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from six import iteritems, string_types
from elasticsearch.helpers import scan
from .query import Q, EMPTY_QUERY, Bool
from .aggs import A, AggBase
from .utils import DslBase
from .result import Response, Result, SuggestResponse
from .connections import connections
class QueryProxy(object):
"""
Simple proxy around DSL objects (queries) that can be called
(to add query/post_filter) and also allows attribute access which is proxied to
the wrapped query.
"""
def __init__(self, search, attr_name):
self._search = search
self._proxied = EMPTY_QUERY
self._attr_name = attr_name
def __nonzero__(self):
return self._proxied != EMPTY_QUERY
__bool__ = __nonzero__
def __call__(self, *args, **kwargs):
s = self._search._clone()
getattr(s, self._attr_name)._proxied += Q(*args, **kwargs)
# always return search to be chainable
return s
def __getattr__(self, attr_name):
return getattr(self._proxied, attr_name)
def __setattr__(self, attr_name, value):
if not attr_name.startswith('_'):
self._proxied = Q(self._proxied.to_dict())
setattr(self._proxied, attr_name, value)
super(QueryProxy, self).__setattr__(attr_name, value)
class ProxyDescriptor(object):
"""
Simple descriptor to enable setting of queries and filters as:
s = Search()
s.query = Q(...)
"""
def __init__(self, name):
self._attr_name = '_%s_proxy' % name
def __get__(self, instance, owner):
return getattr(instance, self._attr_name)
def __set__(self, instance, value):
proxy = getattr(instance, self._attr_name)
proxy._proxied = Q(value)
class AggsProxy(AggBase, DslBase):
name = 'aggs'
def __init__(self, search):
self._base = self._search = search
self._params = {'aggs': {}}
def to_dict(self):
return super(AggsProxy, self).to_dict().get('aggs', {})
class Request(object):
def __init__(self, using='default', index=None, doc_type=None, extra=None):
self._using = using
self._index = None
if isinstance(index, (tuple, list)):
self._index = list(index)
elif index:
self._index = [index]
self._doc_type = []
self._doc_type_map = {}
if isinstance(doc_type, (tuple, list)):
for dt in doc_type:
self._add_doc_type(dt)
elif isinstance(doc_type, dict):
self._doc_type.extend(doc_type.keys())
self._doc_type_map.update(doc_type)
elif doc_type:
self._add_doc_type(doc_type)
self._params = {}
self._extra = extra or {}
def params(self, **kwargs):
"""
Specify query params to be used when executing the search. All the
keyword arguments will override the current values. See
http://elasticsearch-py.readthedocs.org/en/master/api.html#elasticsearch.Elasticsearch.search
for all availible parameters.
Example::
s = Search()
s = s.params(routing='user-1', preference='local')
"""
s = self._clone()
s._params.update(kwargs)
return s
def index(self, *index):
"""
Set the index for the search. If called empty it will rmove all information.
Example:
s = Search()
s = s.index('twitter-2015.01.01', 'twitter-2015.01.02')
"""
# .index() resets
s = self._clone()
if not index:
s._index = None
else:
s._index = (self._index or []) + list(index)
return s
def _add_doc_type(self, doc_type):
if hasattr(doc_type, '_doc_type'):
self._doc_type_map[doc_type._doc_type.name] = doc_type.from_es
doc_type = doc_type._doc_type.name
self._doc_type.append(doc_type)
def doc_type(self, *doc_type, **kwargs):
"""
Set the type to search through. You can supply a single value or
multiple. Values can be strings or subclasses of ``DocType``.
You can also pass in any keyword arguments, mapping a doc_type to a
callback that should be used instead of the Result class.
If no doc_type is supplied any information stored on the instance will
be erased.
Example:
s = Search().doc_type('product', 'store', User, custom=my_callback)
"""
# .doc_type() resets
s = self._clone()
if not doc_type and not kwargs:
s._doc_type = []
s._doc_type_map = {}
else:
for dt in doc_type:
s._add_doc_type(dt)
s._doc_type.extend(kwargs.keys())
s._doc_type_map.update(kwargs)
return s
def using(self, client):
"""
Associate the search request with an elasticsearch client. A fresh copy
will be returned with current instance remaining unchanged.
