Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 1 | # |
Zsolt Haraszti | 3eb27a5 | 2017-01-03 21:56:48 -0800 | [diff] [blame] | 2 | # Copyright 2017 the original author or authors. |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 3 | # |
| 4 | # Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | # you may not use this file except in compliance with the License. |
| 6 | # You may obtain a copy of the License at |
| 7 | # |
| 8 | # http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | # |
| 10 | # Unless required by applicable law or agreed to in writing, software |
| 11 | # distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | # See the License for the specific language governing permissions and |
| 14 | # limitations under the License. |
| 15 | # |
| 16 | from uuid import uuid4 |
| 17 | |
| 18 | import structlog |
Zsolt Haraszti | b706784 | 2016-11-22 18:11:53 -0800 | [diff] [blame] | 19 | from simplejson import dumps, loads |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 20 | |
Zsolt Haraszti | 00d9a84 | 2016-11-23 11:18:23 -0800 | [diff] [blame] | 21 | from voltha.core.config.config_node import ConfigNode |
Zsolt Haraszti | b706784 | 2016-11-22 18:11:53 -0800 | [diff] [blame] | 22 | from voltha.core.config.config_rev import ConfigRevision |
| 23 | from voltha.core.config.config_rev_persisted import PersistedConfigRevision |
Zsolt Haraszti | 00d9a84 | 2016-11-23 11:18:23 -0800 | [diff] [blame] | 24 | from voltha.core.config.merge_3way import MergeConflictException |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 25 | |
| 26 | log = structlog.get_logger() |
| 27 | |
| 28 | |
| 29 | class ConfigRoot(ConfigNode): |
| 30 | |
| 31 | __slots__ = ( |
| 32 | '_dirty_nodes', # holds set of modified nodes per transaction branch |
Zsolt Haraszti | b706784 | 2016-11-22 18:11:53 -0800 | [diff] [blame] | 33 | '_kv_store', |
| 34 | '_loading', |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 35 | '_rev_cls', |
Khen Nursimulu | 56b3647 | 2017-03-08 15:32:42 -0500 | [diff] [blame] | 36 | '_deferred_callback_queue', |
| 37 | '_notification_deferred_callback_queue' |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 38 | ) |
| 39 | |
Zsolt Haraszti | b706784 | 2016-11-22 18:11:53 -0800 | [diff] [blame] | 40 | def __init__(self, initial_data, kv_store=None, rev_cls=ConfigRevision): |
| 41 | self._kv_store = kv_store |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 42 | self._dirty_nodes = {} |
Zsolt Haraszti | b706784 | 2016-11-22 18:11:53 -0800 | [diff] [blame] | 43 | self._loading = False |
| 44 | if kv_store is not None and \ |
| 45 | not issubclass(rev_cls, PersistedConfigRevision): |
| 46 | rev_cls = PersistedConfigRevision |
| 47 | self._rev_cls = rev_cls |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 48 | self._deferred_callback_queue = [] |
Khen Nursimulu | 56b3647 | 2017-03-08 15:32:42 -0500 | [diff] [blame] | 49 | self._notification_deferred_callback_queue = [] |
Zsolt Haraszti | b706784 | 2016-11-22 18:11:53 -0800 | [diff] [blame] | 50 | super(ConfigRoot, self).__init__(self, initial_data, False) |
| 51 | |
| 52 | @property |
| 53 | def kv_store(self): |
| 54 | if self._loading: |
| 55 | # provide fake store for storing things |
| 56 | # TODO this shall be a fake_dict providing noop for all relevant |
| 57 | # operations |
| 58 | return dict() |
| 59 | else: |
| 60 | return self._kv_store |
| 61 | |
| 62 | def mkrev(self, *args, **kw): |
| 63 | return self._rev_cls(*args, **kw) |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 64 | |
| 65 | def mk_txbranch(self): |
| 66 | txid = uuid4().hex[:12] |
| 67 | self._dirty_nodes[txid] = {self} |
| 68 | self._mk_txbranch(txid) |
| 69 | return txid |
| 70 | |
| 71 | def del_txbranch(self, txid): |
| 72 | for dirty_node in self._dirty_nodes[txid]: |
