django-haystack 全文检索配置
一. 使用的工具
- haystack 是 django的开源搜索框架，该框架支持 Solr, Elasticsearch, Whoosh, *Xapian*搜索引擎，不用更改代码，直接切换引擎，减少代码量。
- 搜索引擎使用 whoosh，这是一个由纯 Python 实现的全文搜索引擎，没有二进制文件等，比较小巧，配置比较简单，当然性能自然略低。
- 中文分词 Jieba，由于 Whoosh 自带的是英文分词，对中文的分词支持不是太好，故用 jieba 替换 whoosh 的分词组件。
- 环境：Python 3.6.8, django 1.11.22, django-haystack 2.6.1, win7 x64
二. 配置过程
本人项目 app结构如图：（目的只是检索 文章 的标题 和 内容）
# models.py
# 主题表/文章表
class Article(models.Model):
author = models.ForeignKey(User, related_name="author_set", verbose_name="作者", on_delete=models.DO_NOTHING)
title = models.CharField(max_length=128, verbose_name="标题")
content = RichTextUploadingField(verbose_name="内容", config_name='awesome_ckeditor')
1. 首先安装各工具
pip install whoosh django-haystack jieba
2. 添加 Haystack 到 项目的 settings.py 的 INSTALLED_APPS
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'rest_framework',
'haystack', # Added. haystack先添加，自己的app要写在haystakc后面
'blog',
# ...
]
3. 配置结巴分词引擎
将 whoosh 库 下面的 whoosh_backend.py（该文件路径为 python路径/lib/python3.5/site-packages/haystack/backends/whoosh_backend.py）拷贝到 app下面，并重命名为 whoosh_cn_backend.py，例如blog/whoosh_cn_backend.py。修改的内容如下：
from jieba.analyse import ChineseAnalyzer # 结巴分词
# 注意先找到这个再修改，而不是直接添加，第 163 行左右，class WhooshSearchBackend -> def build_schema -> 第一个 for -> 第一个 else 下面
schema_fields[field_class.index_fieldname] = TEXT(stored=True, analyzer=ChineseAnalyzer(),field_boost=field_class.boost, sortable=True)
4. 修改 settings.py，以配置引擎
# HAYSTACK CONFIGS
HAYSTACK_CONNECTIONS = {
'default': {
# 'ENGINE': 'haystack.backends.whoosh_backend.WhooshEngine', # 使用默认引擎
'ENGINE': 'blog.whoosh_cn_backend.WhooshEngine', # 自定义引擎，app名称.分词文件名称.WhooshEngine
'PATH': os.path.join(os.path.dirname(__file__), 'whoosh_index'),
},
}
# HAYSTACK, 当添加、修改、删除数据时，自动生成索引
HAYSTACK_SIGNAL_PROCESSOR = 'haystack.signals.RealtimeSignalProcessor'
# HAYSTACK, 设置搜索结果页每页显示的数目，默认为20，可以自己修改
HAYSTACK_SEARCH_RESULTS_PER_PAGE = 10
# HAYSTACK, Handle a user-defined highlighting function. 处理用户定义的突出显示函数
HAYSTACK_CUSTOM_HIGHLIGHTER = "blog.templatetags.highlighting.Highlighter"
# whoosh_cn_backend.py
# encoding: utf-8
from __future__ import absolute_import, division, print_function, unicode_literals
import json
import os
import re
import shutil
import threading
import warnings
from django.conf import settings
from django.core.exceptions import ImproperlyConfigured
from django.utils import six
from django.utils.datetime_safe import datetime
from django.utils.encoding import force_text
from haystack.backends import BaseEngine, BaseSearchBackend, BaseSearchQuery, EmptyResults, log_query
from haystack.constants import DJANGO_CT, DJANGO_ID, ID
from haystack.exceptions import MissingDependency, SearchBackendError, SkipDocument
from haystack.inputs import Clean, Exact, PythonData, Raw
from haystack.models import SearchResult
from haystack.utils import log as logging
from haystack.utils import get_identifier, get_model_ct
from haystack.utils.app_loading import haystack_get_model
from jieba.analyse import ChineseAnalyzer # 结巴分词
try:
import whoosh
except ImportError:
raise MissingDependency("The 'whoosh' backend requires the installation of 'Whoosh'. Please refer to the documentation.")
# Handle minimum requirement.
if not hasattr(whoosh, '__version__') or whoosh.__version__ < (2, 5, 0):
raise MissingDependency("The 'whoosh' backend requires version 2.5.0 or greater.")
