Python Elasticsearch Client¶
Official low-level client for Elasticsearch. Its goal is to provide common ground for all Elasticsearch-related code in Python; because of this it tries to be opinion-free and very extendable.
For a more high level client library with more limited scope, have a look at
elasticsearch-dsl - it is a more pythonic library sitting on top of
elasticsearch-py
.
Compatibility¶
The library is compatible with all Elasticsearch versions since 0.90.x
but you
have to use a matching major version:
For Elasticsearch 2.0 and later, use the major version 1 (1.x.y
) of the
library.
For Elasticsearch 1.0 and later, use the major version 1 (1.x.y
) of the
library.
For Elasticsearch 0.90.x, use a version from 0.4.x
releases of the
library.
The recommended way to set your requirements in your setup.py or requirements.txt is:
# Elasticsearch 2.x
elasticsearch>=2.0.0,<3.0.0
# Elasticsearch 1.x
elasticsearch>=1.0.0,<2.0.0
# Elasticsearch 0.90.x
elasticsearch<1.0.0
The development is happening on master
and 1.x
branches, respectively.
Example Usage¶
from datetime import datetime
from elasticsearch import Elasticsearch
es = Elasticsearch()
doc = {
'author': 'kimchy',
'text': 'Elasticsearch: cool. bonsai cool.',
'timestamp': datetime.now(),
}
res = es.index(index="test-index", doc_type='tweet', id=1, body=doc)
print(res['created'])
res = es.get(index="test-index", doc_type='tweet', id=1)
print(res['_source'])
es.indices.refresh(index="test-index")
res = es.search(index="test-index", body={"query": {"match_all": {}}})
print("Got %d Hits:" % res['hits']['total'])
for hit in res['hits']['hits']:
print("%(timestamp)s %(author)s: %(text)s" % hit["_source"])
Features¶
This client was designed as very thin wrapper around Elasticseach’s REST API to allow for maximum flexibility. This means that there are no opinions in this client; it also means that some of the APIs are a little cumbersome to use from Python. We have created some Helpers to help with this issue.
Persistent Connections¶
elasticsearch-py
uses persistent connections inside of individual connection
pools (one per each configured or sniffed node). Out of the box you can choose
to use http
, thrift
or an experimental memcached
protocol to
communicate with the elasticsearch nodes. See Transport classes for more
information.
The transport layer will create an instance of the selected connection class
per node and keep track of the health of individual nodes - if a node becomes
unresponsive (throwing exceptions while connecting to it) it’s put on a timeout
by the ConnectionPool
class and only returned to the
circulation after the timeout is over (or when no live nodes are left). By
default nodes are randomized before being passed into the pool and round-robin
strategy is used for load balancing.
You can customize this behavior by passing parameters to the
Connection Layer API (all keyword arguments to the
Elasticsearch
class will be passed through). If what
you want to accomplish is not supported you should be able to create a subclass
of the relevant component and pass it in as a parameter to be used instead of
the default implementation.
Note
Since we use persistent connections throughout the client it means that the
client doesn’t tolerate fork
very well. If your application calls for
multiple processes make sure you create a fresh client after call to
fork
.
Automatic Retries¶
If a connection to a node fails due to connection issues (raises
ConnectionError
) it is considered in faulty state. It
will be placed on hold for dead_timeout
seconds and the request will be
retried on another node. If a connection fails multiple times in a row the
timeout will get progressively larger to avoid hitting a node that’s, by all
indication, down. If no live connection is availible, the connection that has
the smallest timeout will be used.
By default retries are not triggered by a timeout
(ConnectionTimeout
), set retry_on_timeout
to
True
to also retry on timeouts.
Sniffing¶
The client can be configured to inspect the cluster state to get a list of
nodes upon startup, periodically and/or on failure. See
Transport
parameters for details.
Some example configurations:
from elasticsearch import Elasticsearch
# by default we don't sniff, ever
es = Elasticsearch()
# you can specify to sniff on startup to inspect the cluster and load
# balance across all nodes
es = Elasticsearch(["seed1", "seed2"], sniff_on_start=True)
# you can also sniff periodically and/or after failure:
es = Elasticsearch(["seed1", "seed2"], sniff_on_start=True, sniff_on_connection_fail=True, sniffer_timeout=60)
SSL and Authentication¶
You can configure the client to use SSL
for connecting to your
elasticsearch cluster, including certificate verification and http auth:
from elasticsearch import Elasticsearch
# you can use RFC-1738 to specify the url
es = Elasticsearch(['https://user:secret@localhost:443'])
# ... or specify common parameters as kwargs
# use certifi for CA certificates
import certifi
es = Elasticsearch(
['localhost', 'otherhost'],
http_auth=('user', 'secret'),
port=443,
use_ssl=True,
verify_certs=True,
ca_certs=certifi.where(),
)
Warning
By default SSL certificates won’t be verified, pass in
verify_certs=True
to make sure your certificates will get verified. The
client doesn’t ship with any CA certificates; easiest way to obtain the
common set is by using the certifi package (as shown above).
See class Urllib3HttpConnection
for detailed
description of the options.
Logging¶
elasticsearch-py
uses the standard logging library from python to define
two loggers: elasticsearch
and elasticsearch.trace
. elasticsearch
is used by the client to log standard activity, depending on the log level.
elasticsearch.trace
can be used to log requests to the server in the form
of curl
commands using pretty-printed json that can then be executed from
command line. If the trace logger has not been configured already it is set to
propagate=False so it needs to be activated separately.
Environment considerations¶
When using the client there are several limitations of your environment that could come into play.
When using an http load balancer you cannot use the Sniffing functionality - the cluster would supply the client with IP addresses to directly cnnect to the cluster, circumventing the load balancer. Depending on your configuration this might be something you don’t want or break completely.
In some environments (notably on Google App Engine) your http requests might be
restricted so that GET
requests won’t accept body. In that case use the
send_get_body_as
parameter of Transport
to send all
bodies via post:
from elasticsearch import Elasticsearch
es = Elasticsearch(send_get_body_as='POST')
License¶
Copyright 2013 Elasticsearch
Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.