Initial commit moving openolt adapter from voltha-go to the new repo.
This version works with ponsim rather than openolt, this is temporary.
It is currently being fixed to work with openolt.
Change-Id: I34a800c98f050140b367e2d474b7aa8b79f34b9a
Signed-off-by: William Kurkian <wkurkian@cisco.com>
diff --git a/python/adapters/common/kvstore/kv_client.py b/python/adapters/common/kvstore/kv_client.py
new file mode 100644
index 0000000..f6486f3
--- /dev/null
+++ b/python/adapters/common/kvstore/kv_client.py
@@ -0,0 +1,206 @@
+# Copyright 2018-present Open Networking Foundation
+#
+# 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.
+
+from python.common.utils.asleep import asleep
+from structlog import get_logger
+from twisted.internet.defer import inlineCallbacks, returnValue
+
+log = get_logger()
+
+class KVPair():
+ def __init__(self, key, value, index):
+ self.key = key
+ self.value = value
+ self.index = index
+
+class Event():
+ PUT = 0
+ DELETE = 1
+ CONNECTION_DOWN = 2
+
+ def __init__(self, event_type, key, value):
+ self.event_type = event_type
+ self.key = key
+ self.value = value
+
+RETRY_BACKOFF = [0.05, 0.1, 0.2, 0.5, 1, 2, 5]
+DEFAULT_TIMEOUT = 0.0
+for i in range(len(RETRY_BACKOFF)):
+ DEFAULT_TIMEOUT += RETRY_BACKOFF[i]
+
+class KVClient():
+
+ def __init__(self, kv_host, kv_port):
+ self.host = kv_host
+ self.port = kv_port
+ self.key_reservations = {}
+ self.key_watches = {}
+ self.retries = 0
+ self.retry_time = 0
+
+ @inlineCallbacks
+ def get(self, key, timeout=DEFAULT_TIMEOUT):
+ '''
+ This method returns the value of the given key in KV store.
+
+ :param key: The key whose value is requested
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: (KVPair, error) where KVPair is None if an error occurred
+ '''
+ result = yield self._op_with_retry('GET', key, None, timeout)
+ returnValue(result)
+
+ @inlineCallbacks
+ def list(self, key, timeout=DEFAULT_TIMEOUT):
+ '''
+ The list method returns an array of key-value pairs all of which
+ share the same key prefix.
+
+ :param key: The key prefix
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: ([]KVPair, error) where []KVPair is a list of KVPair objects
+ '''
+ result = yield self._op_with_retry('LIST', key, None, timeout)
+ returnValue(result)
+
+ @inlineCallbacks
+ def put(self, key, value, timeout=DEFAULT_TIMEOUT):
+ '''
+ The put method writes a value to the given key in KV store.
+ Do NOT modify a reserved key in an etcd store; doing so seems
+ to nullify the TTL of the key. In other words, the key lasts
+ forever.
+
+ :param key: The key to be written to
+ :param value: The value of the key
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: error, which is set to None for a successful write
+ '''
+ _, err = yield self._op_with_retry('PUT', key, value, timeout)
+ returnValue(err)
+
+ @inlineCallbacks
+ def delete(self, key, timeout=DEFAULT_TIMEOUT):
+ '''
+ The delete method removes a key from the KV store.
+
+ :param key: The key to be deleted
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: error, which is set to None for a successful deletion
+ '''
+ _, err = yield self._op_with_retry('DELETE', key, None, timeout)
+ returnValue(err)
+
+ @inlineCallbacks
+ def reserve(self, key, value, ttl, timeout=DEFAULT_TIMEOUT):
+ '''
+ This method acts essentially like a semaphore. The underlying mechanism
+ differs depending on the KV store: etcd uses a test-and-set transaction;
+ consul uses an acquire lock. If using etcd, do NOT write to the key
+ subsequent to the initial reservation; the TTL functionality may become
+ impaired (i.e. the reservation never expires).
+
+ :param key: The key under reservation
+ :param value: The reservation owner
+ :param ttl: The time-to-live (TTL) for the reservation. The key is unreserved
+ by the KV store when the TTL expires.
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: (key_value, error) If the key is acquired, then the value returned will
+ be the value passed in. If the key is already acquired, then the value assigned
+ to that key will be returned.
+ '''
+ result = yield self._op_with_retry('RESERVE', key, value, timeout, ttl=ttl)
+ returnValue(result)
+
+ @inlineCallbacks
+ def renew_reservation(self, key, timeout=DEFAULT_TIMEOUT):
+ '''
+ This method renews the reservation for a given key. A reservation expires
+ after the TTL (Time To Live) period specified when reserving the key.
+
+ :param key: The reserved key
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: error, which is set to None for a successful renewal
+ '''
+ result, err = yield self._op_with_retry('RENEW', key, None, timeout)
+ returnValue(err)
+
+ @inlineCallbacks
+ def release_reservation(self, key, timeout=DEFAULT_TIMEOUT):
+ '''
+ The release_reservation method cancels the reservation for a given key.
+
+ :param key: The reserved key
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: error, which is set to None for a successful cancellation
+ '''
+ result, err = yield self._op_with_retry('RELEASE', key, None, timeout)
+ returnValue(err)
+
+ @inlineCallbacks
+ def release_all_reservations(self, timeout=DEFAULT_TIMEOUT):
+ '''
+ This method cancels all key reservations made previously
+ using the reserve API.
+
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: error, which is set to None for a successful cancellation
+ '''
+ result, err = yield self._op_with_retry('RELEASE-ALL', None, None, timeout)
+ returnValue(err)
+
+ @inlineCallbacks
+ def watch(self, key, key_change_callback, timeout=DEFAULT_TIMEOUT):
+ '''
+ This method provides a watch capability for the given key. If the value of the key
+ changes or the key is deleted, then an event indicating the change is passed to
+ the given callback function.
+
+ :param key: The key to be watched
+ :param key_change_callback: The function invoked whenever the key changes
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: There is no return; key change events are passed to the callback function
+ '''
+ raise NotImplementedError('Method not implemented')
+
+ @inlineCallbacks
+ def close_watch(self, key, timeout=DEFAULT_TIMEOUT):
+ '''
+ This method closes the watch on the given key. Once the watch is closed, key
+ change events are no longer passed to the key change callback function.
+
+ :param key: The key under watch
+ :param timeout: The length of time in seconds the method will wait for a response
+ :return: There is no return
+ '''
+ raise NotImplementedError('Method not implemented')
+
+ @inlineCallbacks
+ def _op_with_retry(self, operation, key, value, timeout, *args, **kw):
+ raise NotImplementedError('Method not implemented')
+
+ def _backoff(self, msg):
+ wait_time = RETRY_BACKOFF[min(self.retries, len(RETRY_BACKOFF) - 1)]
+ self.retry_time += wait_time
+ self.retries += 1
+ log.error(msg, next_retry_in_secs=wait_time,
+ total_delay_in_secs = self.retry_time,
+ retries=self.retries)
+ return asleep(wait_time)
+
+ def _clear_backoff(self):
+ if self.retries:
+ log.debug('reset-backoff', after_retries=self.retries)
+ self.retries = 0
+ self.retry_time = 0
\ No newline at end of file