# Bubble up the correct error.
from whoosh import index
from whoosh.analysis import StemmingAnalyzer
from whoosh.fields import ID as WHOOSH_ID
from whoosh.fields import BOOLEAN, DATETIME, IDLIST, KEYWORD, NGRAM, NGRAMWORDS, NUMERIC, Schema, TEXT
from whoosh.filedb.filestore import FileStorage, RamStorage
from whoosh.highlight import highlight as whoosh_highlight
from whoosh.highlight import ContextFragmenter, HtmlFormatter
from whoosh.qparser import QueryParser
from whoosh.searching import ResultsPage
from whoosh.writing import AsyncWriter
DATETIME_REGEX = re.compile('^(?P<year>\d{4})-(?P<month>\d{2})-(?P<day>\d{2})T(?P<hour>\d{2}):(?P<minute>\d{2}):(?P<second>\d{2})(\.\d{3,6}Z?)?$')
LOCALS = threading.local()
LOCALS.RAM_STORE = None
class WhooshHtmlFormatter(HtmlFormatter):
"""
This is a HtmlFormatter simpler than the whoosh.HtmlFormatter.
We use it to have consistent results across backends. Specifically,
Solr, Xapian and Elasticsearch are using this formatting.
"""
template = '<%(tag)s>%(t)s</%(tag)s>'
class WhooshSearchBackend(BaseSearchBackend):
# Word reserved by Whoosh for special use.
RESERVED_WORDS = (
'AND',
'NOT',
'OR',
'TO',
)
# Characters reserved by Whoosh for special use.
# The '\\' must come first, so as not to overwrite the other slash replacements.
RESERVED_CHARACTERS = (
'\\', '+', '-', '&&', '||', '!', '(', ')', '{', '}',
'[', ']', '^', '"', '~', '*', '?', ':', '.',
)
def __init__(self, connection_alias, **connection_options):
super(WhooshSearchBackend, self).__init__(connection_alias, **connection_options)
self.setup_complete = False
self.use_file_storage = True
self.post_limit = getattr(connection_options, 'POST_LIMIT', 128 * 1024 * 1024)
self.path = connection_options.get('PATH')
if connection_options.get('STORAGE', 'file') != 'file':
self.use_file_storage = False
if self.use_file_storage and not self.path:
raise ImproperlyConfigured("You must specify a 'PATH' in your settings for connection '%s'." % connection_alias)
self.log = logging.getLogger('haystack')
def setup(self):
"""
Defers loading until needed.
"""
from haystack import connections
new_index = False
# Make sure the index is there.
if self.use_file_storage and not os.path.exists(self.path):
os.makedirs(self.path)
new_index = True
if self.use_file_storage and not os.access(self.path, os.W_OK):
raise IOError("The path to your Whoosh index '%s' is not writable for the current user/group." % self.path)
if self.use_file_storage:
self.storage = FileStorage(self.path)
else:
global LOCALS
if getattr(LOCALS, 'RAM_STORE', None) is None:
LOCALS.RAM_STORE = RamStorage()
self.storage = LOCALS.RAM_STORE
self.content_field_name, self.schema = self.build_schema(connections[self.connection_alias].get_unified_index().all_searchfields())
self.parser = QueryParser(self.content_field_name, schema=self.schema)
if new_index is True:
self.index = self.storage.create_index(self.schema)
else:
try:
self.index = self.storage.open_index(schema=self.schema)
except index.EmptyIndexError:
self.index = self.storage.create_index(self.schema)
self.setup_complete = True
def build_schema(self, fields):
schema_fields = {
ID: WHOOSH_ID(stored=True, unique=True),
DJANGO_CT: WHOOSH_ID(stored=True),
DJANGO_ID: WHOOSH_ID(stored=True),
}
# Grab the number of keys that are hard-coded into Haystack.
# We'll use this to (possibly) fail slightly more gracefully later.
initial_key_count = len(schema_fields)
content_field_name = ''
for field_name, field_class in fields.items():
if field_class.is_multivalued:
if field_class.indexed is False:
schema_fields[field_class.index_fieldname] = IDLIST(stored=True, field_boost=field_class.boost)
else:
schema_fields[field_class.index_fieldname] = KEYWORD(stored=True, commas=True, scorable=True, field_boost=field_class.boost)
elif field_class.field_type in ['date', 'datetime']:
schema_fields[field_class.index_fieldname] = DATETIME(stored=field_class.stored, sortable=True)
elif field_class.field_type == 'integer':
schema_fields[field_class.index_fieldname] = NUMERIC(stored=field_class.stored, numtype=int, field_boost=field_class.boost)
elif field_class.field_type == 'float':
schema_fields[field_class.index_fieldname] = NUMERIC(stored=field_class.stored, numtype=float, field_boost=field_class.boost)
elif field_class.field_type == 'boolean':
