# copyright 2003-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb. If not, see <http://www.gnu.org/licenses/>.
"""a query processor to handle quick search shortcuts for cubicweb
"""
__docformat__ = "restructuredtext en"
import re
from logging import getLogger
from six import text_type
from yams.interfaces import IVocabularyConstraint
from rql import RQLSyntaxError, BadRQLQuery, parse
from rql.utils import rqlvar_maker
from rql.nodes import Relation
from cubicweb import Unauthorized
from cubicweb.view import Component
from cubicweb.web.views.ajaxcontroller import ajaxfunc
LOGGER = getLogger('cubicweb.magicsearch')
def _get_approriate_translation(translations_found, eschema):
"""return the first (should be the only one) possible translation according
to the given entity type
"""
# get the list of all attributes / relations for this kind of entity
existing_relations = set(eschema.subject_relations())
consistent_translations = translations_found & existing_relations
if len(consistent_translations) == 0:
return None
return consistent_translations.pop()
def translate_rql_tree(rqlst, translations, schema):
"""Try to translate each relation in the RQL syntax tree
:type rqlst: `rql.stmts.Statement`
:param rqlst: the RQL syntax tree
:type translations: dict
:param translations: the reverted l10n dict
:type schema: `cubicweb.schema.Schema`
:param schema: the instance's schema
"""
# var_types is used as a map : var_name / var_type
vartypes = {}
# ambiguous_nodes is used as a map : relation_node / (var_name, available_translations)
ambiguous_nodes = {}
# For each relation node, check if it's a localized relation name
# If it's a localized name, then use the original relation name, else
# keep the existing relation name
for relation in rqlst.get_nodes(Relation):
rtype = relation.r_type
lhs, rhs = relation.get_variable_parts()
if rtype == 'is':
try:
etype = translations[rhs.value]
rhs.value = etype
except KeyError:
# If no translation found, leave the entity type as is
etype = rhs.value
# Memorize variable's type
vartypes[lhs.name] = etype
else:
try:
translation_set = translations[rtype]
except KeyError:
pass # If no translation found, leave the relation type as is
else:
# Only one possible translation, no ambiguity
if len(translation_set) == 1:
relation.r_type = next(iter(translations[rtype]))
# More than 1 possible translation => resolve it later
else:
ambiguous_nodes[relation] = (lhs.name, translation_set)
if ambiguous_nodes:
resolve_ambiguities(vartypes, ambiguous_nodes, schema)
def resolve_ambiguities(var_types, ambiguous_nodes, schema):
"""Tries to resolve remaining ambiguities for translation
/!\ An ambiguity is when two different string can be localized with
the same string
A simple example:
- 'name' in a company context will be localized as 'nom' in French
- but ... 'surname' will also be localized as 'nom'
:type var_types: dict
:param var_types: a map : var_name / var_type
:type ambiguous_nodes: dict
:param ambiguous_nodes: a map : relation_node / (var_name, available_translations)
:type schema: `cubicweb.schema.Schema`
:param schema: the instance's schema
"""
# Now, try to resolve ambiguous translations
for relation, (var_name, translations_found) in ambiguous_nodes.items():
try:
vartype = var_types[var_name]
except KeyError:
continue
# Get schema for this entity type
eschema = schema.eschema(vartype)
rtype = _get_approriate_translation(translations_found, eschema)
if rtype is None:
continue
relation.r_type = rtype
QUOTED_SRE = re.compile(r'(.*?)(["\'])(.+?)\2')
TRANSLATION_MAPS = {}
def trmap(config, schema, lang):
try:
return TRANSLATION_MAPS[lang]
except KeyError:
assert lang in config.translations, '%s %s' % (lang, config.translations)
tr, ctxtr = config.translations[lang]
langmap = {}
for etype in schema.entities():
etype = str(etype)
langmap[tr(etype).capitalize()] = etype
langmap[etype.capitalize()] = etype
for rtype in schema.relations():
rtype = str(rtype)
langmap.setdefault(tr(rtype).lower(), set()).add(rtype)
langmap.setdefault(rtype, set()).add(rtype)
TRANSLATION_MAPS[lang] = langmap
return langmap
class BaseQueryProcessor(Component):
