examples/failover.py

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# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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
#
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from pyignite import Client
from pyignite.datatypes.cache_config import CacheMode
from pyignite.datatypes.prop_codes import *
from pyignite.exceptions import SocketError


nodes = [
    ('127.0.0.1', 10800),
    ('127.0.0.1', 10801),
    ('127.0.0.1', 10802),
]

client = Client(timeout=4.0)
client.connect(nodes)
print('Connected')

my_cache = client.get_or_create_cache({
    PROP_NAME: 'my_cache',
    PROP_CACHE_MODE: CacheMode.PARTITIONED,
    PROP_BACKUPS_NUMBER: 2,
})
my_cache.put('test_key', 0)
test_value = 0

# abstract main loop
while True:
    try:
        # do the work
        test_value = my_cache.get('test_key') or 0
        my_cache.put('test_key', test_value + 1)
    except (OSError, SocketError) as e:
        # recover from error (repeat last command, check data
        # consistency or just continue − depends on the task)
        print('Error: {}'.format(e))
        print('Last value: {}'.format(test_value))
        print('Reconnecting')

# Connected
# Error: Connection broken.
# Last value: 2650
# Reconnecting
# Error: Connection broken.
# Last value: 10204
# Reconnecting
# Error: Connection broken.
# Last value: 18932
# Reconnecting
# Traceback (most recent call last):
#   ...
# pyignite.exceptions.ReconnectError: Can not reconnect: out of nodes.