# Field boost isn't supported on BOOLEAN as of 1.8.2.
schema_fields[field_class.index_fieldname] = BOOLEAN(stored=field_class.stored)
elif field_class.field_type == 'ngram':
schema_fields[field_class.index_fieldname] = NGRAM(minsize=3, maxsize=15, stored=field_class.stored, field_boost=field_class.boost)
elif field_class.field_type == 'edge_ngram':
schema_fields[field_class.index_fieldname] = NGRAMWORDS(minsize=2, maxsize=15, at='start', stored=field_class.stored, field_boost=field_class.boost)
else:
# schema_fields[field_class.index_fieldname] = TEXT(stored=True, analyzer=StemmingAnalyzer(), field_boost=field_class.boost, sortable=True)
schema_fields[field_class.index_fieldname] = TEXT(stored=True, analyzer=ChineseAnalyzer(), field_boost=field_class.boost, sortable=True)
if field_class.document is True:
content_field_name = field_class.index_fieldname
schema_fields[field_class.index_fieldname].spelling = True
# Fail more gracefully than relying on the backend to die if no fields
# are found.
if len(schema_fields) <= initial_key_count:
raise SearchBackendError("No fields were found in any search_indexes. Please correct this before attempting to search.")
return (content_field_name, Schema(**schema_fields))
def update(self, index, iterable, commit=True):
if not self.setup_complete:
self.setup()
self.index = self.index.refresh()
writer = AsyncWriter(self.index)
for obj in iterable:
try:
doc = index.full_prepare(obj)
except SkipDocument:
self.log.debug(u"Indexing for object `%s` skipped", obj)
else:
# Really make sure it's unicode, because Whoosh won't have it any
# other way.
for key in doc:
doc[key] = self._from_python(doc[key])
# Document boosts aren't supported in Whoosh 2.5.0+.
if 'boost' in doc:
del doc['boost']
try:
writer.update_document(**doc)
except Exception as e:
if not self.silently_fail:
raise
# We'll log the object identifier but won't include the actual object
# to avoid the possibility of that generating encoding errors while
# processing the log message:
self.log.error(u"%s while preparing object for update" % e.__class__.__name__,
exc_info=True, extra={"data": {"index": index,
"object": get_identifier(obj)}})
if len(iterable) > 0:
# For now, commit no matter what, as we run into locking issues otherwise.
writer.commit()
def remove(self, obj_or_string, commit=True):
if not self.setup_complete:
self.setup()
self.index = self.index.refresh()
whoosh_id = get_identifier(obj_or_string)
try:
self.index.delete_by_query(q=self.parser.parse(u'%s:"%s"' % (ID, whoosh_id)))
except Exception as e:
if not self.silently_fail:
raise
self.log.error("Failed to remove document '%s' from Whoosh: %s", whoosh_id, e, exc_info=True)
def clear(self, models=None, commit=True):
if not self.setup_complete:
self.setup()
self.index = self.index.refresh()
if models is not None:
assert isinstance(models, (list, tuple))
try:
if models is None:
self.delete_index()
else:
models_to_delete = []
for model in models:
models_to_delete.append(u"%s:%s" % (DJANGO_CT, get_model_ct(model)))
self.index.delete_by_query(q=self.parser.parse(u" OR ".join(models_to_delete)))
except Exception as e:
if not self.silently_fail:
raise
if models is not None:
self.log.error("Failed to clear Whoosh index of models '%s': %s", ','.join(models_to_delete),
e, exc_info=True)
else:
self.log.error("Failed to clear Whoosh index: %s", e, exc_info=True)
def delete_index(self):
# Per the Whoosh mailing list, if wiping out everything from the index,
# it's much more efficient to simply delete the index files.
if self.use_file_storage and os.path.exists(self.path):
shutil.rmtree(self.path)
elif not self.use_file_storage:
self.storage.clean()
# Recreate everything.
self.setup()
def optimize(self):
if not self.setup_complete:
self.setup()
self.index = self.index.refresh()
self.index.optimize()
def calculate_page(self, start_offset=0, end_offset=None):
# Prevent against Whoosh throwing an error. Requires an end_offset
# greater than 0.
if not end_offset is None and end_offset <= 0:
end_offset = 1
# Determine the page.
page_num = 0
if end_offset is None:
end_offset = 1000000
if start_offset is None:
start_offset = 0
page_length = end_offset - start_offset
if page_length and page_length > 0:
page_num = int(start_offset / page_length)
