Changeset 24403 for main/trunk

Timestamp:

2011-08-12T18:10:11+12:00 (13 years ago)

Author:

ak19

Message:

Dr Bainbridge has fixed the conflict between OAIPlugin and EmbeddedMetadataPlugin which resulted in the oai tutorial (with the JCDL pictures) going wrong: meta was not attached to the images. Dr Bainbridge solved the problem by introducing a new method in BasePlugin: can_process_this_file_for_metadata, which by default returns undef so that things should work by default mostly. This method has been overridden in OAIPlugin and EmbeddedMetadataPlugin now to do the right thing there.

Location:

main/trunk/greenstone2/perllib/plugins

Files:

• BasePlugin.pm (modified) (2 diffs)
• EmbeddedMetadataPlugin.pm (modified) (2 diffs)
• OAIPlugin.pm (modified) (2 diffs)

main/trunk/greenstone2/perllib/plugins/BasePlugin.pm

@@ -528 +528 @@
 }
 
+# Even if a plugin can extract metadata in its metadata_read pass,
+# make the default return 'undef' so processing of the file continues
+# down the pipeline, so other plugins can also have the opportunity to
+# locate metadata and set it up in the extrametakeys variables that
+# are passed around.
+
+sub can_process_this_file_for_metadata {
+    my $self = shift(@_);
+
+    return undef;
+}
+
+
 # just converts path as is to utf8.
 sub filepath_to_utf8 {
@@ -1131 +1144 @@
     # can we process this file??
     my ($filename_full_path, $filename_no_path) = &util::get_full_filenames($base_dir, $file);
-    return undef unless $self->can_process_this_file($filename_full_path);
+    return undef unless $self->can_process_this_file_for_metadata($filename_full_path);
 
     return 1; # we recognise the file, but don't actually do anything with it

main/trunk/greenstone2/perllib/plugins/EmbeddedMetadataPlugin.pm

@@ -121 +121 @@
 #}
 
+# plugins that rely on more than process_exp (eg XML plugins) can override this method
+sub can_process_this_file {
+    my $self = shift(@_);
+
+    # we process metadata, not the file 
+    return 0;    
+}
+
+# Even if a plugin can extract metadata in its metadata_read pass,
+# make the default return 'undef' so processing of the file continues
+# down the pipeline, so other plugins can also have the opportunity to
+# locate metadata and set it up in the extrametakeys variables that
+# are passed around.
+
+sub can_process_this_file_for_metadata {
+    my $self = shift(@_);
+
+    # this plugin will look for metadata in any file through its
+    # metadata_read() returning undef here means anything else further
+    # down the pipeline can do the same
+
+    return undef;
+}
+
 
 sub extractEmbeddedMetadata()
@@ -285 +309 @@
 }
 
+sub read
+{
+    return undef;
+}
 
 sub process()

main/trunk/greenstone2/perllib/plugins/OAIPlugin.pm

@@ -185 +185 @@
 }
 
+sub can_process_this_file_for_metadata {
+    my $self = shift(@_);
+
+    return $self->can_process_this_file(@_);
+}
+
 
 sub metadata_read {
@@ -195 +201 @@
     # can we process this file??
     my ($filename_full_path, $filename_no_path) = &util::get_full_filenames($base_dir, $file);
-    return undef unless $self->can_process_this_file($filename_full_path);
+    return undef unless $self->can_process_this_file_for_metadata($filename_full_path);
     
     if (!$self->parse_file($filename_full_path, $file, $gli)) {