Homec4science
Diffusion invenio-infoscience (iugw2017) Browse

R3600/invenio/modules/search/jsonext/parsers/aggregation_parser.py
53063323045fiugw2017

Last Change
Raw File

aggregation_parser.py
View Options

# -*- coding: utf-8 -*-
#
# This file is part of Invenio.
# Copyright (C) 2015 CERN.
#
# Invenio is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of the
# License, or (at your option) any later version.
#
# Invenio 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
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Invenio; if not, write to the Free Software Foundation, Inc.,
# 60 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
"""Aggregation parser extension."""
from pyparsing import Suppress, OneOrMore, Word, alphanums, nestedExpr, \
originalTextFor, Keyword
from invenio.modules.jsonalchemy.parser import FieldBaseExtensionParser, \
FieldParser, PYTHON_ALLOWED_EXPR, indentedBlock
class AggregationParser(FieldBaseExtensionParser):
"""Handles the aggregation section from a field definition.
An example of this section could be::
title:
aggregation:
title(), {'<aggregation_type>': '<aggregagtion_body>'}
authors:
aggregation:
author('native'), {....}
author('elasticsearch'), {....}
The parameter passed to the aggregation could be used by the aggregation
for example to decide if the current aggregation rule will be applied
depending on the search engine.
"""
__parsername__ = 'aggregation'
@classmethod
def parse_element(cls, indent_stack):
"""Set to the rule the list of aggregations."""
aggregation_body = (
Word(alphanums + "_") +
originalTextFor(nestedExpr()) +
Suppress(',') +
PYTHON_ALLOWED_EXPR
).setParseAction(lambda toks: {
'name': toks[0],
'engine': eval(toks[1]),
'rule': eval(toks[2])
})
return (Keyword('aggregation:').suppress() +
indentedBlock(OneOrMore(aggregation_body), indent_stack)
).setResultsName('aggregation')
@classmethod
def create_element(cls, rule, namespace):
"""Prepare the list of aggregations with their names and parameters."""
id_ = rule.field['json_id']
aggregations = {} if not rule.extend else \
FieldParser.field_definitions(namespace)[id_].get(
'aggregation', {})
for aggregation in rule.aggregation:
if aggregation['name'] not in aggregations:
aggregations[aggregation['name']] = []
aggregations[aggregation['name']].append((
aggregation['engine'], aggregation['rule']))
return aggregations
parser = AggregationParser
c4science · Help