:arg client: an instance of ``elasticsearch.Elasticsearch`` to use or
an alias to look up in ``elasticsearch_dsl.connections``
"""
s = self._clone()
s._using = client
return s
def extra(self, **kwargs):
"""
Add extra keys to the request body. Mostly here for backwards
compatibility.
"""
s = self._clone()
if 'from_' in kwargs:
kwargs['from'] = kwargs.pop('from_')
s._extra.update(kwargs)
return s
def _clone(self):
s = self.__class__(using=self._using, index=self._index,
doc_type=self._doc_type)
s._doc_type_map = self._doc_type_map.copy()
s._extra = self._extra.copy()
s._params = self._params.copy()
return s
class Search(Request):
query = ProxyDescriptor('query')
post_filter = ProxyDescriptor('post_filter')
def __init__(self, **kwargs):
"""
Search request to elasticsearch.
:arg using: `Elasticsearch` instance to use
:arg index: limit the search to index
:arg doc_type: only query this type.
All the paramters supplied (or omitted) at creation type can be later
overriden by methods (`using`, `index` and `doc_type` respectively).
"""
super(Search, self).__init__(**kwargs)
self.aggs = AggsProxy(self)
self._sort = []
self._fields = None
self._partial_fields = {}
self._highlight = {}
self._highlight_opts = {}
self._suggest = {}
self._script_fields = {}
self._response_class = Response
self._query_proxy = QueryProxy(self, 'query')
self._post_filter_proxy = QueryProxy(self, 'post_filter')
def filter(self, *args, **kwargs):
return self.query(Bool(filter=[Q(*args, **kwargs)]))
def __iter__(self):
"""
Iterate over the hits.
"""
return iter(self.execute())
def __getitem__(self, n):
"""
Support slicing the `Search` instance for pagination.
Slicing equates to the from/size parameters. E.g.::
s = Search().query(...)[0:25]
is equivalent to::
s = Search().query(...).extra(from_=0, size=25)
"""
s = self._clone()
if isinstance(n, slice):
# If negative slicing, abort.
if n.start and n.start < 0 or n.stop and n.stop < 0:
raise ValueError("Search does not support negative slicing.")
# Elasticsearch won't get all results so we default to size: 10 if
# stop not given.
s._extra['from'] = n.start or 0
s._extra['size'] = n.stop - (n.start or 0) if n.stop is not None else 10
return s
else: # This is an index lookup, equivalent to slicing by [n:n+1].
# If negative index, abort.
if n < 0:
raise ValueError("Search does not support negative indexing.")
s._extra['from'] = n
s._extra['size'] = 1
return s
@classmethod
def from_dict(cls, d):
"""
Construct a `Search` instance from a raw dict containing the search
body. Useful when migrating from raw dictionaries.
Example::
s = Search.from_dict({
"query": {
"bool": {
"must": [...]
}
},
"aggs": {...}
})
s = s.filter('term', published=True)
"""
s = cls()
s.update_from_dict(d)
return s
def _clone(self):
"""
Return a clone of the current search request. Performs a shallow copy
of all the underlying objects. Used internally by most state modifying
APIs.
"""
s = super(Search, self)._clone()
s._response_class = self._response_class
s._sort = self._sort[:]
s._fields = self._fields[:] if self._fields is not None else None
s._partial_fields = self._partial_fields.copy()
s._highlight = self._highlight.copy()
s._highlight_opts = self._highlight_opts.copy()
s._suggest = self._suggest.copy()
s._script_fields = self._script_fields.copy()
for x in ('query', 'post_filter'):
getattr(s, x)._proxied = getattr(self, x)._proxied
# copy top-level bucket definitions
if self.aggs._params.get('aggs'):
s.aggs._params = {'aggs': self.aggs._params['aggs'].copy()}
return s
def response_class(self, cls):
"""
Override the default wrapper used for the response.
"""
s = self._clone()
s._response_class = cls
return s
def update_from_dict(self, d):
"""
Apply options from a serialized body to the current instance. Modifies
the object in-place. Used mostly by ``from_dict``.