__abstract__ = True
__regid__ = 'magicsearch_processor'
# set something if you want explicit component search facility for the
# component
name = None
def process_query(self, uquery):
args = self.preprocess_query(uquery)
try:
return self._cw.execute(*args)
finally:
# rollback necessary to avoid leaving the connection in a bad state
self._cw.cnx.rollback()
def preprocess_query(self, uquery):
raise NotImplementedError()
class DoNotPreprocess(BaseQueryProcessor):
"""this one returns the raw query and should be placed in first position
of the chain
"""
name = 'rql'
priority = 0
def preprocess_query(self, uquery):
return uquery,
class QueryTranslator(BaseQueryProcessor):
""" parses through rql and translates into schema language entity names
and attributes
"""
priority = 2
def preprocess_query(self, uquery):
rqlst = parse(uquery, print_errors=False)
schema = self._cw.vreg.schema
# rql syntax tree will be modified in place if necessary
translate_rql_tree(rqlst, trmap(self._cw.vreg.config, schema, self._cw.lang),
schema)
return rqlst.as_string(),
class QSPreProcessor(BaseQueryProcessor):
"""Quick search preprocessor
preprocessing query in shortcut form to their RQL form
"""
priority = 4
def preprocess_query(self, uquery):
"""try to get rql from a unicode query string"""
args = None
try:
# Process as if there was a quoted part
args = self._quoted_words_query(uquery)
## No quoted part
except BadRQLQuery:
words = uquery.split()
if len(words) == 1:
args = self._one_word_query(*words)
elif len(words) == 2:
args = self._two_words_query(*words)
elif len(words) == 3:
args = self._three_words_query(*words)
else:
raise
return args
def _get_entity_type(self, word):
"""check if the given word is matching an entity type, return it if
it's the case or raise BadRQLQuery if not
"""
etype = word.capitalize()
try:
return trmap(self._cw.vreg.config, self._cw.vreg.schema, self._cw.lang)[etype]
except KeyError:
raise BadRQLQuery('%s is not a valid entity name' % etype)
def _get_attribute_name(self, word, eschema):
"""check if the given word is matching an attribute of the given entity type,
return it normalized if found or return it untransformed else
"""
"""Returns the attributes's name as stored in the DB"""
# Need to convert from unicode to string (could be whatever)
rtype = word.lower()
# Find the entity name as stored in the DB
translations = trmap(self._cw.vreg.config, self._cw.vreg.schema, self._cw.lang)
try:
translations = translations[rtype]
except KeyError:
raise BadRQLQuery('%s is not a valid attribute for %s entity type'
% (word, eschema))
rtype = _get_approriate_translation(translations, eschema)
if rtype is None:
raise BadRQLQuery('%s is not a valid attribute for %s entity type'
% (word, eschema))
return rtype
def _one_word_query(self, word):
"""Specific process for one word query (case (1) of preprocess_rql)
"""
# if this is an integer, then directly go to eid
try:
eid = int(word)
return 'Any X WHERE X eid %(x)s', {'x': eid}, 'x'
except ValueError:
etype = self._get_entity_type(word)
return '%s %s' % (etype, etype[0]),
def _complete_rql(self, searchstr, etype, rtype=None, var=None, searchattr=None):
searchop = ''
if '%' in searchstr:
if rtype:
possible_etypes = self._cw.vreg.schema.rschema(rtype).objects(etype)
else:
possible_etypes = [self._cw.vreg.schema.eschema(etype)]
if searchattr or len(possible_etypes) == 1:
searchattr = searchattr or possible_etypes[0].main_attribute()
searchop = 'LIKE '
searchattr = searchattr or 'has_text'
if var is None:
var = etype[0]
return '%s %s %s%%(text)s' % (var, searchattr, searchop)
def _two_words_query(self, word1, word2):
"""Specific process for two words query (case (2) of preprocess_rql)
"""
etype = self._get_entity_type(word1)
# this is a valid RQL query : ("Person X", or "Person TMP1")
if len(word2) == 1 and word2.isupper():
return '%s %s' % (etype, word2),
# else, suppose it's a shortcut like : Person Smith
restriction = self._complete_rql(word2, etype)
if ' has_text ' in restriction:
rql = '%s %s ORDERBY FTIRANK(%s) DESC WHERE %s' % (
etype, etype[0], etype[0], restriction)
else:
rql = '%s %s WHERE %s' % (
etype, etype[0], restriction)
return rql, {'text': word2}
def _three_words_query(self, word1, word2, word3):
