elasticsearch-watcher

Elasticsearch Watcher

This is an addon to the official elasticsearch python client that adds functionality for the Watcher plugin.

Installation

You can install this addon using pip::

pip install elasticsearch-watcher

Usage

You can use this client alone:

.. code:: python

from elasticsearch import Elasticsearch
from elasticsearch_watcher import WatcherClient

client = Elasticsearch()
watcher = WatcherClient(client)

watcher.get_watch(id=42)

Or you can add the watcher namespace to the official client to mimic the behaviors of other namespaces:

.. code:: python

WatcherClient.infect_client(client)

client.watcher.get_watch(id=42)

Complex example

.. code:: python

from time import sleep
from datetime import datetime
from random import randint

from elasticsearch import Elasticsearch
from elasticsearch_watcher import WatcherClient

# initialize the standard client as usual
es = Elasticsearch()
# add the .watcher namespace to it
WatcherClient.infect_client(es)

# clear the index fiorst
es.indices.delete(
    index=['alerts', 'test', '.watches', '.watch_history*'], ignore=404)

# get the watcher plugin version
print('Using watcher', es.watcher.info()['version']['number'])

# Register a new watch
es.watcher.put_watch(
    id='error_500',
    body={
        # label the watch
        'metadata': {'tags': ['errors']},

        # Run the watch every 10 seconds
        'trigger': { 'schedule': { 'interval': '10s' } },

        # Search for at least 3 documents matching the condition
        'condition': {  'script': { 'inline': 'ctx.payload.hits.total > 3' } },

        # Throttle the watch execution for 30 seconds
        'throttle_period': '30s',

        # The search request to execute
        'input':   {
            'search': {
                'request': {
                    'indices': ['test'],
                    'body': {
                        'query': {
                            'filtered': {
                                'query': { 'match': { 'status': 500 } },
                                'filter': { 'range': { 'timestamp': { 'from': '{{ctx.trigger.scheduled_time}}||-5m', 'to': '{{ctx.trigger.triggered_time}}' } } }
                            }
                        },
                        # Return statistics about different hosts
                        'aggregations': {
                            'hosts': { 'terms': { 'field': 'host' } }
                        }
        }}}},

        # The actions to perform
        'actions': {
            'send_email':    {
                'transform': {
                    # Transform the data for the template
                    'script': '''return [
                            total: ctx.payload.hits.total,
                            hosts: ctx.payload.aggregations.hosts.buckets.collect { [ host: it.key, errors: it.doc_count ] },
                            errors: ctx.payload.hits.hits.collect { it._source } 
                        ];'''
                },
                'email': {
                    'to': '[e-mail]',
                    'subject': '[ALERT] {{ctx.watch_id}}',
                    'attach_data': True,
                    'body':  '''
                        Received {{ctx.payload.total}} error documents in the last 5 minutes.

                        Hosts:

                        {{#ctx.payload.hosts}}* {{host}} ({{errors}})
                        {{/ctx.payload.hosts}}'''.replace('\n'+' '*24, '\n').strip(),
                }
            },
            'index_payload': {
                # Transform the data to be stored
                'transform': { 'script': 'return [ watch_id: ctx.watch_id, payload: ctx.payload ]' },
                'index': { 'index': 'alerts', 'doc_type': 'alert' }
            },
            'ping_webhook': {
                'webhook': {
                    'method': 'POST',
                    'host': 'localhost',
                    'port': 8000,
                    'path': '/',
                    'body': '{"watch_id" : "{{ctx.watch_id}}", "payload" : "{{ctx.payload}}"}'
                }
            }
        }
    }
)

# index documents to trigger the watch
for _ in range(5):
    es.index(
        index='test',
        doc_type='d',
        body={
            'timestamp': datetime.utcnow(),
            'status': 500,
            'host': '10.0.0.%d' % randint(1, 3)
        }
    )

# wait a bit...
for _ in range(30):
    sleep(1)
    print('.', sep='', end='', flush=True)
print()

# display information about watch execution
print('=' * 80)
s = es.search(
    index='.watch_history*',
    q='watch_id:error_500',
    sort='trigger_event.schedule.triggered_time:asc'
)
for hit in s['hits']['hits']:
    print('%s: %s' % (hit['_id'], hit['_source']['state']))

# delete the watch
es.watcher.delete_watch(id='error_500', force=True)

License

Copyright 2015 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

http://www.apache.org/licenses/LICENSE-2.0

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.