Changeset 27303 for main/trunk/greenstone2/perllib/classify.pm

Timestamp:

2013-05-06T15:23:45+12:00 (11 years ago)

Author:

jmt12

Message:

Replacing hardcoded additions to INC and PATH environment variables with conditional ones - this allows us to use the order of values in these variables for precedence, thus allows better support for extensions that override classifiers, plugins etc. ENV and PATH functions already exists in util, but augmentINC() is a new function

File:

• main/trunk/greenstone2/perllib/classify.pm (modified) (4 diffs)

main/trunk/greenstone2/perllib/classify.pm

@@ -29 +29 @@
 
 require util;
+use FileUtils;
 require AllList;
 
@@ -46 +47 @@
 
     # find the classifier
-    my $customclassname;
+    # - used to have hardcoded list of places to load classifier from. We
+    # should, instead, try loading from all of the perllib places on the
+    # library path, as that improves support for extensions. Special cases
+    # needed for collection specific and custom classifier. [jmt12]
+    my @possible_class_paths;
     if (defined($ENV{'GSDLCOLLECTION'}))
     {
-    $customclassname = &util::filename_cat($ENV{'GSDLCOLLECTDIR'}, "custom", $ENV{'GSDLCOLLECTION'},
-                                              "perllib", "classify", "${classifier}.pm");
-    }
-    my $colclassname = &util::filename_cat($ENV{'GSDLCOLLECTDIR'}, "perllib", "classify", "${classifier}.pm");
-    my $mainclassname = &util::filename_cat($ENV{'GSDLHOME'}, "perllib", "classify", "${classifier}.pm");
-
-    if (defined($customclassname) && -e $customclassname) { require $customclassname; }
-    elsif (-e $colclassname) { require $colclassname; }
-    elsif (-e $mainclassname) { require $mainclassname; }
-    else { 
-    &gsprintf(STDERR, "{classify.could_not_find_classifier}\n", $classifier) && die "\n";
-    }
+      push(@possible_class_paths, &FileUtils::filenameConcatenate($ENV{'GSDLCOLLECTDIR'}, 'custom', $ENV{'GSDLCOLLECTION'}, 'perllib', 'classify', $classifier . '.pm'));
+    }
+    # (why does GSDLCOLLECTDIR get set to GSDLHOME for classinfo calls?)
+    if ($ENV{'GSDLCOLLECTDIR'} ne $ENV{'GSDLHOME'})
+    {
+      push(@possible_class_paths, &FileUtils::filenameConcatenate($ENV{'GSDLCOLLECTDIR'}, 'perllib', 'classify', $classifier . '.pm'));
+    }
+    foreach my $library_path (@INC)
+    {
+      # only interested in classify paths found in the library paths
+      if ($library_path =~ /classify$/)
+      {
+       push(@possible_class_paths, &FileUtils::filenameConcatenate($library_path, $classifier . '.pm'));
+      }
+    }
+    my $found_class = 0;
+    foreach my $possible_class_path (@possible_class_paths)
+    {
+      if (-e $possible_class_path)
+      {
+        require $possible_class_path;
+        $found_class = 1;
+        last;
+      }
+    }
+    if (!$found_class)
+    {
+      &gsprintf(STDERR, "{classify.could_not_find_classifier}\n", $classifier) && die "\n";
+    }
+
     my ($classobj);
     my $options = "-gsdlinfo";
@@ -74 +97 @@
     my $classify_number  = 1;
 
-     my $colclassdir = &util::filename_cat($ENV{'GSDLCOLLECTDIR'},"perllib/classify");
-     unshift (@INC, $colclassdir);
-    
+    my $colclassdir = &FileUtils::filenameConcatenate($ENV{'GSDLCOLLECTDIR'},"perllib/classify");
+    # - ensure colclassdir doesn't already exist in INC before adding, other-
+    # wise we risk clobbering classifier inheritence implied by order of paths
+    # in INC [jmt12]
+    my $inc_paths = join(':',@INC);
+    if ($inc_paths !~ /$colclassdir/)
+    {
+      unshift (@INC, $colclassdir);
+    }
+
     foreach my $classifyoption (@$classify_list) {
 
@@ -84 +114 @@
 
     # find the classifier
-        my $customclassname = &util::filename_cat($ENV{'GSDLCOLLECTDIR'}, "custom", $ENV{'GSDLCOLLECTION'},
-                                                  "perllib", "classify", "${classname}.pm");
-        my $colclassname = &util::filename_cat($ENV{'GSDLCOLLECTDIR'}, "perllib", "classify", "${classname}.pm");
-        my $mainclassname = &util::filename_cat($ENV{'GSDLHOME'}, "perllib", "classify", "${classname}.pm");
-
-    if (-e $customclassname) { require $customclassname; }
-    elsif (-e $colclassname) { require $colclassname; }
-    elsif (-e $mainclassname) { require $mainclassname; }
-    else { &gsprintf(STDERR, "{classify.could_not_find_classifier}\n", $classname) && die "\n";
-           # die "ERROR - couldn't find classifier \"$classname\"\n";
+        # - replaced as explained in load_classifier_for_info() [jmt12]
+        my @possible_class_paths;
+        if (defined($ENV{'GSDLCOLLECTION'}))
+        {
+          push(@possible_class_paths, &FileUtils::filenameConcatenate($ENV{'GSDLCOLLECTDIR'}, 'custom', $ENV{'GSDLCOLLECTION'}, 'perllib', 'classify', $classname . '.pm'));
+        }
+        # (why does GSDLCOLLECTDIR get set to GSDLHOME for classinfo calls?)
+        if ($ENV{'GSDLCOLLECTDIR'} ne $ENV{'GSDLHOME'})
+        {
+          push(@possible_class_paths,&FileUtils::filenameConcatenate($ENV{'GSDLCOLLECTDIR'}, 'perllib', 'classify', $classname . '.pm'));
+        }
+        foreach my $library_path (@INC)
+        {
+          # only interested in classify paths found in the library paths
+          if ($library_path =~ /classify$/)
+          {
+            push(@possible_class_paths, &FileUtils::filenameConcatenate($library_path, $classname . '.pm'));
+          }
+        }
+        my $found_class = 0;
+        foreach my $possible_class_path (@possible_class_paths)
+        {
+          if (-e $possible_class_path)
+          {
+            require $possible_class_path;
+            $found_class = 1;
+            last;
+          }
+        }
+        if (!$found_class)
+        {
+          &gsprintf(STDERR, "{classify.could_not_find_classifier}\n", $classname) && die "\n";
         }