def delete_by_entity_id(self, *ids): if not ids: msg = 'There must be ids passed in to the delete method' raise AttributeError(msg) def _build_start(): pypher = Pypher() if self.start_entity.id is not None: qv = self.start_entity.query_variable where = __.ID(qv) == self.start_entity.id pypher.NODE(qv) self.wheres.append(where) else: pypher.NODE(self.start_query_variable) return pypher self.pypher = Pypher() self.matches.insert(0, self._build_end()) self.matches.insert(0, self._build_relationship()) self.matches.insert(0, _build_start()) self.pypher.MATCH for match in self.matches: self.pypher.append(match) id_params = [] for i in ids: key = 'end_id_{}'.format(i) id_params.append(Param(key, i)) self.wheres.append(__.ID(self.end_query_variable).IN(*id_params)) _id = __.ID(self.start_query_variable) if self.start_entity.id is not None: self.wheres.append(_id == self.start_entity.id) # else: # wheres.append(_id) self.pypher.WHERE.CAND(*self.wheres) self.pypher.DELETE(self.relationship_query_variable) self.reset() return str(self.pypher), self.pypher.bound_params
def _entity_by_id_builder(self, entity, id_val, add_labels=False): qv = entity.query_variable if not qv: qv = VM.set_query_var(entity) _id = VM.get_next(entity, 'id') _id = Param(_id, id_val) node_kwargs = {} if add_labels: node_kwargs['labels'] = entity.labels if isinstance(entity, Relationship): node = __.node(**node_kwargs).relationship(qv).node() else: node = __.node(qv, **node_kwargs) where = __.ID(qv) == _id self.matches.append(node) self.wheres.append(where) self.returns.append(entity.query_variable) return self
def _node_by_id(self, entity): qv = entity.query_variable if not qv: qv = VM.set_query_var(entity) _id = VM.get_next(entity, 'id') _id = Param(_id, entity.id) return __.node(qv).WHERE(__.ID(qv) == _id)
def delete_node(self, entity): _id = VM.get_next(entity, 'id') _id = Param(_id, entity.id) match = __.node(entity.query_variable) match.WHERE(__.ID(entity.query_variable) == _id) self.matches.append(match) self.deletes.append(entity.query_variable) return self
def delete_relationship(self, entity): _id = VM.get_next(entity, 'id') _id = Param(_id, entity.id) match = __.node() match.rel(entity.query_variable, labels=entity.labels) match.node() match.WHERE(__.ID(entity.query_variable) == _id) self.matches.append(match) self.deletes.append(entity.query_variable) return self
def _build_start(): pypher = Pypher() if self.start_entity.id is not None: qv = self.start_entity.query_variable where = __.ID(qv) == self.start_entity.id pypher.NODE(qv) self.wheres.append(where) else: pypher.NODE(self.start_query_variable) return pypher
def _build_start(self): pypher = Pypher() if self.start_entity.id: qv = self.start_entity.query_variable where = __.ID(qv) == self.start_entity.id pypher.NODE(qv) self.wheres.append(where) else: pypher.NODE(self.start_query_variable, labels=self.start_entity.labels) return pypher
def test_will_allow_binding_of_pypher_instances_as_values(self): p = Pypher() p.bind_param(__.ID('x'), 'SOME_ID') str(p) params = p.bound_params self.assertIn('SOME_ID', params) self.assertEqual('id(x)', params['SOME_ID']) self.assertEqual(1, len(params)) # do it in a Pypher string p = Pypher() val = 'some value {}'.format(random()) name = 'name' p.MATCH.node('p', 'person', lastname=__.coalesce(name, val)) cy = str(p) params = p.bound_params name = get_dict_key(params, 'name') val = get_dict_key(params, val) exp = 'MATCH (p:`person` {{`lastname`: coalesce(${name}, ${val})}})'.format( name=name, val=val) self.assertEqual(3, len(params)) self.assertEqual(exp, cy) # manually use Param and pass it in p = Pypher() val = 'some value {}'.format(random()) name = 'name' ln = Param(name, __.coalesce(name, val)) p.MATCH.node('p', 'person', lastname=ln) cy = str(p) params = p.bound_params name = get_dict_key(params, 'name') val = get_dict_key(params, val) exp = 'MATCH (p:`person` {{`lastname`: coalesce(${name}, ${val})}})'.format( name=name, val=val) self.assertEqual(3, len(params)) self.assertEqual(exp, cy)
def get_by_ids(self, entity, ids): p = Pypher() p.MATCH if isinstance(entity, Relationship): var = 'rel' p.node().rel(var, labels=entity.labels).node() else: var = 'node' p.node(var, labels=entity.labels) id_params = [] for i in ids: key = 'entity_id_{}'.format(i) id_params.append(Param(key, i)) p.WHERE.COR(__.ID(var).IN(*id_params)) p.RETURN(var) return str(p), p.bound_params