# Increment because Whoosh uses 1-based page numbers.
page_num += 1
return page_num, page_length
@log_query
def search(self, query_string, sort_by=None, start_offset=0, end_offset=None,
fields='', highlight=False, facets=None, date_facets=None, query_facets=None,
narrow_queries=None, spelling_query=None, within=None,
dwithin=None, distance_point=None, models=None,
limit_to_registered_models=None, result_class=None, **kwargs):
if not self.setup_complete:
self.setup()
# A zero length query should return no results.
if len(query_string) == 0:
return {
'results': [],
'hits': 0,
}
query_string = force_text(query_string)
# A one-character query (non-wildcard) gets nabbed by a stopwords
# filter and should yield zero results.
if len(query_string) <= 1 and query_string != u'*':
return {
'results': [],
'hits': 0,
}
reverse = False
if sort_by is not None:
# Determine if we need to reverse the results and if Whoosh can
# handle what it's being asked to sort by. Reversing is an
# all-or-nothing action, unfortunately.
sort_by_list = []
reverse_counter = 0
for order_by in sort_by:
if order_by.startswith('-'):
reverse_counter += 1
if reverse_counter and reverse_counter != len(sort_by):
raise SearchBackendError("Whoosh requires all order_by fields"
" to use the same sort direction")
for order_by in sort_by:
if order_by.startswith('-'):
sort_by_list.append(order_by[1:])
if len(sort_by_list) == 1:
reverse = True
else:
sort_by_list.append(order_by)
if len(sort_by_list) == 1:
reverse = False
sort_by = sort_by_list[0]
if facets is not None:
warnings.warn("Whoosh does not handle faceting.", Warning, stacklevel=2)
if date_facets is not None:
warnings.warn("Whoosh does not handle date faceting.", Warning, stacklevel=2)
if query_facets is not None:
warnings.warn("Whoosh does not handle query faceting.", Warning, stacklevel=2)
narrowed_results = None
self.index = self.index.refresh()
if limit_to_registered_models is None:
limit_to_registered_models = getattr(settings, 'HAYSTACK_LIMIT_TO_REGISTERED_MODELS', True)
if models and len(models):
model_choices = sorted(get_model_ct(model) for model in models)
elif limit_to_registered_models:
# Using narrow queries, limit the results to only models handled
# with the current routers.
model_choices = self.build_models_list()
else:
model_choices = []
if len(model_choices) > 0:
if narrow_queries is None:
narrow_queries = set()
narrow_queries.add(' OR '.join(['%s:%s' % (DJANGO_CT, rm) for rm in model_choices]))
narrow_searcher = None
if narrow_queries is not None:
# Potentially expensive? I don't see another way to do it in Whoosh...
narrow_searcher = self.index.searcher()
for nq in narrow_queries:
recent_narrowed_results = narrow_searcher.search(self.parser.parse(force_text(nq)),
limit=None)
if len(recent_narrowed_results) <= 0:
return {
'results': [],
'hits': 0,
}
if narrowed_results:
narrowed_results.filter(recent_narrowed_results)
else:
narrowed_results = recent_narrowed_results
self.index = self.index.refresh()
if self.index.doc_count():
searcher = self.index.searcher()
parsed_query = self.parser.parse(query_string)
# In the event of an invalid/stopworded query, recover gracefully.
if parsed_query is None:
return {
'results': [],
'hits': 0,
}
page_num, page_length = self.calculate_page(start_offset, end_offset)
search_kwargs = {
'pagelen': page_length,
'sortedby': sort_by,
'reverse': reverse,
}
# Handle the case where the results have been narrowed.
if narrowed_results is not None:
search_kwargs['filter'] = narrowed_results
try:
raw_page = searcher.search_page(
parsed_query,
page_num,
**search_kwargs
)
except ValueError:
if not self.silently_fail:
raise
return {
'results': [],
'hits': 0,
'spelling_suggestion': None,
}
# Because as of Whoosh 2.5.1, it will return the wrong page of
# results if you request something too high. :(
if raw_page.pagenum < page_num:
return {
'results': [],
'hits': 0,
'spelling_suggestion': None,
}
results = self._process_results(raw_page, highlight=highlight, query_string=query_string, spelling_query=spelling_query, result_class=result_class)
searcher.close()
if hasattr(narrow_searcher, 'close'):
narrow_searcher.close()
return results
else:
if self.include_spelling:
if spelling_query:
spelling_suggestion = self.create_spelling_suggestion(spelling_query)
else:
spelling_suggestion = self.create_spelling_suggestion(query_string)
else:
spelling_suggestion = None
return {
'results': [],
'hits': 0,
'spelling_suggestion': spelling_suggestion,
}
def more_like_this(self, model_instance, additional_query_string=None,
start_offset=0, end_offset=None, models=None,
limit_to_registered_models=None, result_class=None, **kwargs):
if not self.setup_complete:
self.setup()
# Deferred models will have a different class ("RealClass_Deferred_fieldname")
# which won't be in our registry:
model_klass = model_instance._meta.concrete_model
field_name = self.content_field_name
narrow_queries = set()
narrowed_results = None
self.index = self.index.refresh()
if limit_to_registered_models is None:
limit_to_registered_models = getattr(settings, 'HAYSTACK_LIMIT_TO_REGISTERED_MODELS', True)
if models and len(models):
model_choices = sorted(get_model_ct(model) for model in models)
elif limit_to_registered_models:
