From: Stefano Zacchiroli <zack@upsilon.cc>
Date: Tue, 26 Jun 2001 14:48:51 +0000 (+0000)
Subject: * added preliminary support for rdf metadata
X-Git-Tag: v0_1_3~135
X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=commitdiff_plain;h=2743bf654edf44411fb0c0a64bbe485c6bc5c864;p=helm.git

* added preliminary support for rdf metadata
 - "getxml" method return also rdf metadata
 - "update" method update both urls_of_uris and rdf db
 - "resolve" method resolve both normal and rdf uris
* added sub isRdfUri
* added sub resolve
* changed VERSION var in configure.in, now in sync with cvs repository
  version .. :-)
---

diff --git a/helm/http_getter/configure.in b/helm/http_getter/configure.in
index 13ba5aee7..a678fb2d0 100644
--- a/helm/http_getter/configure.in
+++ b/helm/http_getter/configure.in
@@ -2,8 +2,8 @@ AC_INIT(http_getter.pl.in)
 
 PACKAGE=helm_http_getter
 MAJOR_VERSION=0
-MINOR_VERSION=0
-MICRO_VERSION=2
+MINOR_VERSION=1
+MICRO_VERSION=45
 VERSION=$MAJOR_VERSION.$MINOR_VERSION.$MICRO_VERSION
 
 DEFAULT_HELM_LIB_DIR=/usr/local/lib/helm
diff --git a/helm/http_getter/http_getter.pl.in b/helm/http_getter/http_getter.pl.in
index 7017d1957..1daadef7b 100755
--- a/helm/http_getter/http_getter.pl.in
+++ b/helm/http_getter/http_getter.pl.in
@@ -30,7 +30,7 @@ my $VERSION = "@VERSION@";
 # various variables
 my ($HELM_LIB_PATH);
 my $cgi_dir = "@HELM_CGI_DIR@";
-my (%map);
+my (%map, %rdf_map);
 
 # First of all, let's load HELM configuration
 use Env;
@@ -52,9 +52,16 @@ if (($cachemode ne 'gzipped') and ($cachemode ne 'normal')) {
 }
 # </ZACK>
 
-# next require defines: $helm_dir, $html_link, $dtd_dir, $uris_dbm
+# next require defines: $helm_dir, $html_link, $dtd_dir, $uris_dbm, $indexname
 require $HELM_LIB_PATH;
 
+# TEMP: TODO put these vars in configuration file configuration.xml
+# <move_to_conf_file>
+$helm_rdf_dir = "/usr/local/helm/rdf";
+$rdf_dbm = "/usr/local/helm/rdf_urls";
+$rdf_indexname = "rdf_index.txt";
+# </move_to_conf_file>
+
 # Let's override the configuration file
 $style_dir = $ENV{"HELM_STYLE_DIR"} if (defined ($ENV{"HELM_STYLE_DIR"}));
 $dtd_dir = $ENV{"HELM_DTD_DIR"} if (defined ($ENV{"HELM_DTD_DIR"}));
@@ -83,13 +90,22 @@ $myownurl  =~ s/http:\/\/(.*):(.*)/$1/;
 ($myownurl) = gethostbyname($myownurl);
 $myownurl = "http://".$myownurl.":".$myownport;
 
-tie(%map, 'DB_File', $uris_dbm.".db", O_RDWR, 0664);
+tie(%map, 'DB_File', $uris_dbm.".db", O_RDWR, 0664); # open dbs
+tie(%rdf_map, 'DB_File', $rdf_dbm.".db", O_RDWR, 0664);
+
+print "\n";
+print "HTTP Getter $VERSION\n"; # print hello information
 print "Please contact me at: <URL:", $myownurl."/", ">\n";
+print "\n";
 print "helm_dir: $helm_dir\n";
+print "helm_rdf_dir: $helm_rdf_dir\n";
 print "style_dir: $style_dir\n";
 print "dtd_dir: $dtd_dir\n";
 print "urls_of_uris.db: $uris_dbm.db\n";
 print "cache mode: $cachemode\n";
+print "indexname: $indexname\n";
+print "rdf_indexname: $rdf_indexname\n";
+print "\n";
 
