+
−"""Rules based url rewriter component, to get configurable RESTful urls
+
−
+
−:organization: Logilab
+
−:copyright: 2007-2009 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.
+
−:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
+
−:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses
+
−"""
+
−import re
+
−
+
−from cubicweb import typed_eid
+
−from cubicweb.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(type):
+
−    """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'
+
−    __abstract__ = True
+
−    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
+
−    """
+
−    __regid__ = 'simple'
+
−
+
−    rules = [
+
−        ('/_', dict(vid='manage')),
+
−        ('/_registry', dict(vid='registry')),
+
−#        (rgx('/_([^/]+?)/?'), dict(vid=r'\1')),
+
−        ('/schema',  dict(vid='schema')),
+
−        ('/index', dict(vid='index')),
+
−        ('/myprefs', dict(vid='propertiesform')),
+
−        ('/siteconfig', dict(vid='systempropertiesform')),
+
−        ('/siteinfo', dict(vid='info')),
+
−        ('/manage', dict(vid='manage')),
+
−        ('/notfound', dict(vid='404')),
+
−        ('/error', dict(vid='error')),
+
−        ('/sparql', dict(vid='sparql')),
+
−        (rgx('/schema/([^/]+?)/?'),  dict(vid='eschema', rql=r'Any X WHERE X is CWEType, 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`
+
−        """
+
−        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,
+
−                      cachekey=cachekey # necessary to avoid UnboundLocalError
+
−                      ):
+
−        if rql:
+
−            kwargs = args and args.copy() or {}
+
−            if argsgroups:
+
−                if cachekey is not None and isinstance(cachekey, basestring):
+
−                    cachekey = (cachekey,)
+
−                match = inputurl.match(uri)
+
−                for key in argsgroups:
+
−                    value = match.group(key)
+
−                    try:
+
−                        kwargs[key] = transforms[key](value)
+
−                    except KeyError:
+
−                        kwargs[key] = value
+
−                    if cachekey is not None and key in cachekey:
+
−                        kwargs[key] = typed_eid(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 "vtitle" in form2:
+
−            form2['vtitle'] = req.__(form2['vtitle'])
+
−        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)
+
−    """
+
−    __regid__ = '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._cw.vreg.schema)
+
−            elif inputurl.match(uri): # it's a regexp
+
−                return callback(inputurl, uri, req, self._cw.vreg.schema)
+
−        else:
+
−            self.debug("no schemabased rewrite rule found for %s", uri)
+
−            raise KeyError(uri)