# Using narrow queries, limit the results to only models handled
# with the current routers.
model_choices = self.build_models_list()
else:
model_choices = []
if len(model_choices) > 0:
if narrow_queries is None:
narrow_queries = set()
narrow_queries.add(' OR '.join(['%s:%s' % (DJANGO_CT, rm) for rm in model_choices]))
if additional_query_string and additional_query_string != '*':
narrow_queries.add(additional_query_string)
narrow_searcher = None
if narrow_queries is not None:
# Potentially expensive? I don't see another way to do it in Whoosh...
narrow_searcher = self.index.searcher()
for nq in narrow_queries:
recent_narrowed_results = narrow_searcher.search(self.parser.parse(force_text(nq)),
limit=None)
if len(recent_narrowed_results) <= 0:
return {
'results': [],
'hits': 0,
}
if narrowed_results:
narrowed_results.filter(recent_narrowed_results)
else:
narrowed_results = recent_narrowed_results
page_num, page_length = self.calculate_page(start_offset, end_offset)
self.index = self.index.refresh()
raw_results = EmptyResults()
if self.index.doc_count():
query = "%s:%s" % (ID, get_identifier(model_instance))
searcher = self.index.searcher()
parsed_query = self.parser.parse(query)
results = searcher.search(parsed_query)
if len(results):
raw_results = results[0].more_like_this(field_name, top=end_offset)
# Handle the case where the results have been narrowed.
if narrowed_results is not None and hasattr(raw_results, 'filter'):
raw_results.filter(narrowed_results)
try:
raw_page = ResultsPage(raw_results, page_num, page_length)
except ValueError:
if not self.silently_fail:
raise
return {
'results': [],
'hits': 0,
'spelling_suggestion': None,
}
# Because as of Whoosh 2.5.1, it will return the wrong page of
# results if you request something too high. :(
if raw_page.pagenum < page_num:
return {
'results': [],
'hits': 0,
'spelling_suggestion': None,
}
results = self._process_results(raw_page, result_class=result_class)
searcher.close()
if hasattr(narrow_searcher, 'close'):
narrow_searcher.close()
return results
def _process_results(self, raw_page, highlight=False, query_string='', spelling_query=None, result_class=None):
from haystack import connections
results = []
# It's important to grab the hits first before slicing. Otherwise, this
# can cause pagination failures.
hits = len(raw_page)
if result_class is None:
result_class = SearchResult
facets = {}
spelling_suggestion = None
unified_index = connections[self.connection_alias].get_unified_index()
indexed_models = unified_index.get_indexed_models()
for doc_offset, raw_result in enumerate(raw_page):
score = raw_page.score(doc_offset) or 0
app_label, model_name = raw_result[DJANGO_CT].split('.')
additional_fields = {}
model = haystack_get_model(app_label, model_name)
if model and model in indexed_models:
for key, value in raw_result.items():
index = unified_index.get_index(model)
string_key = str(key)
if string_key in index.fields and hasattr(index.fields[string_key], 'convert'):
# Special-cased due to the nature of KEYWORD fields.
if index.fields[string_key].is_multivalued:
if value is None or len(value) is 0:
additional_fields[string_key] = []
else:
additional_fields[string_key] = value.split(',')
else:
additional_fields[string_key] = index.fields[string_key].convert(value)
else:
additional_fields[string_key] = self._to_python(value)
del(additional_fields[DJANGO_CT])
del(additional_fields[DJANGO_ID])
if highlight:
sa = StemmingAnalyzer()
formatter = WhooshHtmlFormatter('em')
terms = [token.text for token in sa(query_string)]
whoosh_result = whoosh_highlight(
additional_fields.get(self.content_field_name),
terms,
sa,
ContextFragmenter(),
formatter
)
additional_fields['highlighted'] = {
self.content_field_name: [whoosh_result],
}
result = result_class(app_label, model_name, raw_result[DJANGO_ID], score, **additional_fields)
results.append(result)
else:
hits -= 1
if self.include_spelling:
if spelling_query:
spelling_suggestion = self.create_spelling_suggestion(spelling_query)
else:
spelling_suggestion = self.create_spelling_suggestion(query_string)
return {
'results': results,
'hits': hits,
'facets': facets,
'spelling_suggestion': spelling_suggestion,
}
def create_spelling_suggestion(self, query_string):
spelling_suggestion = None
reader = self.index.reader()
corrector = reader.corrector(self.content_field_name)
cleaned_query = force_text(query_string)
if not query_string:
return spelling_suggestion
# Clean the string.
for rev_word in self.RESERVED_WORDS:
cleaned_query = cleaned_query.replace(rev_word, '')
for rev_char in self.RESERVED_CHARACTERS:
cleaned_query = cleaned_query.replace(rev_char, '')
# Break it down.
query_words = cleaned_query.split()
suggested_words = []
for word in query_words:
suggestions = corrector.suggest(word, limit=1)
if len(suggestions) > 0:
suggested_words.append(suggestions[0])
spelling_suggestion = ' '.join(suggested_words)
return spelling_suggestion
def _from_python(self, value):
"""
Converts Python values to a string for Whoosh.
Code courtesy of pysolr.
"""
if hasattr(value, 'strftime'):
if not hasattr(value, 'hour'):
value = datetime(value.year, value.month, value.day, 0, 0, 0)
elif isinstance(value, bool):
if value:
value = 'true'
else:
value = 'false'
elif isinstance(value, (list, tuple)):
value = u','.join([force_text(v) for v in value])
elif isinstance(value, (six.integer_types, float)):
# Leave it alone.
pass
else:
value = force_text(value)
return value
def _to_python(self, value):
"""
Converts values from Whoosh to native Python values.
A port of the same method in pysolr, as they deal with data the same way.
"""
if value == 'true':
return True
elif value == 'false':
return False
if value and isinstance(value, six.string_types):
possible_datetime = DATETIME_REGEX.search(value)
if possible_datetime:
date_values = possible_datetime.groupdict()
for dk, dv in date_values.items():
date_values[dk] = int(dv)
return datetime(date_values['year'], date_values['month'], date_values['day'], date_values['hour'], date_values['minute'], date_values['second'])
try:
# Attempt to use json to load the values.
converted_value = json.loads(value)
# Try to handle most built-in types.
if isinstance(converted_value, (list, tuple, set, dict, six.integer_types, float, complex)):
return converted_value
except:
# If it fails (SyntaxError or its ilk) or we don't trust it,
# continue on.
pass
return value
class WhooshSearchQuery(BaseSearchQuery):
def _convert_datetime(self, date):
if hasattr(date, 'hour'):
return force_text(date.strftime('%Y%m%d%H%M%S'))
else:
return force_text(date.strftime('%Y%m%d000000'))
def clean(self, query_fragment):
"""
Provides a mechanism for sanitizing user input before presenting the
value to the backend.
Whoosh 1.X differs here in that you can no longer use a backslash
to escape reserved characters. Instead, the whole word should be
quoted.
"""
words = query_fragment.split()
cleaned_words = []
for word in words:
if word in self.backend.RESERVED_WORDS:
word = word.replace(word, word.lower())
for char in self.backend.RESERVED_CHARACTERS:
if char in word:
word = "'%s'" % word
break
cleaned_words.append(word)
return ' '.join(cleaned_words)
def build_query_fragment(self, field, filter_type, value):
from haystack import connections
query_frag = ''
is_datetime = False
if not hasattr(value, 'input_type_name'):
# Handle when we've got a ``ValuesListQuerySet``...
if hasattr(value, 'values_list'):
value = list(value)
if hasattr(value, 'strftime'):
is_datetime = True
if isinstance(value, six.string_types) and value != ' ':
# It's not an ``InputType``. Assume ``Clean``.
value = Clean(value)
else:
value = PythonData(value)
# Prepare the query using the InputType.
prepared_value = value.prepare(self)
if not isinstance(prepared_value, (set, list, tuple)):
# Then convert whatever we get back to what pysolr wants if needed.
prepared_value = self.backend._from_python(prepared_value)