 $SIG{CHLD} = "IGNORE"; # do not accumulate defunct processes
 $SIG{USR1} = \&update; # sent by the child to make the parent update
@@ -107,9 +123,10 @@ while (my $c = $d->accept) {
 
 	print "\nUnescaped query: ".$http_query."\n";
 
+         # "getxml" works with rdf uris
         if ($http_method eq 'GET' and $http_path eq "/getxml") {
             # finds the uri, url and filename
-            my $cicuri = $inputuri;
+
             my $answerformat = $cgi->param('format');
             my $patch_dtd = $cgi->param('patch_dtd');
             $answerformat = "" if (not defined($answerformat));
@@ -124,41 +141,53 @@ while (my $c = $d->accept) {
              die "Wrong param, patch_dtd must be 'yes' or 'no'\n";
             }
 
-            my $cicfilename = $cicuri;
-            $cicfilename =~ s/cic:(.*)/$1/;
-            $cicfilename =~ s/theory:(.*)/$1/;
+            my $filename = $inputuri;
+            if (not isRdfUri($inputuri)) { # standad cic: or theory: uri
+             $filename =~ s/^cic:(.*)/$1/;
+             $filename =~ s/^theory:(.*)/$1/;
+            } else { # rdf uri
+             $filename =~ s/^(.*)\/\/cic:(.*)/$2/;
+             $filename =~ s/^(.*)\/\/theory:(.*)/$2/;
+            }
 
-            my $cicurl   = $map{$cicuri};
-            if (not defined($cicurl)) {
-             die "uri \"$cicuri\" can't be resolved\n";
+            my $url = resolve ($inputuri); # resolve uri in url
+            if (not defined($url)) {
+             die "uri \"$inputuri\" can't be resolved\n";
             }
-            my $extension;
-            if ($cicurl =~ /\.xml$/) { # non gzipped file
+
+            my $extension; # file extension
+            if ($url =~ /\.xml$/) { # non gzipped file
               $extension = ".xml";
-            } elsif ($cicurl =~ /\.xml\.gz$/) { # gzipped file
+            } elsif ($url =~ /\.xml\.gz$/) { # gzipped file
               $extension = ".xml.gz";
             } else { # error: unknown extension
-             die "unexpected extension in url: $cicurl, might be '.xml'".
+             die "unexpected extension in url: $url, might be '.xml'".
               "or '.xml.gz'";
             }
-            $cicfilename = $helm_dir.$cicfilename.$extension;
 
-            if (!defined($cicurl)) {
+            if (not isRdfUri ($inputuri)) {
+             $filename = $helm_dir.$filename.$extension;
+            } else {
+             $filename = $helm_rdf_dir.$filename.$extension;
+            }
+
+            if (!defined($url)) {
              print "\nNOT FOUND!!!!!\n";
              $c->send_error(RC_NOT_FOUND)
             } else {
-               print_request("cic",$cicuri,$cicurl,$cicfilename);
+               print_request("cic",$inputuri,$url,$filename);
 
                # Retrieves the file
-               my $ciccontent = download($patch_dtd,"cic",$cicurl,$cicfilename,$answerformat);
+               my $ciccontent = download($patch_dtd,"cic",$url,$filename,$answerformat);
 
