Ejemplo n.º 1
0
    def __init__(self, q_arr, param_set={}):
        """
        @param q_arr: cypher query as an array, the string is ' '.join(q_str_or_array)
        is used to convert it to string type
        """
        assert type(q_arr) is list

        # establish query type
        self.q_str = ' '.join(q_arr)  # FIXME: rm
        self.pt_root = Cypher_Parser().parse_expression(self.q_str)
        self.param_set = param_set
Ejemplo n.º 2
0
    def __init__(self, q_arr, param_set={}):
        """
        @param q_str_or_array: cypher query to add - if passed as an array ' '.join(q_str_or_array)
        is used to convert it to string type
        """
        assert type(q_arr) is list

        # establish query type
        self.q_str = ' '.join(q_arr)  # FIXME: rm
        self.pt_root = Cypher_Parser().parse_expression(self.q_str)
        self.param_set = param_set
Ejemplo n.º 3
0
class DB_Query(object):
    """
    DB query object
    """
    def __init__(self, q_arr, param_set={}):
        """
        @param q_arr: cypher query as an array, the string is ' '.join(q_str_or_array)
        is used to convert it to string type
        """
        assert type(q_arr) is list

        # establish query type
        self.q_str = ' '.join(q_arr)  # FIXME: rm
        self.pt_root = Cypher_Parser().parse_expression(self.q_str)
        self.param_set = param_set

    def __str__(self):
        return self.pt_root.str__cypher_query()

    def __repr__(self):
        return 'q: %s, params: %s\n%s' % (self.pt_root.str__cypher_query(),
                                          self.param_set,
                                          self.pt_root.str__struct_tree())

    def __iter__(self):
        for keyword, clause_set in self.pt_root.index__kw_to_clause_set(
        ).items():
            yield keyword, clause_set

    def t__add_node_filter__meta_label(self):

        if Query_Struct_Type.w == self.query_struct_type:
            return

        meta_label_cond = '0 = length(filter(_lbl in labels(n) where _lbl in {meta_label_set}))'  # filter nodes with meta labels

        c_set__where = self.pt_root.clause_set_by_kw('where')

        if not c_set__where:
            c_set__match = self.pt_root.clause_set_by_kw('match')

            first_match_clause = c_set__match.pop()
            wc = first_match_clause.spawn_sibling__adjacent(e_clause__where)
            wc.spawn_child(e_keyword, 'where')
            wc.spawn_child(e_value).value = meta_label_cond
        else:  # where clause present
            assert len(
                c_set__where
            ) == 1, 't__add_node_filter__meta_label: no support for multi-where clauses query transformation'
            wc = c_set__where[0]
            wc_cond = wc.condition_value
            wc.set_condition(meta_label_cond + ' and ' + wc_cond)

        self.param_set['meta_label_set'] = neo4j_schema.meta_label_set

    @property
    def query_struct_type(self):
        """
        calc query_structure_type: read|write|read-write
        """
        r = False
        w = False
        for kw, _clause_set in self.pt_root.index__kw_to_clause_set().items():
            if kw in neo4j_cypher_parser.tok_set__kw__write:
                w = True
            if kw == 'match':
                r = True

        if r and w: return Query_Struct_Type.rw
        if r and not w: return Query_Struct_Type.r
        if w and not r: return Query_Struct_Type.w
        return Query_Struct_Type.unknown

    def str__cypher_query(self):
        return self.pt_root.str__cypher_query()
Ejemplo n.º 4
0
class DB_Query(object):
    """
    DB query object
    """

    def __init__(self, q_arr, param_set={}):
        """
        @param q_str_or_array: cypher query to add - if passed as an array ' '.join(q_str_or_array)
        is used to convert it to string type
        """
        assert type(q_arr) is list

        # establish query type
        self.q_str = ' '.join(q_arr)  # FIXME: rm
        self.pt_root = Cypher_Parser().parse_expression(self.q_str)
        self.param_set = param_set

    def __str__(self):
        return self.pt_root.str__cypher_query()

    def __repr__(self):
        return 'q: %s, params: %s\n%s' % (self.pt_root.str__cypher_query(),
                                          self.param_set,
                                          self.pt_root.str__struct_tree())

    def __iter__(self):
        for keyword, clause_set in self.pt_root.index__kw_to_clause_set().items():
            yield keyword, clause_set

    def t__add_node_filter__meta_label(self):

        if Query_Struct_Type.w == self.query_struct_type:
            return

        meta_label_cond = '0 = length(filter(_lbl in labels(n) where _lbl in {meta_label_set}))'  # filter nodes with meta labels

        c_set__where = self.pt_root.clause_set_by_kw('where')

        if not c_set__where:
            c_set__match = self.pt_root.clause_set_by_kw('match')

            first_match_clause = c_set__match.pop()
            wc = first_match_clause.spawn_sibling__adjacent(e_clause__where)
            wc.spawn_child(e_keyword, 'where')
            wc.spawn_child(e_value).value = meta_label_cond
        else:  # where clause present
            assert len(c_set__where) == 1, 't__add_node_filter__meta_label: no support for multi-where clauses query transformation'
            wc = c_set__where[0]
            wc_cond = wc.condition_value
            wc.set_condition(meta_label_cond + ' and ' + wc_cond)

        self.param_set['meta_label_set'] = neo4j_schema.meta_label_set

    @property
    def query_struct_type(self):
        """
        calc query_structure_type: read|write|read-write
        """
        r = False
        w = False
        for kw, _clause_set in self.pt_root.index__kw_to_clause_set().items():
            if kw in neo4j_cypher_parser.tok_set__kw__write:
                w = True
            if kw == 'match':
                r = True

        if r and w: return Query_Struct_Type.rw
        if r and not w: return Query_Struct_Type.r
        if w and not r: return Query_Struct_Type.w
        return Query_Struct_Type.unknown

    def str__cypher_query(self):
        return self.pt_root.str__cypher_query()