# 'content' is a special reserved word, much like 'pk' in
# Django's ORM layer. It indicates 'no special field'.
if field == 'content':
index_fieldname = ''
else:
index_fieldname = u'%s:' % connections[self._using].get_unified_index().get_index_fieldname(field)
filter_types = {
'content': '%s',
'contains': '*%s*',
'endswith': "*%s",
'startswith': "%s*",
'exact': '%s',
'gt': "{%s to}",
'gte': "[%s to]",
'lt': "{to %s}",
'lte': "[to %s]",
'fuzzy': u'%s~',
}
if value.post_process is False:
query_frag = prepared_value
else:
if filter_type in ['content', 'contains', 'startswith', 'endswith', 'fuzzy']:
if value.input_type_name == 'exact':
query_frag = prepared_value
else:
# Iterate over terms & incorportate the converted form of each into the query.
terms = []
if isinstance(prepared_value, six.string_types):
possible_values = prepared_value.split(' ')
else:
if is_datetime is True:
prepared_value = self._convert_datetime(prepared_value)
possible_values = [prepared_value]
for possible_value in possible_values:
terms.append(filter_types[filter_type] % self.backend._from_python(possible_value))
if len(terms) == 1:
query_frag = terms[0]
else:
query_frag = u"(%s)" % " AND ".join(terms)
elif filter_type == 'in':
in_options = []
for possible_value in prepared_value:
is_datetime = False
if hasattr(possible_value, 'strftime'):
is_datetime = True
pv = self.backend._from_python(possible_value)
if is_datetime is True:
pv = self._convert_datetime(pv)
if isinstance(pv, six.string_types) and not is_datetime:
in_options.append('"%s"' % pv)
else:
in_options.append('%s' % pv)
query_frag = "(%s)" % " OR ".join(in_options)
elif filter_type == 'range':
start = self.backend._from_python(prepared_value[0])
end = self.backend._from_python(prepared_value[1])
if hasattr(prepared_value[0], 'strftime'):
start = self._convert_datetime(start)
if hasattr(prepared_value[1], 'strftime'):
end = self._convert_datetime(end)
query_frag = u"[%s to %s]" % (start, end)
elif filter_type == 'exact':
if value.input_type_name == 'exact':
query_frag = prepared_value
else:
prepared_value = Exact(prepared_value).prepare(self)
query_frag = filter_types[filter_type] % prepared_value
else:
if is_datetime is True:
prepared_value = self._convert_datetime(prepared_value)
query_frag = filter_types[filter_type] % prepared_value
if len(query_frag) and not isinstance(value, Raw):
if not query_frag.startswith('(') and not query_frag.endswith(')'):
query_frag = "(%s)" % query_frag
return u"%s%s" % (index_fieldname, query_frag)
# if not filter_type in ('in', 'range'):
# # 'in' is a bit of a special case, as we don't want to
# # convert a valid list/tuple to string. Defer handling it
# # until later...
# value = self.backend._from_python(value)
class WhooshEngine(BaseEngine):
backend = WhooshSearchBackend
query = WhooshSearchQuery
5. 创建索引
如果你想针对某个 app 例如 blog 做全文检索，则必须在 blog 的目录下面建立 search_indexes.py 文件，文件名不能修改。内容如下：
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
__author__ = 'yinzhuoqun'
# import datetime
from haystack import indexes
from blog.models import Article
# 类名必须为需要检索的 Model_name + Index，这里需要检索Article，所以创建ArticleIndex
class ArticleIndex(indexes.SearchIndex, indexes.Indexable):
text = indexes.CharField(document=True, use_template=True) # 创建一个text字段
author = indexes.CharField(model_attr='author') # 创建一个author字段
pub_date = indexes.DateTimeField(model_attr='time_created') # 创建一个pub_date字段
def get_model(self): # 重载 get_model方法，必须要有！
return Article
def index_queryset(self, using=None): # 重载index_..函数
"""Used when the entire index for model is updated."""