                # Answering the client
-	       if ($answerformat eq "normal") {
+               if ($answerformat eq "normal") {
                 answer($c,$ciccontent,"text/xml","");
                } else {
                 answer($c,$ciccontent,"text/xml","x-gzip");
                }
             }
+          # "/register" does not work with rdf uris
         } elsif ($http_method eq 'GET' and $http_path eq "/register") {
           my $inputurl = $cgi->param('url');
           print "Register requested...\n";
@@ -177,8 +206,10 @@ while (my $c = $d->accept) {
           untie %map;
           print "done\n";
           html_nice_answer($c,"Register done");
+          # "/resolve" works with rdf uri
         } elsif ($http_method eq 'GET' and $http_path eq "/resolve") {
-          my $outputurl = $map{$inputuri};
+          #my $outputurl = $map{$inputuri};
+          my $outputurl = resolve($inputuri);
           $outputurl = "" if (not defined($outputurl));
           $cont = "<?xml version=\"1.0\" ?>\n\n";
           if ($outputurl eq "") {
@@ -242,12 +273,13 @@ while (my $c = $d->accept) {
                die "Could not find XSLT!";
             }
         } elsif ($http_method eq 'GET' and $http_path eq "/update") {
-            # rebuild urls_of_uris.db
+            # rebuild urls_of_uris db and rdf uris db
            print "Update requested...\n";
-           mk_urls_of_uris();
+           update_dbs();
            kill(USR1,getppid()); # signal changes to parent
            print " done\n";
            html_nice_answer($c,"Update done");
+          # "/ls" does not work with rdf uris
         } elsif ($http_method eq 'GET' and $http_path eq "/ls") {
             # send back keys that begin with a given uri
            my ($uritype,$uripattern,$uriprefix);
@@ -286,9 +318,11 @@ while (my $c = $d->accept) {
              "'cic:' or 'theory:'");
            }
         } elsif ($http_method eq 'GET' and $http_path eq "/help") {
+          # help request
            print "Help requested!\n";
            html_nice_answer($c,"HTTP Getter Version: $VERSION");
         } elsif ($http_method eq 'GET' and $http_path =~ /\.cgi$/) {
+          # cgi handling
            print "CGI requested!\n";
            if ($http_path !~ /^\/[^\/]*\.cgi$/) {
             html_nice_answer($c,"Invalid CGI name: $http_path, ".
@@ -309,7 +343,7 @@ while (my $c = $d->accept) {
             html_nice_answer($c,"CGI '$http_path' not found ".
              "in CGI dir '$cgi_dir'");
            }
-        } else {
+        } else { # unsupported request
             print "\n";
             print "INVALID REQUEST!!!!!\n";
             print "(PATH: ",$http_path,", ";
@@ -327,6 +361,31 @@ while (my $c = $d->accept) {
 
 #================================
 
+sub isRdfUri { # return true if the uri is an rdf uri, false otherwise
+# typycal rdf uri:
+# helm:rdf/cic:www.cs.unibo.it/helm/rdf/foo_schema//cic:\
+#  /Coq/Init/Logic/True_rec.con.types.xml.gz
+#
+# the format is "helm:rdf/<metadata_tree>:<metadata_scheme>//<xml_file_uri>"
+#
+ my ($uri) = @_;
+ if ($uri =~ /^helm:rdf\/(.*):?(.*)\/\/(.*)/) {
+  return 1;
+ } else {
+  return 0;
+ }
+}
+
+sub resolve { # resolve an uri in a url, work both with standard cic: or theory:
+              # uris and rdf uris
+ my ($uri) = @_;
+ if (isRdfUri ($uri)) { # rdf uri, resolve using rdf db
+  return ($rdf_map{$uri});
+ } else { # standard cic: or theory: uri, resolve using std uri db
+  return ($map{$uri});
+ }
+}
+
 sub finduris { # find uris for cic and theory trees generation
  my ($uritype,$uripattern,$format) = @_;
  my $content = "";
@@ -656,35 +715,45 @@ sub helm_wget {
 sub update {
  untie %map;
  tie(%map, 'DB_File', $uris_dbm.".db", O_RDWR, 0664);
+ untie %rdf_map;
+ tie(%rdf_map, 'DB_File', $uris_dbm.".db", O_RDWR, 0664);
 }
 
