Source code for asclepias_broker.search.query

# -*- coding: utf-8 -*-
#
# Copyright (C) 2018 CERN.
#
# Asclepias Broker is free software; you can redistribute it and/or modify it
# under the terms of the MIT License; see LICENSE file for more details.
"""Search utilities."""

from typing import Dict, Sized

from elasticsearch_dsl import Q
from elasticsearch_dsl.query import Range
from flask import request
from invenio_records_rest.errors import InvalidQueryRESTError
from invenio_rest.errors import FieldError, RESTValidationError
import json

def search_factory(self, search, query_parser=None):
    """Parse query using elasticsearch DSL query.

    :param self: REST view.
    :param search: Elastic search DSL search instance.
    :returns: Tuple with search instance and URL arguments.
    """
    from invenio_records_rest.facets import default_facets_factory
    from invenio_records_rest.sorter import default_sorter_factory
    search_index = search._index[0]

    # TODO: make "scheme" optional?
    for field in ('id', 'scheme', 'relation'):
        if field not in request.values:
            raise RESTValidationError(
                errors=[FieldError(field, 'Required field.')])

    search, urlkwargs = default_facets_factory(search, search_index)
    search, sortkwargs = default_sorter_factory(search, search_index)
    for key, value in sortkwargs.items():
        urlkwargs.add(key, value)

    # Apply 'identity' grouping by default
    if 'group_by' not in request.values:
        search = search.filter(Q('term', Grouping='identity'))
        urlkwargs['group_by'] = 'identity'

    try:
        query_string = request.values.get('q')
        if query_string:
            search = search.query(Q('query_string', query=query_string,
                                    default_field='_search_all'))
            urlkwargs['q'] = query_string
    except SyntaxError:
        raise InvalidQueryRESTError()

    # Exclude the identifiers by which the search was made (large aggregate)
    search = search.source(exclude=['*.SearchIdentifier'])
    return search, urlkwargs

def meta_search_factory(self, search, query_parser=None):
    """Parse query using elasticsearch DSL query.

    :param self: REST view.
    :param search: Elastic search DSL search instance.
    :returns: Tuple with search instance and URL arguments.
    """
    from invenio_records_rest.facets import default_facets_factory
    from invenio_records_rest.sorter import default_sorter_factory

    # for field in (['keyword']):
    #     if field not in request.values:
    #         raise RESTValidationError(
    #             errors=[FieldError(field, 'Required field.')])

    search, urlkwargs = default_facets_factory(search, "metadata")
    search, sortkwargs = default_sorter_factory(search, "metadata")
    for key, value in sortkwargs.items():
        urlkwargs.add(key, value)

    search = search.extra(size=0)

    # Apply 'identity' grouping by default
    search = search.filter(Q('term', RelationshipType='Cites'))
    if 'group_by' not in request.values:
        search = search.filter(Q('term', Grouping='identity'))
        urlkwargs['group_by'] = 'identity'

    try:
        query_string = request.values.get('q')
        if query_string:
            search = search.query(Q('query_string', query=query_string,
                                    default_field='_search_all'))
            urlkwargs['q'] = query_string
    except SyntaxError:
        raise InvalidQueryRESTError()
    size = 10
    if 'size' in request.values:    
        size = request.values.get('size')

    start = 0
    if 'page' in request.values:    
        start = int(int(request.values.get('page')) - 1) * int(size)

    search.aggs.bucket('Target', 'terms', field='Target.ID', size=1000)\
    .metric("first", "top_hits", _source=dict(include=["Target.Identifier.*", "Target.Creator.Name", "Target.Title"]),  size=1)
    kwargs = {'from':start, 'size':size, 'sort':[{'_count':{'order':'desc'}}]}
    search.aggs['Target'].bucket('pagination', 'bucket_sort', **kwargs)
    return search, urlkwargs


def enum_term_filter(label: str, field: str, choices: Dict[str, str]):
    """Term filter with controlled vocabulary."""
    def inner(values):
        if len(values) != 1:
            raise RESTValidationError(
                errors=[FieldError(label, 'Multiple values specified.')])
        term_value = choices.get(values[0])
        if not term_value:
            raise RESTValidationError(
                errors=[FieldError(
                    label, 'Allowed values: [{}]'.format(', '.join(choices)))])
        return Q('term', **{field: term_value})
    return inner


def nested_match_filter(field: str, path: str = None):
    """Nested match filter."""
    path = path or field.rsplit('.', 1)[0]
    def inner(values):
        return Q('nested', path=path, query=dict(match={field: values}))
    return inner

def simple_query_string_filter(field: str):
    """Simple query string filter."""
    def inner(values):
        return Q('simple_query_string',query=values[0], fields=[field], default_operator='AND')
    return inner

def nested_terms_filter(field: str, path: str = None):
    """Nested terms filter."""
    path = path or field.rsplit('.', 1)[0]
    def inner(values):
        return Q('nested', path=path, query=dict(terms={field: values}))
    return inner

def nested_range_filter(
        label: str, field: str, path: str = None, op: str = None):
    """Nested range filter."""
    path = path or field.rsplit('.', 1)[0]
    assert op in ('gte', 'gt', 'lte', 'lt')

    def inner(values):
        if len(values) != 1:
            raise RESTValidationError(
                errors=[FieldError(label, 'Multiple values specified.')])
        return Q('nested', path=path, query=Range(**{field: {op: values[0]}}))
    return inner