"""Specific process for three words query (case (3) of preprocess_rql)
"""
etype = self._get_entity_type(word1)
eschema = self._cw.vreg.schema.eschema(etype)
rtype = self._get_attribute_name(word2, eschema)
# expand shortcut if rtype is a non final relation
if not self._cw.vreg.schema.rschema(rtype).final:
return self._expand_shortcut(etype, rtype, word3)
if '%' in word3:
searchop = 'LIKE '
else:
searchop = ''
rql = '%s %s WHERE %s' % (etype, etype[0],
self._complete_rql(word3, etype, searchattr=rtype))
return rql, {'text': word3}
def _expand_shortcut(self, etype, rtype, searchstr):
"""Expands shortcut queries on a non final relation to use has_text or
the main attribute (according to possible entity type) if '%' is used in the
search word
Transforms : 'person worksat IBM' into
'Personne P WHERE P worksAt C, C has_text "IBM"'
"""
# check out all possilbe entity types for the relation represented
# by 'rtype'
mainvar = etype[0]
searchvar = mainvar + '1'
restriction = self._complete_rql(searchstr, etype, rtype=rtype,
var=searchvar)
if ' has_text ' in restriction:
rql = ('%s %s ORDERBY FTIRANK(%s) DESC '
'WHERE %s %s %s, %s' % (etype, mainvar, searchvar,
mainvar, rtype, searchvar, # P worksAt C
restriction))
else:
rql = ('%s %s WHERE %s %s %s, %s' % (etype, mainvar,
mainvar, rtype, searchvar, # P worksAt C
restriction))
return rql, {'text': searchstr}
def _quoted_words_query(self, ori_rql):
"""Specific process when there's a "quoted" part
"""
m = QUOTED_SRE.match(ori_rql)
# if there's no quoted part, then no special pre-processing to do
if m is None:
raise BadRQLQuery("unable to handle request %r" % ori_rql)
left_words = m.group(1).split()
quoted_part = m.group(3)
# Case (1) : Company "My own company"
if len(left_words) == 1:
try:
word1 = left_words[0]
return self._two_words_query(word1, quoted_part)
except BadRQLQuery as error:
raise BadRQLQuery("unable to handle request %r" % ori_rql)
# Case (2) : Company name "My own company";
elif len(left_words) == 2:
word1, word2 = left_words
return self._three_words_query(word1, word2, quoted_part)
# return ori_rql
raise BadRQLQuery("unable to handle request %r" % ori_rql)
class FullTextTranslator(BaseQueryProcessor):
priority = 10
name = 'text'
def preprocess_query(self, uquery):
"""suppose it's a plain text query"""
return 'Any X ORDERBY FTIRANK(X) DESC WHERE X has_text %(text)s', {'text': uquery}
class MagicSearchComponent(Component):
__regid__ = 'magicsearch'
def __init__(self, req, rset=None):
super(MagicSearchComponent, self).__init__(req, rset=rset)
processors = []
self.by_name = {}
for processorcls in self._cw.vreg['components']['magicsearch_processor']:
# instantiation needed
processor = processorcls(self._cw)
processors.append(processor)
if processor.name is not None:
assert not processor.name in self.by_name
self.by_name[processor.name.lower()] = processor
self.processors = sorted(processors, key=lambda x: x.priority)
def process_query(self, uquery):
assert isinstance(uquery, text_type)
try:
procname, query = uquery.split(':', 1)
proc = self.by_name[procname.strip().lower()]
uquery = query.strip()
except Exception:
# use processor chain
unauthorized = None
for proc in self.processors:
try:
return proc.process_query(uquery)
# FIXME : we don't want to catch any exception type here !
except (RQLSyntaxError, BadRQLQuery):
pass
except Unauthorized as ex:
unauthorized = ex
continue
except Exception as ex:
LOGGER.debug('%s: %s', ex.__class__.__name__, ex)
continue
if unauthorized:
raise unauthorized
else:
# explicitly specified processor: don't try to catch the exception
return proc.process_query(uquery)
raise BadRQLQuery(self._cw._('sorry, the server is unable to handle this query'))
## RQL suggestions builder ####################################################
class RQLSuggestionsBuilder(Component):
"""main entry point is `build_suggestions()` which takes
an incomplete RQL query and returns a list of suggestions to complete
the query.
This component is enabled by default and is used to provide autocompletion
in the RQL search bar. If you don't want this feature in your application,
just unregister it or make it unselectable.