-sub mk_urls_of_uris {
-#rebuild $uris_dbm.db fetching resource indexes from servers
+sub update_dbs {
+# rebuild dbs fetching resource indexes from servers.
+# Rebuild urls_of_uris db (1) and rdf db (2)
  my (
-  $server, $idxfile, $uri, $url, $comp, $line,
+  $server, $idxfile, $rdf_idxfile, $uri, $url, $comp, $line,
   @servers,
-  %urls_of_uris
+  %urls_of_uris, %rdf # local proxy of $map and $rdf_map
  );
 
  untie %map;
- if (stat $uris_dbm.".db") { # remove old db file
-  unlink($uris_dbm.".db") or
-   die "cannot unlink old db file: $uris_dbm.db\n";
+ untie %rdf_map;
+ foreach my $file ($uris_dbm, $rdf_dbm) { # remove old db file
+  if (stat $file.".db") { # remove if exists
+   unlink ($file.".db") or die "can't unlink old db file: $file.db\n";
+  }
  }
  tie(%urls_of_uris, 'DB_File', $uris_dbm.".db", O_RDWR|O_CREAT, 0664);
+ tie(%rdf, 'DB_File', $rdf_dbm.".db", O_RDWR|O_CREAT, 0664);
 
  open (SRVS, "< $servers_file") or
   die "cannot open servers file: $servers_file\n";
- @servers = <SRVS>;
+ @servers = <SRVS>; # read all servers
  close (SRVS);
- while ($server = pop @servers) { #cicle on servers in reverse order
+
+ while ($server = pop @servers) { # cicle on servers in _reverse_ order
   print "processing server: $server ...\n";
   chomp $server;
-  helm_wget($tmp_dir, $server."/".$indexname); #get index
+  helm_wget($tmp_dir, $server."/".$indexname); # get index
+  helm_wget($tmp_dir, $server."/".$rdf_indexname); # get rdf index
   $idxfile = $tmp_dir."/".$indexname;
-  open (INDEX, "< $idxfile") or
+  $rdf_idxfile = $tmp_dir."/".$rdf_indexname;
+
+  open (INDEX, "< $idxfile") or # (1) REBUILD URLS_OF_URIS DB
    die "cannot open temporary index file: $idxfile\n";
-  while ($line = <INDEX>) { #parse index and add entry to urls_of_uris
+  while ($line = <INDEX>) {  # parse index and add entry to urls_of_uris db
    chomp $line;
    ($uri,$comp) = split /[ \t]+/, $line;
              # build url:
@@ -697,12 +766,35 @@ sub mk_urls_of_uris {
    $url =~ s/theory:/$server/;
    $urls_of_uris{$uri} = $url;
   }
-  close INDEX;
-  die "cannot unlink temporary file: $idxfile\n"
+
+  open (RDF_INDEX, "< $rdf_idxfile") or # (2) REBUILD RDF DB
+   die "cannot open temporary rdf index file: $rdf_idxfile\n";
+  while ($line = <RDF_INDEX>) {  # parse index and add entry to rdf db
+   chomp $line;
+   ($uri,$comp) = split /[ \t]+/, $line; # comp is "gz" or nothing
+             # build url:
+   if ($comp =~ /gz/) { 
+    $url = $uri . ".xml" . ".gz";
+   } else {
+    $url = $uri . ".xml";
+   }
+   $url =~ s/^helm:rdf(.*)\/\/cic:/$server/;
+   $url =~ s/^helm:rdf(.*)\/\/theory:/$server/;
+   $rdf{$uri} = $url;
+  }
+
+  close INDEX;  # close indexes
+  close RDF_INDEX;
+  die "cannot unlink temporary file: $idxfile\n"  # remove temp files
    if (unlink $idxfile) != 1;
+  die "cannot unlink temporary file: $rdf_idxfile\n"
+   if (unlink $rdf_idxfile) != 1;
+
  }
 
- untie(%urls_of_uris);
- tie(%map, 'DB_File', $uris_dbm.".db", O_RDWR, 0664);
-}
+ untie(%urls_of_uris); # untie local proxies
+ untie(%rdf);
+ tie(%map, 'DB_File', $uris_dbm.".db", O_RDWR, 0664); # retie global ones
+ tie(%rdf_map, 'DB_File', $rdf_dbm.".db", O_RDWR, 0664);
+} # update_dbs