1/*  $Id$
    2
    3    Part of SWI-Prolog
    4
    5    Author:        Jan Wielemaker
    6    E-mail:        wielemak@science.uva.nl
    7    WWW:           http://www.swi-prolog.org
    8    Copyright (C): 1985-2005, University of Amsterdam
    9
   10    This program is free software; you can redistribute it and/or
   11    modify it under the terms of the GNU General Public License
   12    as published by the Free Software Foundation; either version 2
   13    of the License, or (at your option) any later version.
   14
   15    This program is distributed in the hope that it will be useful,
   16    but WITHOUT ANY WARRANTY; without even the implied warranty of
   17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   18    GNU General Public License for more details.
   19
   20    You should have received a copy of the GNU Lesser General Public
   21    License along with this library; if not, write to the Free Software
   22    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   23
   24    As a special exception, if you link this library with other files,
   25    compiled with a Free Software compiler, to produce an executable, this
   26    library does not by itself cause the resulting executable to be covered
   27    by the GNU General Public License. This exception does not however
   28    invalidate any other reasons why the executable file might be covered by
   29    the GNU General Public License.
   30*/
   31
   32:- module(api_journal, []).   33:- use_module(library(semweb/rdf_persistency)).   34:- use_module(user(user_db)).   35:- use_module(library('http/http_parameters')).   36:- use_module(library('http/mimetype')).   37:- use_module(library('http/http_dispatch')).

   45:- http_handler(cliopatria(list_journals), list_journals, []).   46:- http_handler(cliopatria(journal),	   journal,	  []).

 list_journals(+Request)

HTTP handler to list the available journals from the persistent store as an XML document. Here is an example document:

<journals>
  <journal db="http://www.example.org/db1"/>
  <journal db="http://www.example.org/db2"/>
  ...
</journals>

See also

- /journal

   63list_journals(_Request) :- !,
   64	authorized(read(default, list_journals)),
   65	format('Content-type: text/xml~n~n'),
   66	format('<journals>~n'),
   67	forall(rdf_journal_file(DB, _File),
   68	       format('  <journal db="~w"/>~n', [DB])),
   69	format('</journals>~n').

 journal(+Request)

HTTP handler that serves the journal for an RDF named graph as a Prolog text. If no journal is available for the given named graph, it returns a 404 page.

See also

- /list_journals

   80journal(Request) :- !,
   81	http_parameters(Request,
   82			[ 'DB'(DB, [description('URI for the named graph')])
   83			],
   84			[
   85			]),
   86	authorized(read(DB, read_journal)),
   87	(   rdf_journal_file(DB, Path)
   88	->  http_reply_file(Path, [mime_type(text/'x-prolog')], Request)
   89	;   existence_error(http_location, DB)
   90	)