Files
mayan-edms/apps/dynamic_search/classes.py
2013-01-04 07:48:35 -04:00

222 lines
8.0 KiB
Python

from __future__ import absolute_import
import re
import types
import logging
import datetime
from django.db.models import Q
from django.db.models.loading import get_model
from .conf.settings import LIMIT
logger = logging.getLogger(__name__)
class SearchModel(object):
registry = {}
@classmethod
def get_all(cls):
return cls.registry.values()
def __init__(self, app_label, model_name, label=None):
self.app_label = app_label
self.model_name = model_name
self.search_fields = []
self.model = get_model(app_label, model_name)
self.label = label or self.model._meta.verbose_name
self.__class__.registry[id(self)] = self
def get_fields_simple_list(self):
"""
Returns a list of the fields for the SearchModel
"""
result = []
for search_field in self.search_fields:
result.append((search_field.get_full_name(), search_field.label))
return result
def add_model_field(self, *args, **kwargs):
"""
Add a search field that directly belongs to the parent SearchModel
"""
self.search_fields.append(SearchField(self, *args, **kwargs))
def add_related_field(self, *args, **kwargs):
"""
Add a search field that will search content in a related field in
a separate model
"""
self.search_fields.append(RelatedSearchField(self, *args, **kwargs))
def normalize_query(self, query_string,
findterms=re.compile(r'"([^"]+)"|(\S+)').findall,
normspace=re.compile(r'\s{2,}').sub):
"""
Splits the query string in invidual keywords, getting rid of unecessary spaces
and grouping quoted words together.
Example:
>>> normalize_query(' some random words "with quotes " and spaces')
['some', 'random', 'words', 'with quotes', 'and', 'spaces']
"""
return [normspace(' ', (t[0] or t[1]).strip()) for t in findterms(query_string)]
def simple_search(self, query_string):
search_dict = {}
model_list = {}
flat_list = []
result_count = 0
shown_result_count = 0
elapsed_time = 0
start_time = datetime.datetime.now()
for search_field in self.search_fields:
search_dict.setdefault(search_field.get_model(), {
'searches': [],
'label': search_field.label,
'return_value': search_field.return_value
})
search_dict[search_field.get_model()]['searches'].append(
{
'field_name': [search_field.field],
'terms': self.normalize_query(query_string)
}
)
logger.debug('search_dict: %s' % search_dict)
for model, data in search_dict.items():
logger.debug('model: %s' % model)
# Initialize per model result set
model_result_set = set()
for query_entry in data['searches']:
# Fashion a list of queries for a field for each term
field_query_list = self.assemble_query(query_entry['terms'], query_entry['field_name'])
logger.debug('field_query_list: %s' % field_query_list)
# Initialize per field result set
field_result_set = set()
# Get results per search field
for query in field_query_list:
logger.debug('query: %s' % query)
term_query_result_set = set(model.objects.filter(query).values_list(data['return_value'], flat=True))
# Convert the QuerySet to a Python set and perform the
# AND operation on the program and not as a query.
# This operation ANDs all the field term results
# belonging to a single model, making sure to only include
# results in the final field result variable if all the terms
# are found in a single field.
if not field_result_set:
field_result_set = term_query_result_set
else:
field_result_set &= term_query_result_set
logger.debug('term_query_result_set: %s' % term_query_result_set)
logger.debug('field_result_set: %s' % field_result_set)
model_result_set |= field_result_set
logger.debug('model_result_set: %s' % model_result_set)
# Update the search result total count
result_count += len(model_result_set)
# Search the field results return values (PK) in the SearchModel's model
results = self.model.objects.in_bulk(list(model_result_set)[: LIMIT]).values()
# Update the search result visible count (limited by LIMIT config option)
shown_result_count += len(results)
if results:
model_list[data['label']] = results
for result in results:
if result not in flat_list:
flat_list.append(result)
logger.debug('model_list: %s' % model_list)
logger.debug('flat_list: %s' % flat_list)
elapsed_time = unicode(datetime.datetime.now() - start_time).split(':')[2]
return model_list, flat_list, shown_result_count, result_count, elapsed_time
def advanced_search(self, dictionary):
for key, value in dictionary.items():
try:
model, field_name = key.split('__', 1)
model_entry = registered_search_dict.get(model, {})
if model_entry:
for model_field in model_entry.get('fields', [{}]):
if model_field.get('name') == field_name:
search_dict.setdefault(model_entry['model'], {'query_entries': [], 'label': model_entry['label']})
search_dict[model_entry['model']]['query_entries'].append(
{
'field_name': [field_name],
'terms': normalize_query(value.strip())
}
)
except ValueError:
pass
def assemble_query(self, terms, search_fields):
"""
Returns a query, that is a combination of Q objects. That combination
aims to search keywords within a model by testing the given search fields.
"""
queries = []
for term in terms:
or_query = None
for field in search_fields:
q = Q(**{'%s__%s' % (field, 'icontains'): term})
if or_query is None:
or_query = q
else:
or_query = or_query | q
queries.append(or_query)
return queries
# SearchField classes
class SearchField(object):
"""
Search for terms in fields that directly belong to the parent SearchModel
"""
def __init__(self, search_model, field, label):
self.search_model = search_model
self.field = field
self.label = label
self.return_value = 'pk'
def get_full_name(self):
return self.field
def get_model(self):
return self.search_model.model
class RelatedSearchField(object):
"""
Search for terms in fields that are related to the parent SearchModel
"""
def __init__(self, search_model, app_label, model_name, field, return_value, label):
self.search_model = search_model
self.app_label = app_label
self.model_name = model_name
self.field = field
self.return_value = return_value
self.model = get_model(app_label, model_name)
self.label = label
def get_full_name(self):
return '%s.%s.%s' % (self.app_label, self.model_name, self.field)
def get_model(self):
return self.model