this file stored using <tt>$plugin</tt> identified by <tt>$sourceid</tt>.
  
 
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====remove_plugin_copy====
 
====remove_plugin_copy====
  
−
  $stored-&gt;remove_plugin_copy( $plugin )
+
  $file-&gt;remove_plugin_copy( $plugin )
−
Remove the copy of this file stored using $plugin.
+
Remove the copy of this file stored using <tt>$plugin</tt>.
  
 
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====get_file====
 
====get_file====
  
−
  $success = $stored-&gt;get_file( CALLBACK [, $offset, $n ] )
+
  $success = $file-&gt;get_file( $f, [ $offset, $n ] )
−
Get the contents of the stored file - see [[API:EPrints/Storage#retrieve|EPrints::Storage/retrieve]].
+
Get the contents of the stored file.
  
−
$offset is the position in bytes to start reading from, default 0.
+
<tt>$offset</tt> is the position in bytes to start reading from, defaults to  0.
  
−
$n is the number of bytes to read, default <tt>filesize</tt>.
+
<tt>$n</tt> is the number of bytes to read, defaults to <tt>filesize</tt>.
 +
 
 +
<tt>$f</tt> is:
 +
 
 +
  sub {
 +
    my( $buffer ) = @_;
 +
    ...
 +
    return 1;
 +
  }
 +
 
 +
Returns boolean dependent on whether file was successfully retrieved.
  
 
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====set_file====
 
====set_file====
  
−
  $content_length = $stored-&gt;set_file( CONTENT, $content_length )
+
  $content_length = $file-&gt;set_file( $content, $clen )
−
Reads data from CONTENT and stores it. Sets the MD5 hash and filesize.
+
Write <tt>$clen</tt> bytes from <tt>$content</tt> to the file object. Updates  <tt>filesize</tt> and <tt>hash</tt>. You must then call [[API:EPrints/DataObj/File#commit|commit]]) to save these  changes.
  
−
If the write failed returns undef and sets the filesize to 0.
+
Returns an integer for the content length or <tt>undef</tt> on failure.
  
−
CONTENT may be one of:
+
<tt>$content</tt> may be one of:
  
−
  CODEREF - will be called until it returns empty string ("")
+
CODEREF - Will be called until it returns empty string ("").
−
  SCALARREF - a scalar reference will be used as-is (expects bytes)
+
SCALARREF - A scalar reference to a string of octets that will be written as-is.
−
  GLOB - will be treated as a file handle and read with sysread()
+
GLOB - Will be treated as a file handle and read with sysread().
 
    
 
    
−
This method does not check the actual number of bytes read is the same as $content_length.
+
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 +
<span style='display:none'>User Comments</span>
 +
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 +
 
 +
 
 +
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 +
</div>
 +
<!-- Pod2Wiki=item_set_file_chunk -->
 +
====set_file_chunk====
 +
 
 +
$content_length = $file-&gt;set_file_chunk( $content, $clen, $offset, $total )
 +
Write a chunk of data to the content, overwriting or appending to the  existing content. See [[API:EPrints/DataObj/File#set_file|set_file]] for <tt>$content</tt> and <tt>$clen</tt>.  <tt>filesize</tt> is updated if <tt>$offset + $content_length</tt> is greater than  the current <tt>filesize</tt>.
 +
 
 +
<tt>$offset</tt> is the starting point (in bytes) to write. <tt>$total</tt> is the  total size of the file, used to determine where to store the content.
 +
 
 +
Returns the number of bytes written or <tt>undef</tt> on failure.
 +
 
 +
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 +
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 +
 
 +
 
 +
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 +
<!-- Pod2Wiki=item_start_element -->
 +
====start_element====
 +
 
 +
$file-&gt;start_element( $data, $epdata, $state )
 +
Consumes a SAX event.  See &lt;EPrints::DataObj#start_element&gt; for more information.
 +
 
 +
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 +
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 +
<!-- Edit below this comment -->
 +
 
 +
 
 +
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 +
<!-- Pod2Wiki=item_end_element -->
 +
====end_element====
 +
 
 +
$file-&gt;end_element( $data, $epdata, $state )
 +
Ends element from [[API:EPrints/DataObj/File#start_element|start_element]].
 +
 
 +
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 +
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 +
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 +
 
 +
 
 +
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 +
<!-- Pod2Wiki=item_characters -->
 +
====characters====
 +
 