def entity_where(entity): if entity.id: wheres.append(__.ID(entity.query_variable) == entity.id)
def save_relationship(self, entity, ensure_unique=False): """this method handles creating and saving relationships. It will hanle quite a few situations. Given the structure: (start)-[rel]->[end] We can have: * A new start node * An existing start node * A new rel * An existing rel * A new end node * An existing end node Each start, rel, and end could have uniqueness assigned to it * start/end could have unique properties * rel could have unique relationships A Chyper query should be generated that looks something like this, depending on the settings for each of the nodes: MERGE (n_0:Node {`key`: val}) ON CREATE SET n_0.key = val, n_0.key2 = val2 ON MATCH SET n_0.key = val, n_0.key2 = val2 CREATE (n_0)-[r_0:RelLabel, {`key`: someVal}]->(n_1:Node {`key`: val}) RETURN n_0, n_1, r_0 """ start = entity.start start_properties = {} end = entity.end end_properties = {} props = self._properties(entity) if start is None or end is None: raise Exception('The relationship must have a start and end node') if not isinstance(start, Node): start = Node(id=start) if not isinstance(end, Node): end = Node(id=end) VM.set_query_var(start) VM.set_query_var(end) VM.set_query_var(entity) rel = Pypher() if start not in self.matched_entities: if start.id is not None: self._update_properties(start) self.matches.append(self._node_by_id(start)) else: start_properties = self._properties(start) self.matched_entities.append(start) self.returns.append(start.query_variable) if end not in self.matched_entities: if end.id is not None: self._update_properties(end) self.matches.append(self._node_by_id(end)) else: end_properties = self._properties(end) self.matched_entities.append(end) self.returns.append(end.query_variable) if entity.id is None: if start.id is not None: rel = rel.node(start.query_variable) else: start_query = Query(start, self.params) start_query.build_save_pypher() if len(start_query.creates): rel.append(*start_query.creates) elif len(start_query.merges): has_matches = len(self.matches) > 0 start_merge = Pypher() start_merge.MERGE(*start_query.merges) if start_query.on_create_sets: start_merge.OnCreateSet(*start_query.on_create_sets) if start_query.on_match_sets: start_merge.OnMatchSet(*start_query.on_match_sets) self.before_matches.append(start_merge) rel.node(start.query_variable) rel.rel(entity.query_variable, labels=entity.labels, direction='out', **props) if end.id is not None: rel.node(end.query_variable) else: end_query = Query(end, self.params) end_query.build_save_pypher() if len(end_query.creates): rel.append(*end_query.creates) elif len(end_query.merges): end_merge = Pypher().MERGE(*end_query.merges) if end_query.on_create_sets: end_merge.OnCreateSet(*end_query.on_create_sets) if end_query.on_match_sets: end_merge.OnMatchSet(*end_query.on_match_sets) self.before_matches.append(end_merge) rel.node(end.query_variable) if ensure_unique: self.merges.append(rel) else: self.creates.append(rel) else: _id = VM.get_next(entity, 'id') _id = Param(_id, entity.id) if start.id is not None: rel = rel.node(start.query_variable) else: start_query = Query(start, self.params) start_query.build_save_pypher() if len(start_query.creates): rel.append(*start_query.creates) elif len(start_query.merges): start_merge = Pypher().MERGE(*start_query.merges) if start_query.on_create_sets: start_merge.OnCreateSet(*start_query.on_create_sets) if start_query.on_match_sets: start_merge.OnMatchSet(*start_query.on_match_sets) if len(self.matches): self.matches[-1].append(start_merge) else: self.matches.append(start_merge) rel.node(start.query_variable) rel.rel(entity.query_variable, labels=entity.labels, direction='out') if end.id is not None: rel.node(end.query_variable) else: end_query = Query(end, self.params) end_query.build_save_pypher() if len(end_query.creates): rel.append(*end_query.creates) elif len(end_query.merges): end_merge = Pypher().MERGE(*end_query.merges) if end_query.on_create_sets: end_merge.OnCreateSet(*end_query.on_create_sets) if end_query.on_match_sets: end_merge.OnMatchSet(*end_query.on_match_sets) if len(self.matches): self.matches[-1].append(end_merge) else: self.matches.append(end_merge) rel.node(end.query_variable) rel.WHERE(__.ID(entity.query_variable) == _id) self._update_properties(entity) self.matches.append(rel) self.returns.append(entity.query_variable) return self