Wiki In Hyper Perl

The first line of a script can call out the interpreter that is to evaluate it. This script is two perl program.

# PerlInterpreter must be the first line of the file.

Statements at the front of the script explain ownership and point readers to these pages for elaborate documentation.

Standard output will collect text encoded in html. We may write it at any time, such as in AbortScript. Here we alert the ServerDaemon that we are sending it html.

  print "Content-type: text/html\n\n";
  print '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"'."\n";
  print '"http://www.w3.org/TR/html40/loose.dtd">'."\n";
  print '<html>';

All of our commands retrieve pages from a database so we will go ahead and open it now. We derive the path to the db file from the name of the script. That way we can use one script (with links or aliases) to serve many databases. (Perl implementations vary in the best way to open dbm files. See http:wiki?DbmProblems for a discussion.)

Relative urls with a scheme prefix (like 'http:') break in mozilla, and violate RFC 2396 which closes the loophole introduced in RFC 1630.

  dbmopen(%db, $DataBase , 0666) || &AbortScript("can't open $DataBase");

Requests are passed as heavily encoded character strings that we massage (cook) into a dictionary of keyword bindings. Here we probe that input for requests we know how to handle.

  $CookedInput{browse} && &HandleBrowse;
  $CookedInput{edit}	&& &HandleEdit;
  $CookedInput{copy}	&& &HandleEdit;
  $CookedInput{links}  && &HandleLinks;
  $CookedInput{search} && &HandleSearch;

The post command is the only one that writes into the database. The dbm libraries require that we protect it from simultaneous writes. So, we'll close the db now and let HandlePost reopen & close it inside a CriticalSection should this be a post.

  dbmclose (%db);
  if ($ENV{REQUEST_METHOD} eq POST) {
	$CookedInput{post}	&& &HandlePost;
  }

Now we're done, unless we're debugging. Then we will take this opportunity to dump important bindings on the bottom of the generated page.

  # &DumpBinding(*CookedInput);
  # &DumpBinding(*old);

[What about a more liberal Wiki Naming Convention to make each symbol linkable? -- FridemarPache] [Sounds great. How about perl symbol naming on perl lines, wiki naming on wiki lines? -- IanKjos]

  # &DumpBinding(*ENV);
  print "</html>";

For changes see WikiChangeLog.

InitialComments ScriptName DataBase AbortScript DefaultTitle LinkPattern DefaultRequest RawInput FieldSeparator CookedInput LogoUrl LogoImage ScriptUrl RetrievePage EscapeMetaCharacters InPlaceUrl TranslationToken EmitCode AsAnchor AsLink SearchForm PrintBodyText HandleBrowse ConvertSpacesToTabs HandleEdit HandleLinks HandleSearch CookSpaces LockDirectory RequestLock BackupCopy DateToday ReplacePage ReleaseLock SignatureUrl HandlePost DumpBinding WikiInHyperPerl

Last edited October 21, 2003
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