 +
$file-&gt;characters( $data, $epdata, $state )
 +
Consumes characters within [[API:EPrints/DataObj/File#start_element|start_element]].
 +
 
 +
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 +
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 +
<!-- Edit below this comment -->
 +
 
 +
 
 +
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 +
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 +
<!-- Pod2Wiki=item_render_filesize -->
 +
====render_filesize====
 +
 
 +
EPrints::DataObj::File-&gt;render_filesize( $repo, $field, $value )
 +
Returns an XHTML DOM fragment, which is either empty if <tt>$value</tt> is not set or a human-readable rendering of this file size.
 +
 
 +
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 +
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 +
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 +
 
 +
 
 +
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 +
<!-- Pod2Wiki=item_get_url -->
 +
====get_url====
 +
 
 +
$file-&gt;get_url
 +
Returns the URL from which this file can be downloaded. 
 +
 
 +
Calls [[API:EPrints/DataObj/Document#get_url|EPrints::DataObj::Document#get_url]] on the parent object for this file with the <tt>filename</tt> as a parameter.
 +
 
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 +
====path====
 +
 
 +
$file-&gt;path
 +
Returns the filesystem path for this file.
  
 
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==COPYRIGHT==
 
==COPYRIGHT==
 +
{{API:Copyright}}
 
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<span style='display:none'>User Comments</span>

Latest revision as of 10:51, 10 January 2022

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::DataObj::File - a stored file

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DESCRIPTION

This class contains the technical metadata associated with a file. A file is a sequence of bytes stored in the storage layer (a "stored object"). Utility methods for storing and retrieving the stored object from the storage layer are made available.

Revision numbers on File work slightly differently to other objects. A File is only revised when it's stored object is changed and not when changes to it's metadata are made.

This class is a subclass of EPrints::DataObj::SubObject.

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CORE METADATA FIELDS

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fileid (counter)

Unique identifier for this file.

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datasetid (id)

Id of the dataset of the parent object.

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objectid (int)

Id of the parent object.

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filename (id)

Name of the file (may contain directory separators).

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mime_type (id)

MIME type of the file (e.g. "image/png").

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hash (id)

Check sum of the file.

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hash_type (id)

Name of check sum algorithm used (e.g. "MD5").

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filesize (bigint)

Size of the file in bytes.

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mtime (timestamp)

Last modification time of the file.

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url (url)

Virtual field for storing the file's URL.

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data (base64)

Virtual field for storing the file's content.

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REFERENCES AND RELATED OBJECTS

None.

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INSTANCES VARIABLES

See EPrints::DataObj.

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METHODS

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Constructor Methods

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new_from_filename

$dataobj = EPrints::DataObj::File->new_from_filename( $session, $dataobj, $filename )

Convenience method to return an existing file object for $filename stored in $dataobj.

Returns undef if no such record exists.

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create_from_data

$dataobj = EPrints::DataObj::File->create_from_data( $session, $data, $dataset )

Returns a new file record using $data and the file $dataset.

Private data elements: 

_content - content to pass to set_file.
_filepath - path to source file used for improved mime-type detection

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Class Methods

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get_system_field_info

$fields = EPrints::DataObj::File->get_system_field_info

Returns an array describing the system metadata fields of the file dataset.

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get_dataset_id

$dataset = EPrints::DataObj::File->get_dataset_id

Returns the ID of the EPrints::DataSet object to which this record belongs.

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Object Methods

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clone

$new_file = $file->clone( $parent )

Clone the file object (including contained files) and return the new object. Uses $parent to set the objectid of the cloned file data object, in case this needs to be different to the original.

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remove

$success = $file->remove

Delete the file data object and the file it stores.

Returns boolean depending on the success of removing this file.

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update

$file->update( $epdata )

Updates the metadata for the file with $epdata.

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get_local_copy

$filename = $file->get_local_copy

Returns the name of a local copy of the file (may be a File::Temp object).

Uses EPrints::Storage#get_local_copy which in turn calls the configured local storage plugin.

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get_remote_copy

$filename = $file->get_remote_copy

Returns the name of a remote copy of the file (may be a File::Temp object).

Uses EPrints::Storage#get_local_copy which in turn calls the configured remote storage plugin.

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add_file

$success = $file->add_file( $filepath, $filename [, $preserve_path ] )

Reads and stores the contents of $filepath at $filename.