.. automethod:: cubicweb.web.views.magicsearch.RQLSuggestionsBuilder.build_suggestions
.. automethod:: cubicweb.web.views.magicsearch.RQLSuggestionsBuilder.etypes_suggestion_set
.. automethod:: cubicweb.web.views.magicsearch.RQLSuggestionsBuilder.possible_etypes
.. automethod:: cubicweb.web.views.magicsearch.RQLSuggestionsBuilder.possible_relations
.. automethod:: cubicweb.web.views.magicsearch.RQLSuggestionsBuilder.vocabulary
"""
__regid__ = 'rql.suggestions'
#: maximum number of results to fetch when suggesting attribute values
attr_value_limit = 20
def build_suggestions(self, user_rql):
"""return a list of suggestions to complete `user_rql`
:param user_rql: an incomplete RQL query
"""
req = self._cw
try:
if 'WHERE' not in user_rql: # don't try to complete if there's no restriction
return []
variables, restrictions = [part.strip() for part in user_rql.split('WHERE', 1)]
if ',' in restrictions:
restrictions, incomplete_part = restrictions.rsplit(',', 1)
user_rql = '%s WHERE %s' % (variables, restrictions)
else:
restrictions, incomplete_part = '', restrictions
user_rql = variables
select = parse(user_rql, print_errors=False).children[0]
req.vreg.rqlhelper.annotate(select)
req.vreg.solutions(req, select, {})
if restrictions:
return ['%s, %s' % (user_rql, suggestion)
for suggestion in self.rql_build_suggestions(select, incomplete_part)]
else:
return ['%s WHERE %s' % (user_rql, suggestion)
for suggestion in self.rql_build_suggestions(select, incomplete_part)]
except Exception as exc: # we never want to crash
self.debug('failed to build suggestions: %s', exc)
return []
## actual completion entry points #########################################
def rql_build_suggestions(self, select, incomplete_part):
"""
:param select: the annotated select node (rql syntax tree)
:param incomplete_part: the part of the rql query that needs
to be completed, (e.g. ``X is Pr``, ``X re``)
"""
chunks = incomplete_part.split(None, 2)
if not chunks: # nothing to complete
return []
if len(chunks) == 1: # `incomplete` looks like "MYVAR"
return self._complete_rqlvar(select, *chunks)
elif len(chunks) == 2: # `incomplete` looks like "MYVAR some_rel"
return self._complete_rqlvar_and_rtype(select, *chunks)
elif len(chunks) == 3: # `incomplete` looks like "MYVAR some_rel something"
return self._complete_relation_object(select, *chunks)
else: # would be anything else, hard to decide what to do here
return []
# _complete_* methods are considered private, at least while the API
# isn't stabilized.
def _complete_rqlvar(self, select, rql_var):
"""return suggestions for "variable only" incomplete_part
as in :
- Any X WHERE X
- Any X WHERE X is Project, Y
- etc.
"""
return ['%s %s %s' % (rql_var, rtype, dest_var)
for rtype, dest_var in self.possible_relations(select, rql_var)]
def _complete_rqlvar_and_rtype(self, select, rql_var, user_rtype):
"""return suggestions for "variable + rtype" incomplete_part
as in :
- Any X WHERE X is
- Any X WHERE X is Person, X firstn
- etc.
"""
# special case `user_type` == 'is', return every possible type.
if user_rtype == 'is':
return self._complete_is_relation(select, rql_var)
else:
return ['%s %s %s' % (rql_var, rtype, dest_var)
for rtype, dest_var in self.possible_relations(select, rql_var)
if rtype.startswith(user_rtype)]
def _complete_relation_object(self, select, rql_var, user_rtype, user_value):
"""return suggestions for "variable + rtype + some_incomplete_value"
as in :
- Any X WHERE X is Per
- Any X WHERE X is Person, X firstname "
- Any X WHERE X is Person, X firstname "Pa
- etc.
"""
# special case `user_type` == 'is', return every possible type.
if user_rtype == 'is':
return self._complete_is_relation(select, rql_var, user_value)
elif user_value:
if user_value[0] in ('"', "'"):
# if finished string, don't suggest anything
if len(user_value) > 1 and user_value[-1] == user_value[0]:
return []
user_value = user_value[1:]
return ['%s %s "%s"' % (rql_var, user_rtype, value)
for value in self.vocabulary(select, rql_var,
user_rtype, user_value)]
return []
def _complete_is_relation(self, select, rql_var, prefix=''):
"""return every possible types for rql_var
:param prefix: if specified, will only return entity types starting
with the specified value.
