--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/web/views/urlrewrite.py Wed Nov 05 15:52:50 2008 +0100
@@ -0,0 +1,208 @@
+"""Rules based url rewriter component, to get configurable RESTful urls
+
+:organization: Logilab
+:copyright: 2007-2008 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
+"""
+import re
+
+from cubicweb.vregistry import autoselectors
+
+from cubicweb.common.registerers import accepts_registerer
+from cubicweb.common.appobject import AppObject
+
+
+def rgx(pattern, flags=0):
+ """this is just a convenient shortcout to add the $ sign"""
+ return re.compile(pattern+'$', flags)
+
+class metarewriter(autoselectors):
+ """auto-extend rules dictionnary"""
+ def __new__(mcs, name, bases, classdict):
+ # collect baseclass' rules
+ rules = []
+ ignore_baseclass_rules = classdict.get('ignore_baseclass_rules', False)
+ if not ignore_baseclass_rules:
+ for base in bases:
+ rules[0:0] = getattr(base, 'rules', [])
+ rules[0:0] = classdict.get('rules', [])
+ inputs = set()
+ for data in rules[:]:
+ try:
+ input, output, groups = data
+ except ValueError:
+ input, output = data
+ if input in inputs:
+ rules.remove( (input, output) )
+ else:
+ inputs.add(input)
+ classdict['rules'] = rules
+ return super(metarewriter, mcs).__new__(mcs, name, bases, classdict)
+
+
+class URLRewriter(AppObject):
+ """base class for URL rewriters
+
+ url rewriters should have a `rules` dict that maps an input URI
+ to something that should be used for rewriting.
+
+ The actual logic that defines how the rules dict is used is implemented
+ in the `rewrite` method
+
+ A `priority` attribute might be used to indicate which rewriter
+ should be tried first. The higher the priority is, the earlier the
+ rewriter will be tried
+ """
+ __metaclass__ = metarewriter
+ __registry__ = 'urlrewriting'
+ __registerer__ = accepts_registerer
+ __abstract__ = True
+
+ id = 'urlrewriting'
+ accepts = ('Any',)
+ priority = 1
+
+ def rewrite(self, req, uri):
+ raise NotImplementedError
+
+
+class SimpleReqRewriter(URLRewriter):
+ """The SimpleReqRewriters uses a `rules` dict that maps
+ input URI (regexp or plain string) to a dictionary to update the
+ request's form
+
+ If the input uri is a regexp, group substitution is allowed
+ """
+ id = 'simple'
+
+ rules = [
+ ('/schema', dict(vid='schema')),
+ ('/index', dict(vid='index')),
+ ('/myprefs', dict(vid='epropertiesform')),
+ ('/siteconfig', dict(vid='systemepropertiesform')),
+ ('/manage', dict(vid='manage')),
+ ('/notfound', dict(vid='404')),
+ ('/error', dict(vid='error')),
+ (rgx('/schema/([^/]+?)/?'), dict(vid='eschema', rql=r'Any X WHERE X is EEType, X name "\1"')),
+ (rgx('/add/([^/]+?)/?'), dict(vid='creation', etype=r'\1')),
+ (rgx('/doc/images/(.+?)/?'), dict(vid='wdocimages', fid=r'\1')),
+ (rgx('/doc/?'), dict(vid='wdoc', fid=r'main')),
+ (rgx('/doc/(.+?)/?'), dict(vid='wdoc', fid=r'\1')),
+ (rgx('/changelog/?'), dict(vid='changelog')),
+ ]
+
+ def rewrite(self, req, uri):
+ """for each `input`, `output `in rules, if `uri` matches `input`,
+ req's form is updated with `output`
+ """
+ rset = None
+ for data in self.rules:
+ try:
+ inputurl, infos, required_groups = data
+ except ValueError:
+ inputurl, infos = data
+ required_groups = None
+ if required_groups and not req.user.matching_groups(required_groups):
+ continue
+ if isinstance(inputurl, basestring):
+ if inputurl == uri:
+ req.form.update(infos)
+ break
+ elif inputurl.match(uri): # it's a regexp
+ # XXX what about i18n ? (vtitle for instance)
+ for param, value in infos.items():
+ if isinstance(value, basestring):
+ req.form[param]= inputurl.sub(value, uri)
+ else:
+ req.form[param] = value
+ break
+ else:
+ self.debug("no simple rewrite rule found for %s", uri)
+ raise KeyError(uri)
+ return None, None
+
+
+def build_rset(rql, rgxgroups=None, cachekey=None, setuser=False,
+ vid=None, vtitle=None, form={}, **kwargs):
+
+ def do_build_rset(inputurl, uri, req, schema):
+ if rgxgroups:
+ match = inputurl.match(uri)
+ for arg, group in rgxgroups:
+ kwargs[arg] = match.group(group)
+ req.form.update(form)
+ if setuser:
+ kwargs['u'] = req.user.eid
+ if vid:
+ req.form['vid'] = vid
+ if vtitle:
+ req.form['vtitle'] = req._(vtitle) % kwargs
+ return None, req.execute(rql, kwargs, cachekey)
+ return do_build_rset
+
+def update_form(**kwargs):
+ def do_build_rset(inputurl, uri, req, schema):
+ match = inputurl.match(uri)
+ kwargs.update(match.groupdict())
+ req.form.update(kwargs)
+ return None, None
+ return do_build_rset
+
+def rgx_action(rql=None, args=None, cachekey=None, argsgroups=(), setuser=False,
+ form=None, formgroups=(), transforms={}, controller=None):
+ def do_build_rset(inputurl, uri, req, schema):
+ if rql:
+ kwargs = args and args.copy() or {}
+ if argsgroups:
+ match = inputurl.match(uri)
+ for key in argsgroups:
+ value = match.group(key)
+ try:
+ kwargs[key] = transforms[key](value)
+ except KeyError:
+ kwargs[key] = value
+ if setuser:
+ kwargs['u'] = req.user.eid
+ rset = req.execute(rql, kwargs, cachekey)
+ else:
+ rset = None
+ form2 = form and form.copy() or {}
+ if formgroups:
+ match = inputurl.match(uri)
+ for key in formgroups:
+ form2[key] = match.group(key)
+ if form2:
+ req.form.update(form2)
+ return controller, rset
+ return do_build_rset
+
+
+class SchemaBasedRewriter(URLRewriter):
+ """Here, the rules dict maps regexps or plain strings to
+ callbacks that will be called with (input, uri, req, schema)
+ """
+ id = 'schemabased'
+ rules = [
+ # rgxp : callback
+ (rgx('/search/(.+)'), build_rset(rql=r'Any X WHERE X has_text %(text)s',
+ rgxgroups=[('text', 1)])),
+ ]
+
+ def rewrite(self, req, uri):
+ # XXX this could be refacted with SimpleReqRewriter
+ for data in self.rules:
+ try:
+ inputurl, callback, required_groups = data
+ except ValueError:
+ inputurl, callback = data
+ required_groups = None
+ if required_groups and not req.user.matching_groups(required_groups):
+ continue
+ if isinstance(inputurl, basestring):
+ if inputurl == uri:
+ return callback(inputurl, uri, req, self.schema)
+ elif inputurl.match(uri): # it's a regexp
+ return callback(inputurl, uri, req, self.schema)
+ else:
+ self.debug("no schemabased rewrite rule found for %s", uri)
+ raise KeyError(uri)