If $preserve_path is not true will strip any leading path in $filename.

Returns a boolean depending on the success of adding the file.

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upload

$bytes = $file->upload( $filehandle, $filename, $filesize [, $preserve_path ] )

Reads and stores the data from $filehandle at $filename at the next revision number.

If $preserve_path is not true will strip any leading path in $filename.

Returns the number of bytes read from $filehandle or undef on failure.

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write_copy

$success = $file->write_copy( $filename )

Write a copy of this file to $filename.

Returns true if the written file contains the same number of bytes as the stored file.

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write_copy_fh

$success = $file->write_copy_fh( $filehandle )

Write a copy of this file to $filehandle.

Returns boolean depending on success of writing copy of file to the file handle.

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generate_md5

$md5 = $file->generate_md5

Calculates and returns the MD5 for this file.

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update_md5

$md5 = $file->update_md5

Generates MD5 and sets hash and has_type (as MD5) for this file data object.

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generate_sha

$digest = $file->generate_sha( [ $alg ] )

Generates a SHA for this file, see Digest::SHA for a list of supported algorithms. Defaults to 256 (SHA-256) if $alg is not set.

Returns the hex-encoded digest.

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update_sha

$md5 = $file->update_sha

Generates a SHA for this file, see Digest::SHA for a list of supported algorithms. Defaults to 256 (SHA-256) if $alg is not set. Then sets the hash and c<has_type> for this file data object.

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to_sax

$file->to_sax( %opts )

Generate SAX output for file data object and assign to Output of Handler specified in %opts.

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add_plugin_copy

$file->add_plugin_copy( $plugin, $sourceid )

Add a copy of this file stored using $plugin identified by $sourceid.

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remove_plugin_copy

$file->remove_plugin_copy( $plugin )

Remove the copy of this file stored using $plugin.

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get_file

$success = $file->get_file( $f, [ $offset, $n ] )

Get the contents of the stored file.

$offset is the position in bytes to start reading from, defaults to 0.

$n is the number of bytes to read, defaults to filesize.

$f is: 

 sub {
   my( $buffer ) = @_;
   ...
   return 1;
 }

Returns boolean dependent on whether file was successfully retrieved.

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set_file

$content_length = $file->set_file( $content, $clen )

Write $clen bytes from $content to the file object. Updates filesize and hash. You must then call commit) to save these changes.

Returns an integer for the content length or undef on failure.

$content may be one of: 

CODEREF - Will be called until it returns empty string ("").
SCALARREF - A scalar reference to a string of octets that will be written as-is.
GLOB - Will be treated as a file handle and read with sysread().

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set_file_chunk

$content_length = $file->set_file_chunk( $content, $clen, $offset, $total )

Write a chunk of data to the content, overwriting or appending to the existing content. See set_file for $content and $clen. filesize is updated if $offset + $content_length is greater than the current filesize.

$offset is the starting point (in bytes) to write. $total is the total size of the file, used to determine where to store the content.

Returns the number of bytes written or undef on failure.

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start_element

$file->start_element( $data, $epdata, $state )

Consumes a SAX event. See <EPrints::DataObj#start_element> for more information.

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end_element

$file->end_element( $data, $epdata, $state )

Ends element from start_element.

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characters

$file->characters( $data, $epdata, $state )

Consumes characters within start_element.

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render_filesize

EPrints::DataObj::File->render_filesize( $repo, $field, $value )

Returns an XHTML DOM fragment, which is either empty if $value is not set or a human-readable rendering of this file size.

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get_url

$file->get_url

Returns the URL from which this file can be downloaded.

Calls EPrints::DataObj::Document#get_url on the parent object for this file with the filename as a parameter.

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path

$file->path

Returns the filesystem path for this file.

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SEE ALSO

EPrints::DataObj and EPrints::DataSet.

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COPYRIGHT

© Copyright 2000-2024 University of Southampton.

EPrints 3.4 is supplied by EPrints Services.

http://www.eprints.org/eprints-3.4/

LICENSE

This file is part of EPrints 3.4 http://www.eprints.org/.

EPrints 3.4 and this file are released under the terms of the GNU Lesser General Public License version 3 as published by the Free Software Foundation unless otherwise stated.

EPrints 3.4 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 3.4. If not, see http://www.gnu.org/licenses/.

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