| 73 | dirty_node._del_txbranch(txid) |
| 74 | del self._dirty_nodes[txid] |
| 75 | |
| 76 | def fold_txbranch(self, txid): |
| 77 | try: |
| 78 | self._merge_txbranch(txid, dry_run=1) |
| 79 | except MergeConflictException: |
| 80 | self.del_txbranch(txid) |
| 81 | raise |
| 82 | |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 83 | try: |
| 84 | self._merge_txbranch(txid) |
| 85 | finally: |
| 86 | self.execute_deferred_callbacks() |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 87 | |
| 88 | # ~~~~~~ Overridden, root-level CRUD methods to handle transactions ~~~~~~~ |
| 89 | |
| 90 | def update(self, path, data, strict=None, txid=None, mk_branch=None): |
| 91 | assert mk_branch is None |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 92 | self.check_callback_queue() |
| 93 | try: |
| 94 | if txid is not None: |
| 95 | dirtied = self._dirty_nodes[txid] |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 96 | |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 97 | def track_dirty(node): |
| 98 | dirtied.add(node) |
| 99 | return node._mk_txbranch(txid) |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 100 | |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 101 | res = super(ConfigRoot, self).update(path, data, strict, |
| 102 | txid, track_dirty) |
| 103 | else: |
| 104 | res = super(ConfigRoot, self).update(path, data, strict) |
| 105 | finally: |
| 106 | self.execute_deferred_callbacks() |
| 107 | return res |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 108 | |
| 109 | def add(self, path, data, txid=None, mk_branch=None): |
| 110 | assert mk_branch is None |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 111 | self.check_callback_queue() |
| 112 | try: |
| 113 | if txid is not None: |
| 114 | dirtied = self._dirty_nodes[txid] |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 115 | |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 116 | def track_dirty(node): |
| 117 | dirtied.add(node) |
| 118 | return node._mk_txbranch(txid) |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 119 | |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 120 | res = super(ConfigRoot, self).add(path, data, txid, track_dirty) |
| 121 | else: |
| 122 | res = super(ConfigRoot, self).add(path, data) |
| 123 | finally: |
| 124 | self.execute_deferred_callbacks() |
| 125 | return res |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 126 | |
| 127 | def remove(self, path, txid=None, mk_branch=None): |
| 128 | assert mk_branch is None |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 129 | self.check_callback_queue() |
| 130 | try: |
| 131 | if txid is not None: |
| 132 | dirtied = self._dirty_nodes[txid] |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 133 | |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 134 | def track_dirty(node): |
| 135 | dirtied.add(node) |
| 136 | return node._mk_txbranch(txid) |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 137 | |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 138 | res = super(ConfigRoot, self).remove(path, txid, track_dirty) |
| 139 | else: |
| 140 | res = super(ConfigRoot, self).remove(path) |
| 141 | finally: |
| 142 | self.execute_deferred_callbacks() |
| 143 | return res |
| 144 | |
| 145 | def check_callback_queue(self): |
| 146 | assert len(self._deferred_callback_queue) == 0 |
| 147 | |
| 148 | def enqueue_callback(self, func, *args, **kw): |
| 149 | self._deferred_callback_queue.append((func, args, kw)) |
| 150 | |
Khen Nursimulu | 56b3647 | 2017-03-08 15:32:42 -0500 | [diff] [blame] | 151 | def enqueue_notification_callback(self, func, *args, **kw): |
| 152 | """ |
| 153 | A separate queue is required for notification. Previously, when the |
| 154 | notifications were added to the self._deferred_callback_queue there |
