--- a/rqlrewrite.py Fri Jul 12 10:39:01 2013 +0200
+++ b/rqlrewrite.py Mon Jul 15 10:59:34 2013 +0200
@@ -1,4 +1,4 @@
-# copyright 2003-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+# copyright 2003-2013 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
@@ -33,6 +33,13 @@
from cubicweb import Unauthorized
+def cleanup_solutions(rqlst, solutions):
+ for sol in solutions:
+ for vname in list(sol):
+ if not (vname in rqlst.defined_vars or vname in rqlst.aliases):
+ del sol[vname]
+
+
def add_types_restriction(schema, rqlst, newroot=None, solutions=None):
if newroot is None:
assert solutions is None
@@ -132,10 +139,35 @@
return newsolutions
+def _add_noinvariant(noinvariant, restricted, select, nbtrees):
+ # a variable can actually be invariant if it has not been restricted for
+ # security reason or if security assertion hasn't modified the possible
+ # solutions for the query
+ for vname in restricted:
+ try:
+ var = select.defined_vars[vname]
+ except KeyError:
+ # this is an alias
+ continue
+ if nbtrees != 1 or len(var.stinfo['possibletypes']) != 1:
+ noinvariant.add(var)
+
+
+def _expand_selection(terms, selected, aliases, select, newselect):
+ for term in terms:
+ for vref in term.iget_nodes(n.VariableRef):
+ if not vref.name in selected:
+ select.append_selected(vref)
+ colalias = newselect.get_variable(vref.name, len(aliases))
+ aliases.append(n.VariableRef(colalias))
+ selected.add(vref.name)
+
+
def iter_relations(stinfo):
# this is a function so that test may return relation in a predictable order
return stinfo['relations'] - stinfo['rhsrelations']
+
class Unsupported(Exception):
"""raised when an rql expression can't be inserted in some rql query
because it create an unresolvable query (eg no solutions found)
@@ -164,6 +196,110 @@
if len(self.select.solutions) < len(self.solutions):
raise Unsupported()
+ def insert_local_checks(self, select, kwargs,
+ localchecks, restricted, noinvariant):
+ """
+ select: the rql syntax tree Select node
+ kwargs: query arguments
+
+ localchecks: {(('Var name', (rqlexpr1, rqlexpr2)),
+ ('Var name1', (rqlexpr1, rqlexpr23))): [solution]}
+
+ (see querier._check_permissions docstring for more information)
+
+ restricted: set of variable names to which an rql expression has to be
+ applied
+
+ noinvariant: set of variable names that can't be considered has
+ invariant due to security reason (will be filed by this method)
+ """
+ nbtrees = len(localchecks)
+ myunion = union = select.parent
+ # transform in subquery when len(localchecks)>1 and groups
+ if nbtrees > 1 and (select.orderby or select.groupby or
+ select.having or select.has_aggregat or
+ select.distinct or
+ select.limit or select.offset):
+ newselect = stmts.Select()
+ # only select variables in subqueries
+ origselection = select.selection
+ select.select_only_variables()
+ select.has_aggregat = False
+ # create subquery first so correct node are used on copy
+ # (eg ColumnAlias instead of Variable)
+ aliases = [n.VariableRef(newselect.get_variable(vref.name, i))
+ for i, vref in enumerate(select.selection)]
+ selected = set(vref.name for vref in aliases)
+ # now copy original selection and groups
+ for term in origselection:
+ newselect.append_selected(term.copy(newselect))
+ if select.orderby:
+ sortterms = []
+ for sortterm in select.orderby:
+ sortterms.append(sortterm.copy(newselect))
+ for fnode in sortterm.get_nodes(n.Function):
+ if fnode.name == 'FTIRANK':
+ # we've to fetch the has_text relation as well
+ var = fnode.children[0].variable
+ rel = iter(var.stinfo['ftirels']).next()
+ assert not rel.ored(), 'unsupported'
+ newselect.add_restriction(rel.copy(newselect))
+ # remove relation from the orig select and
+ # cleanup variable stinfo
+ rel.parent.remove(rel)
+ var.stinfo['ftirels'].remove(rel)
+ var.stinfo['relations'].remove(rel)
+ # XXX not properly re-annotated after security insertion?
+ newvar = newselect.get_variable(var.name)
+ newvar.stinfo.setdefault('ftirels', set()).add(rel)
+ newvar.stinfo.setdefault('relations', set()).add(rel)
+ newselect.set_orderby(sortterms)
+ _expand_selection(select.orderby, selected, aliases, select, newselect)
+ select.orderby = () # XXX dereference?
+ if select.groupby:
+ newselect.set_groupby([g.copy(newselect) for g in select.groupby])
+ _expand_selection(select.groupby, selected, aliases, select, newselect)
+ select.groupby = () # XXX dereference?
+ if select.having:
+ newselect.set_having([g.copy(newselect) for g in select.having])
+ _expand_selection(select.having, selected, aliases, select, newselect)
+ select.having = () # XXX dereference?
+ if select.limit:
+ newselect.limit = select.limit
+ select.limit = None
+ if select.offset:
+ newselect.offset = select.offset
+ select.offset = 0
+ myunion = stmts.Union()
+ newselect.set_with([n.SubQuery(aliases, myunion)], check=False)
+ newselect.distinct = select.distinct
+ solutions = [sol.copy() for sol in select.solutions]
+ cleanup_solutions(newselect, solutions)
+ newselect.set_possible_types(solutions)
+ # if some solutions doesn't need rewriting, insert original
+ # select as first union subquery
+ if () in localchecks:
+ myunion.append(select)
+ # we're done, replace original select by the new select with
+ # subqueries (more added in the loop below)
+ union.replace(select, newselect)
+ elif not () in localchecks:
+ union.remove(select)
+ for lcheckdef, lchecksolutions in localchecks.iteritems():
+ if not lcheckdef:
+ continue
+ myrqlst = select.copy(solutions=lchecksolutions)
+ myunion.append(myrqlst)
+ # in-place rewrite + annotation / simplification
+ lcheckdef = [({var: 'X'}, rqlexprs) for var, rqlexprs in lcheckdef]
+ self.rewrite(myrqlst, lcheckdef, lchecksolutions, kwargs)
+ _add_noinvariant(noinvariant, restricted, myrqlst, nbtrees)
+ if () in localchecks:
+ select.set_possible_types(localchecks[()])
+ add_types_restriction(self.schema, select)
+ _add_noinvariant(noinvariant, restricted, select, nbtrees)
+ self.annotate(union)
+
def rewrite(self, select, snippets, solutions, kwargs, existingvars=None):
"""
snippets: (varmap, list of rql expression)