- added more argument checks

- improved readability

bin/slubsipbuilder.pl

@@ -59,20 +59,20 @@ my $man;
 
 our $VERSION = '1.1';
 GetOptions(
-    "IE_directory=s"                => \$directory,
-    "ppn=s"                         => \$ppn,
-    "noppn=s"                       => \$noppn,
-    "SIP_output_path=s"             => \$output,
-    "as_zip"                        => \$as_zip,
-    "url=s"                         => \$url,
-    "external_id=s"                 => \$external_id,
-    "external_workflow=s"           => \$external_workflow,
-    "external_ISIL=s"               => \$external_isil,
-    "external_value_descr=s"        => \$external_value_descr,
-    "external_conservation_flag"    => \$external_conservation_flag,
-    "debug"                         => \$with_debug,
-    "help|?"                        => \$help,
-    "man"                           => \$man,
+    "IE_directory=s"                => \$directory,                     # required
+    "ppn=s"                         => \$ppn,                           # semi-optional
+    "noppn=s"                       => \$noppn,                         # semi-optional
+    "SIP_output_path=s"             => \$output,                        # required
+    "as_zip"                        => \$as_zip,                        # optional, default: do not zip
+    "url=s"                         => \$url,                           # optional, default: SWB Online-Katalog
+    "external_id=s"                 => \$external_id,                   # required
+    "external_workflow=s"           => \$external_workflow,             # required
+    "external_ISIL=s"               => \$external_isil,                 # optional, default: no ISIL
+    "external_value_descr=s"        => \$external_value_descr,          # required
+    "external_conservation_flag"    => \$external_conservation_flag,    # optional, default: no special conservation
+    "debug"                         => \$with_debug,                    # optional
+    "help|?"                        => \$help,                          # optional
+    "man"                           => \$man,                           # optional
 ) or pod2usage(2);
 
 if ($help)                                  { pod2usage(1); }
@@ -84,11 +84,11 @@ if (!defined $output) { confess (" you need to specify an output path, where the
 if ($output !~ m#^/#)                       { confess("you need to specify an output path using absoluet paths, $!"); }
 if (!defined $url)                          { $url = "http://swb.bsz-bw.de/sru/DB=2.1/username=/password=/";}
 if (!defined $external_conservation_flag)   { $external_conservation_flag="false"; } else { $external_conservation_flag="true"; }
-# additional checks
 if (! -d $directory)                        { confess("you need to specify an IE directory, which needs to be archived, $!"); }
 if ($directory !~ m#^/#)                    { confess("you need to specify an IE directory using absoluet paths, $!"); }
-#if (! -d $output) { confess("you need to specify an output path, where the SIP will be stored, $!"); }
-
+if ($external_id !~ m#^[a-z0-9]+$#)         { confess("you need to specify a valid external ID (^[a-z0-9]+\$)"); }
+if ($external_workflow !~ m#^[a-z0-9]+$#)   { confess("you need to specify a valid external workflow (^[a-z0-9]+\$)"); }
+if (!$external_value_descr)                 { confess("you need to specify a external value description (reason for archiving)"); }
 
 #===============================================================================