handlers.py 文件源码

def qs_filter(cls, qs, flt, value, process_value=True):
        """
        Private method to set WHERE part of query.
        If required, Django-style filter is available via qs.filter()
        and peewee.DQ - this method provides joins.

        Filter relational operators are:
        * NOT - '-', not operator, should be user as prefix
        * < - 'lt', less than
        * > - 'gt', greater than
        * <= - 'lte', less than or equal
        * >= - 'gte', greater than or equal
        * != - 'ne', not equal
        * LIKE - 'like', classic like operator
        * ILIKE - 'ilike', case-insensitive like operator
        * IN - 'in', classic in. Values should be separated by comma
        * ISNULL - 'isnull', operator to know if smth is equal to null. Use -<fieldname>__isnull for IS NOT NULL
        """
        neg = False
        if flt[0] in '-':
            # Register NOT filter clause
            neg = True
            flt = flt[1:]
        fld_name, _, k = flt.rpartition('__')
        if not fld_name:
            # No underscore, simple filter
            fld_name, k = k, ''

        # Get filter
        op = FILTER_MAP.get(k, operator.eq)

        if neg:
            _op = op
            op = lambda f, x: operator.inv(_op(f, x))

        # Get field from model
        # raised AttributeError should be handled on higher level
        fld = getattr(cls.model_cls, fld_name)

        # Additional value processing
        if process_value:
            _v = value.decode()
            if isinstance(fld, peewee.BooleanField) and _v in ('0', 'f'):
                # Assume that '0' and 'f' are FALSE for boolean field
                _v = False
            elif k == 'in':
                # Force set parameter to list
                _v = _v.split(',')
            elif k == 'isnull':
                # ISNULL. Force set parameter to None
                _v = None
        else:
            _v = value

        # Send parameter to ORM
        return qs.where(op(fld, _v))