"""
return ['%s is %s' % (rql_var, etype)
for etype in self.possible_etypes(select, rql_var, prefix)]
def etypes_suggestion_set(self):
"""returns the list of possible entity types to suggest
The default is to return any non-final entity type available
in the schema.
Can be overridden for instance if an application decides
to restrict this list to a meaningful set of business etypes.
"""
schema = self._cw.vreg.schema
return set(eschema.type for eschema in schema.entities() if not eschema.final)
def possible_etypes(self, select, rql_var, prefix=''):
"""return all possible etypes for `rql_var`
The returned list will always be a subset of meth:`etypes_suggestion_set`
:param select: the annotated select node (rql syntax tree)
:param rql_var: the variable name for which we want to know possible types
:param prefix: if specified, will only return etypes starting with it
"""
available_etypes = self.etypes_suggestion_set()
possible_etypes = set()
for sol in select.solutions:
if rql_var in sol and sol[rql_var] in available_etypes:
possible_etypes.add(sol[rql_var])
if not possible_etypes:
# `Any X WHERE X is Person, Y is`
# -> won't have a solution, need to give all etypes
possible_etypes = available_etypes
return sorted(etype for etype in possible_etypes if etype.startswith(prefix))
def possible_relations(self, select, rql_var, include_meta=False):
"""returns a list of couple (rtype, dest_var) for each possible
relations with `rql_var` as subject.
``dest_var`` will be picked among availabel variables if types match,
otherwise a new one will be created.
"""
schema = self._cw.vreg.schema
relations = set()
untyped_dest_var = next(rqlvar_maker(defined=select.defined_vars))
# for each solution
# 1. find each possible relation
# 2. for each relation:
# 2.1. if the relation is meta, skip it
# 2.2. for each possible destination type, pick up possible
# variables for this type or use a new one
for sol in select.solutions:
etype = sol[rql_var]
sol_by_types = {}
for varname, var_etype in sol.items():
# don't push subject var to avoid "X relation X" suggestion
if varname != rql_var:
sol_by_types.setdefault(var_etype, []).append(varname)
for rschema in schema[etype].subject_relations():
if include_meta or not rschema.meta:
for dest in rschema.objects(etype):
for varname in sol_by_types.get(dest.type, (untyped_dest_var,)):
suggestion = (rschema.type, varname)
if suggestion not in relations:
relations.add(suggestion)
return sorted(relations)
def vocabulary(self, select, rql_var, user_rtype, rtype_incomplete_value):
"""return acceptable vocabulary for `rql_var` + `user_rtype` in `select`
Vocabulary is either found from schema (Yams) definition or
directly from database.
"""
schema = self._cw.vreg.schema
vocab = []
for sol in select.solutions:
# for each solution :
# - If a vocabulary constraint exists on `rql_var+user_rtype`, use it
# to define possible values
# - Otherwise, query the database to fetch available values from
# database (limiting results to `self.attr_value_limit`)
try:
eschema = schema.eschema(sol[rql_var])
rdef = eschema.rdef(user_rtype)
except KeyError: # unknown relation
continue
cstr = rdef.constraint_by_interface(IVocabularyConstraint)
if cstr is not None:
# a vocabulary is found, use it
vocab += [value for value in cstr.vocabulary()
if value.startswith(rtype_incomplete_value)]
elif rdef.final:
# no vocab, query database to find possible value
vocab_rql = 'DISTINCT Any V LIMIT %s WHERE X is %s, X %s V' % (
self.attr_value_limit, eschema.type, user_rtype)
vocab_kwargs = {}
if rtype_incomplete_value:
vocab_rql += ', X %s LIKE %%(value)s' % user_rtype
vocab_kwargs['value'] = u'%s%%' % rtype_incomplete_value
vocab += [value for value, in
self._cw.execute(vocab_rql, vocab_kwargs)]
return sorted(set(vocab))
@ajaxfunc(output_type='json')
def rql_suggest(self):
rql_builder = self._cw.vreg['components'].select_or_none('rql.suggestions', self._cw)
if rql_builder:
return rql_builder.build_suggestions(self._cw.form['term'])
return []