"""
d = d.copy()
if 'query' in d:
self.query._proxied = Q(d.pop('query'))
if 'post_filter' in d:
self.post_filter._proxied = Q(d.pop('post_filter'))
aggs = d.pop('aggs', d.pop('aggregations', {}))
if aggs:
self.aggs._params = {
'aggs': dict(
(name, A(value)) for (name, value) in iteritems(aggs))
}
if 'sort' in d:
self._sort = d.pop('sort')
if 'fields' in d:
self._fields = d.pop('fields')
if 'partial_fields' in d:
self._partial_fields = d.pop('partial_fields')
if 'highlight' in d:
high = d.pop('highlight').copy()
self._highlight = high.pop('fields')
self._highlight_opts = high
if 'suggest' in d:
self._suggest = d.pop('suggest')
if 'text' in self._suggest:
text = self._suggest.pop('text')
for s in self._suggest.values():
s.setdefault('text', text)
if 'script_fields' in d:
self._script_fields = d.pop('script_fields')
self._extra = d
def script_fields(self, **kwargs):
"""
Define script fields to be calculated on hits. See
https://www.elastic.co/guide/en/elasticsearch/reference/current/search-request-script-fields.html
for more details.
Example::
s = Search()
s = s.script_fields(times_two="doc['field'].value * 2")
s = s.script_fields(
times_three={
'script': "doc['field'].value * n",
'params': {'n': 3}
}
)
"""
s = self._clone()
for name in kwargs:
if isinstance(kwargs[name], string_types):
kwargs[name] = {'script': kwargs[name]}
s._script_fields.update(kwargs)
return s
def fields(self, fields=None):
"""
Selectively load specific stored fields for each document.
:arg fields: list of fields to return for each document
If ``fields`` is None, the entire document will be returned for
each hit. If fields is the empty list, no fields will be
returned for each hit, just the metadata.
"""
s = self._clone()
s._fields = fields
return s
def partial_fields(self, **partial):
"""
Control which part of the fields to extract from the `_source` document
:kwargs partial: dict specifying which fields to extract from the source
An example usage would be:
s = Search().partial_fields(authors_data={
'include': ['authors.*'],
'exclude': ['authors.name']
})
which will include all fields from the `authors` nested property except for
each authors `name`
If ``partial`` is not provided, the whole `_source` will be fetched. Calling this multiple
times will override the previous values with the new ones.
"""
s = self._clone()
s._partial_fields = partial
return s
def sort(self, *keys):
"""
Add sorting information to the search request. If called without
arguments it will remove all sort requirements. Otherwise it will
replace them. Acceptable arguments are::
'some.field'
'-some.other.field'
{'different.field': {'any': 'dict'}}
so for example::
s = Search().sort(
'category',
'-title',
{"price" : {"order" : "asc", "mode" : "avg"}}
)
will sort by ``category``, ``title`` (in descending order) and
``price`` in ascending order using the ``avg`` mode.
The API returns a copy of the Search object and can thus be chained.
"""
s = self._clone()
s._sort = []
for k in keys:
if isinstance(k, string_types) and k.startswith('-'):
k = {k[1:]: {"order": "desc"}}
s._sort.append(k)
return s
def highlight_options(self, **kwargs):
"""
Update the global highlighting options used for this request. For
example::
s = Search()
s = s.highlight_options(order='score')
"""
s = self._clone()
s._highlight_opts.update(kwargs)
return s
def highlight(self, *fields, **kwargs):
"""
Request highliting of some fields. All keyword arguments passed in will be
used as parameters. Example::
Search().highlight('title', 'body', fragment_size=50)
will produce the equivalent of::
{
"highlight": {
"fields": {
"body": {"fragment_size": 50},
"title": {"fragment_size": 50}
}
}
}
"""
s = self._clone()
for f in fields:
s._highlight[f] = kwargs
return s
def suggest(self, name, text, **kwargs):
"""
Add a suggestions request to the search.