return self.get_model().objects.filter(show_status=True).order_by('-pub_date')
每个索引里面必须有且只能有一个字段为 document=True，这代表 haystack 和搜索引擎将使用此字段的内容作为索引进行检索(primary field)。其他的字段只是附属的属性，方便调用，并不作为检索数据。
注意：如果使用一个字段设置了 document=True，则一般约定此字段名为text，这是在 SearchIndex类里面一贯的命名，以防止后台混乱，当然名字你也可以随便改，不过不建议改。
并且，haystack 提供了 use_template=True 在 text字段，这样就允许我们使用数据模板去建立搜索引擎索引的文件，使用方便（官方推荐，当然还有其他复杂的建立索引文件的方式，目前我还不知道），数据模板的路径为 youapp/templates/search/indexes/youapp/article_text.txt，例如本例子为 blog/templates/search/indexes/blog/article_text.txt 文件名必须为要索引的 类名_text.txt, 其内容为：
{{ object.title }}
{{ object.content }}
{{ object.author.username }}
这个数据模板的作用是对 Article.title, Article.content, Article.author( ForeignKey ) 这几个字段建立索引，当检索的时候会对这三个字段做全文检索匹配。
6. 在 app 下的 urls.py 配置中添加 SearchView，并配置模板
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
from django.conf.urls import url, include
from blog import views
from haystack.views import SearchView
urlpatterns = [
url(r'^$', views.IndexView.as_view(), name='index'),
url(r'^search/', views.MySeachView(), name='search'),
]
# views.py
class MySeachView(SearchView):
template = 'search/search.html'
def extra_context(self): # 重载extra_context来添加额外的context内容
context = super(MySeachView, self).extra_context()
# context['nodes'] = Node.objects.filter().order_by("-id")
return context
SearchView()视图函数默认使用的 html 模板为 当前app目录下，路径为 myapp/templates/search/search.html
所以需要在 blog/templates/search/下添加 search.html文件，内容为：
{% block article_list %}
<div class="am-u-md-8 am-u-sm-12">
{# {% if page %}#}
{# <h2>搜索 <b>{% myhighlight query with query css_class "myhighlight" html_tag "span" %}</b> 结果如下：#}
{# </h2>#}
{# {% endif %}#}
{% for article in page %}
<article class="am-g blog-entry-article">
<div class="am-u-lg-6 am-u-md-12 am-u-sm-12 blog-entry-img">
<a href="{% url 'blog:detail' article.object.id %}">
<img src="{{ article.object.get_contentimg_url }}"
onerror="this.src='http://photo.python3.top/f161.jpg'"
alt="" class="am-u-sm-12">
</a>
</div>
<div class="am-u-lg-6 am-u-md-12 am-u-sm-12 blog-entry-text">
<span><a href="{% url "blog:node" article.object.node %}" class="blog-color">{{ article.object.node }} </a></span>
<span class="am-icon-user"> {{ article.object.author }} </span>
<span class="am-icon-clock-o"> {{ article.object.time_created | date:"Y/n/j" }} </span>
<span class="am-icon-eye"> {{ article.object.num_views|add:"20" }} </span>
{# <h1><a href="{% url 'blog:detail' article.object.id %}">{{ article.object.title | capfirst }}</a>#}
<h1>
<a href="{% url 'blog:detail' article.object.id %}">{% myhighlight article.object.title with query css_class "myhighlight" html_tag "span" %}</a>
</h1>
{# {% myhighlight article.object.content with query css_class "myhighlight" html_tag "span" max_length 100 %}#}
{# <a href="{% url 'blog:detail' article.object.id %}">#}
{% if "img" and "src=" in article.content|truncatechars_html:30 %}
{% myhighlight article.object.content with query css_class "myhighlight" html_tag "span" max_length 100 %}
{# {{ article.content | truncatechars_html:30 }}#}
{% else %}
{% myhighlight article.object.content with query css_class "myhighlight" html_tag "span" max_length 100 %}
{# {{ article.content | truncatechars_html:30 | safe }}#}
{% endif %}
{# </a>#}
<p><a href="" class="blog-continue">continue reading</a></p>
</div>
</article>
{% empty %}
<h1>Sorry，未找到与 {% myhighlight query with query css_class "myhighlight" html_tag "span" %} 相关的文章</h1>
{% endfor %}
<ul data-am-widget="pagination" class="am-pagination am-pagination-select">
{% if page.has_previous %}
<li class="am-pagination-prev"><a href="?q={{ query }}&page={{ page.previous_page_number }}">«
Prev</a></li>
{% endif %}
{% if page.paginator.num_pages != 1 %}
<li class="am-pagination-select">
<select id="page-select" onchange="window.location=this.value;" autocomplete="off">
{% for page_num in page.paginator.page_range %}
{% if page.number == page_num %}
<option value="?q={{ query }}&page={{ page_num }}" class="" selected="selected">
{{ page_num }}/{{ page.paginator.num_pages }}
</option>
{% else %}
<option value="?q={{ query }}&page={{ page_num }}" class="">
{{ page_num }}/{{ page.paginator.num_pages }}
{% endif %}
{% endfor %}
</select>
</li>
{% endif %}
{% if page.has_next %}
<li class="am-pagination-next"><a href="?q={{ query }}&page={{ page.next_page_number }}">Next
»</a></li>
{% endif %}
</ul>
</div>
{% endblock %}
7. 最后一步，重建索引文件
# 项目路径 >python manage.py
[haystack]
build_solr_schema
clear_index
haystack_info
rebuild_index
update_index
使用 python manage.py rebuild_index 或者使用 update_index命令。
三. 效果图
搜索 django ：(关键词高亮)
^_^
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