| 155 | was a deadlock condition where two callbacks were added (one |
| 156 | related to the model change and one for the notification related to |
| 157 | that model change). Since the model change requires the |
| 158 | self._deferred_callback_queue to be empty then there was a deadlock |
| 159 | in that scenario. The simple approach to avoid this problem is to |
| 160 | have separate queues for model and notification. |
| 161 | TODO: Investigate whether there is a need for the |
| 162 | self._deferred_callback_queue to handle multiple model events at the same time |
| 163 | :param func: callback function |
| 164 | :param args: args |
| 165 | :param kw: key-value args |
| 166 | :return: None |
| 167 | """ |
| 168 | self._notification_deferred_callback_queue.append((func, args, kw)) |
| 169 | |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 170 | def execute_deferred_callbacks(self): |
Khen Nursimulu | 56b3647 | 2017-03-08 15:32:42 -0500 | [diff] [blame] | 171 | # First process the model-triggered related callbacks |
Zsolt Haraszti | 6686203 | 2016-11-28 14:28:39 -0800 | [diff] [blame] | 172 | while self._deferred_callback_queue: |
| 173 | func, args, kw = self._deferred_callback_queue.pop(0) |
| 174 | func(*args, **kw) |
Zsolt Haraszti | dafefe1 | 2016-11-14 21:29:58 -0800 | [diff] [blame] | 175 | |
Khen Nursimulu | 56b3647 | 2017-03-08 15:32:42 -0500 | [diff] [blame] | 176 | # Execute the notification callbacks |
| 177 | while self._notification_deferred_callback_queue: |
| 178 | func, args, kw = self._notification_deferred_callback_queue.pop(0) |
| 179 | func(*args, **kw) |
| 180 | |
| 181 | |
Zsolt Haraszti | b706784 | 2016-11-22 18:11:53 -0800 | [diff] [blame] | 182 | # ~~~~~~~~~~~~~~~~ Persistence related ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 183 | |
| 184 | @classmethod |
| 185 | def load(cls, root_msg_cls, kv_store): |
| 186 | # need to use fake kv store during initial load for not to override |
| 187 | # our real k vstore |
| 188 | fake_kv_store = dict() # shall use more efficient mock dict |
| 189 | root = cls(root_msg_cls(), kv_store=fake_kv_store, |
| 190 | rev_cls=PersistedConfigRevision) |
| 191 | # we can install the real store now |
| 192 | root._kv_store = kv_store |
| 193 | root.load_from_persistence(root_msg_cls) |
| 194 | return root |
| 195 | |
| 196 | def _make_latest(self, branch, *args, **kw): |
| 197 | super(ConfigRoot, self)._make_latest(branch, *args, **kw) |
| 198 | # only persist the committed branch |
| 199 | if self._kv_store is not None and branch._txid is None: |
| 200 | root_data = dict( |
| 201 | latest=branch._latest._hash, |
| 202 | tags=dict((k, v._hash) for k, v in self._tags.iteritems()) |
| 203 | ) |
| 204 | blob = dumps(root_data) |
| 205 | self._kv_store['root'] = blob |
| 206 | |
Ryan Van Gilder | bf974d0 | 2017-02-24 15:01:22 -0800 | [diff] [blame] | 207 | def persist_tags(self): |
| 208 | if self._kv_store is not None: |
| 209 | root_data = loads(self.kv_store['root']) |
| 210 | root_data = dict( |
| 211 | latest=root_data['latest'], |
| 212 | tags=dict((k, v._hash) for k, v in self._tags.iteritems()) |
| 213 | ) |
| 214 | blob = dumps(root_data) |
| 215 | self._kv_store['root'] = blob |
| 216 | |
Zsolt Haraszti | b706784 | 2016-11-22 18:11:53 -0800 | [diff] [blame] | 217 | def load_from_persistence(self, root_msg_cls): |
| 218 | self._loading = True |
| 219 | blob = self._kv_store['root'] |
| 220 | root_data = loads(blob) |
| 221 | |
| 222 | for tag, hash in root_data['tags'].iteritems(): |
Ryan Van Gilder | bf974d0 | 2017-02-24 15:01:22 -0800 | [diff] [blame] | 223 | self.load_latest(hash) |
| 224 | self._tags[tag] = self.latest |
Zsolt Haraszti | b706784 | 2016-11-22 18:11:53 -0800 | [diff] [blame] | 225 | |
| 226 | self.load_latest(root_data['latest']) |
| 227 | |
| 228 | self._loading = False |
| 229 | |