:arg name: name of the suggestion
:arg text: text to suggest on
All keyword arguments will be added to the suggestions body. For example::
s = Search()
s = s.suggest('suggestion-1', 'Elasticserach', term={'field': 'body'})
"""
s = self._clone()
s._suggest[name] = {'text': text}
s._suggest[name].update(kwargs)
return s
def to_dict(self, count=False, **kwargs):
"""
Serialize the search into the dictionary that will be sent over as the
request's body.
:arg count: a flag to specify we are interested in a body for count -
no aggregations, no pagination bounds etc.
All additional keyword arguments will be included into the dictionary.
"""
d = {"query": self.query.to_dict()}
if self.post_filter:
d['post_filter'] = self.post_filter.to_dict()
# count request doesn't care for sorting and other things
if not count:
if self.aggs.aggs:
d.update(self.aggs.to_dict())
if self._sort:
d['sort'] = self._sort
d.update(self._extra)
if self._fields is not None:
d['fields'] = self._fields
if self._partial_fields:
d['partial_fields'] = self._partial_fields
if self._highlight:
d['highlight'] = {'fields': self._highlight}
d['highlight'].update(self._highlight_opts)
if self._suggest:
d['suggest'] = self._suggest
if self._script_fields:
d['script_fields'] = self._script_fields
d.update(kwargs)
return d
def count(self):
"""
Return the number of hits matching the query and filters. Note that
only the actual number is returned.
"""
if hasattr(self, '_response'):
return self._response.hits.total
es = connections.get_connection(self._using)
d = self.to_dict(count=True)
# TODO: failed shards detection
return es.count(
index=self._index,
doc_type=self._doc_type,
body=d
)['count']
def execute(self, ignore_cache=False):
"""
Execute the search and return an instance of ``Response`` wrapping all
the data.
:arg response_class: optional subclass of ``Response`` to use instead.
"""
if ignore_cache or not hasattr(self, '_response'):
es = connections.get_connection(self._using)
self._response = self._response_class(
es.search(
index=self._index,
doc_type=self._doc_type,
body=self.to_dict(),
**self._params
),
callbacks=self._doc_type_map
)
return self._response
def execute_suggest(self):
"""
Execute just the suggesters. Ignores all parts of the request that are
not relevant, including ``query`` and ``doc_type``.
"""
es = connections.get_connection(self._using)
return SuggestResponse(
es.suggest(
index=self._index,
body=self._suggest,
**self._params
)
)
def scan(self):
"""
Turn the search into a scan search and return a generator that will
iterate over all the documents matching the query.
Use ``params`` method to specify any additional arguments you with to
pass to the underlying ``scan`` helper from ``elasticsearch-py`` -
http://elasticsearch-py.readthedocs.org/en/master/helpers.html#elasticsearch.helpers.scan
"""
es = connections.get_connection(self._using)
for hit in scan(
es,
query=self.to_dict(),
index=self._index,
doc_type=self._doc_type,
**self._params
):
yield self._doc_type_map.get(hit['_type'], Result)(hit)
class MultiSearch(Request):
def __init__(self, **kwargs):
super(MultiSearch, self).__init__(**kwargs)
self._searches = []
def __getitem__(self, key):
return self._searches[key]
def __iter__(self):
return iter(self._searches)
def _clone(self):
ms = super(MultiSearch, self)._clone()
ms._searches = self._searches[:]
return ms
def add(self, search):
ms = self._clone()
ms._searches.append(search)
return ms
def to_dict(self):
out = []
for s in self._searches:
meta = {}
if s._index:
meta['index'] = s._index
if s._doc_type:
meta['type'] = s._doc_type
meta.update(s._params)
out.append(meta)
out.append(s.to_dict())
return out
def execute(self, ignore_cache=False):
if ignore_cache or not hasattr(self, '_response'):
es = connections.get_connection(self._using)
responses = es.msearch(
index=self._index,
doc_type=self._doc_type,
body=self.to_dict(),
**self._params
)
out = []
for s, r in zip(self._searches, responses['responses']):
r = Response(r, callbacks=s._doc_type_map)
r.search = s
out.append(r)
self._response = out
return self._response