Changeset 8119

Timestamp:

2004-09-14T14:55:21+12:00 (20 years ago)

Author:

jrm21

Message:

allow multiple callbacks, one for each metadata field (using the
metadata name that greenstone sees, rather than the column name in the DB).

Updated the example file to show how to do this.

Location:

trunk/gsdl

Files:

• etc/packages/example.dbi (modified) (2 diffs)
• perllib/plugins/DBPlug.pm (modified) (5 diffs)

trunk/gsdl/etc/packages/example.dbi

@@ -67 +67 @@
 
 
-# finally, you can declare a subroutine here to process the "text"
+# finally, you can declare subroutines here to post-process the fields
 # in case you want to do any mark up or processing of it. 
 # For example, you might want to do HTML formatting.
+# The subroutine's name should be the greenstone metadata field name,
+# followed by "_callback", and must end with "}" in the first column.
 #
 #sub text_callback {
@@ -76 +78 @@
 #    return $text;
 #}
-         
+#
+#sub Title_callback {
+#    my $title=shift;
+#    return ucfirst($title); # uppercase first letter
+#}
+

trunk/gsdl/perllib/plugins/DBPlug.pm

@@ -135 +135 @@
 
     my %db_to_greenstone_fields=();
+    my %callbacks=();
 
     # read in config file.
@@ -146 +147 @@
     while (defined($line=<CONF>)) {
     chomp $line;
-    $line =~ s/\s*#.*$//mg; # remove comments
+    $line =~ s/\s*\#.*$//mg; # remove comments
     $statement .= $line;
-    if ($statement =~ m/;\s*$/) { # ends with ";"
+
+    if ($line =~ /^\}\s*$/ && $callback) { # ends the callback
+        $callback .= $statement ; $statement = "";
+        # try to check that the function is "safe"
+        if ($callback  =~ /\b(?:system|open|pipe|readpipe|qx|kill|eval|do|use|require|exec|fork)\b/ ||
+        $callback =~ /[\`]|\|\-/) {
+        # no backticks or functions that start new processes allowed
+        print $outhandle "DBPlug: bad function in callback\n";
+        return 0;
+        }
+        $callback =~ s/sub (\w+?)_callback/sub/;
+        my $fieldname=$1;
+        eval "\$callbacks{'$fieldname'} = $callback ; 1";
+        $callback="";
+    } elsif ($callback) {
+        # add this line to the callback function
+        $callback .= $statement;
+        $statement = "";
+    } elsif ($statement =~ m/;\s*$/) { # ends with ";"
         # check that it is safe
         # assignment
-        if ($statement =~ m~\$(\w+)\s* = \s*
+        if ($statement =~ m~(\$\w+)\s* = \s*
         (\d     # digits
          | ".*?(?<!\\)" # " up to the next " not preceded by a \
          | '.*?(?<!\\)' # ' up to the next ' not preceded by a \
-        )\s*;~x) {      # /x means ignore comments and whitespace in rx
-        # evaluate the assignment
-        if (!eval "\$$1=$2;") {
+        )\s*;~x ||      # /x means ignore comments and whitespace in rx
+        $statement =~ m~(\%\w+)\s*=\s*(\([\w\s\"\',:=>]+\))\s*;~ ) {   
+        # evaluate the assignment, return 1 on success "
+        if (!eval "$1=$2; 1") {
             my $err=$@;
             chomp $err;
             $err =~ s/\.$//; # remove a trailing .
-            print $outhandle "$err (in $filename)\n";
+            print $outhandle "DBPlug: error evaluating `$statement'\n";
+            print $outhandle " $err (in $filename)\n";
             return 0; # there was an error reading the config file
         }
-        } elsif ($callback) {
-        # add this line to the callback function
-        $callback .= $statement;
-        } elsif ($statement =~ /sub text_callback/) {
-        # this is the start of the callback function definition
+        } elsif ($statement =~ /sub \w+_callback/) {
+        # this is the start of a callback function definition
         $callback = $statement;
+        $statement = "";
+        } else {
+        print $outhandle "DBPlug: skipping statement `$statement'\n";
         }
         $statement = "";
-    } elsif ($statement =~ /\}\s*$/ && $callback) { # ends with {
-        $callback .= $statement ; $statement = "";
     }
     }
     close CONF;
-    if ($callback) {
-    # try to check that the function is "safe"
-    if ($callback =~ /\b(?:system|open|pipe|readpipe|qx|kill|eval|do|use|require|exec|fork)\b/ ||
-        $callback =~ /[\`]|\|\-/) {
-        # no backticks or functions that start new processes allowed
-        print $outhandle "DBPlug: bad function in callback\n";
-        return 0;
-    }
-    }
 
     if (!defined($db)) {
@@ -222 +232 @@
     }
     }
-
 
 #    print "DBPlug: names: " . join (", ", @field_names) . ".\n";
@@ -280 +289 @@
                            );
         }
+        # see if we have a ****_callback() function defined
+        if (exists $callbacks{$fieldname}) {
+        my $funcptr = $callbacks{$fieldname};
+        $fielddata = &$funcptr($fielddata);
+        }
+
         if ($fieldname eq "text") {
-        # see if we have a text_callback() function defined
-        if (defined(&text_callback)) {
-            $fielddata=text_callback($fielddata);
-        }
         # add as document text
         $fielddata=~s@<@&lt;@g;
@@ -339 +350 @@
     $self->{'num_processed'}++;
 
-    return $count;
+    if (defined($dbplug_debug) && $dbplug_debug==1) {
+        print $outhandle "DBPlug: imported $count DB records as documents.\n";
+    }
+    $count;
 }