Joey Armstrong | 903c69d | 2024-02-01 19:46:39 -0500 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2018-2024 Open Networking Foundation (ONF) and the ONF Contributors |
| 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 | package kvstore |
| 17 | |
| 18 | import ( |
| 19 | "context" |
| 20 | "errors" |
| 21 | "fmt" |
| 22 | "strings" |
| 23 | "sync" |
| 24 | "time" |
| 25 | |
| 26 | "github.com/go-redis/redis/v8" |
| 27 | "github.com/opencord/voltha-lib-go/v7/pkg/log" |
| 28 | ) |
| 29 | |
| 30 | type RedisClient struct { |
| 31 | redisAPI *redis.Client |
| 32 | keyReservations map[string]time.Duration |
| 33 | watchedChannels sync.Map |
| 34 | writeLock sync.Mutex |
| 35 | keyReservationsLock sync.RWMutex |
| 36 | } |
| 37 | |
| 38 | func NewRedisClient(addr string, timeout time.Duration, useSentinel bool) (*RedisClient, error) { |
| 39 | var r *redis.Client |
| 40 | if !useSentinel { |
| 41 | r = redis.NewClient(&redis.Options{Addr: addr}) |
| 42 | } else { |
| 43 | // Redis Master-Replicas with Sentinel, sentinel masterSet config |
| 44 | // should be set to sebaRedis |
| 45 | r = redis.NewFailoverClient(&redis.FailoverOptions{ |
| 46 | MasterName: "sebaRedis", |
| 47 | SentinelAddrs: []string{addr}, |
| 48 | }) |
| 49 | } |
| 50 | |
| 51 | reservations := make(map[string]time.Duration) |
| 52 | return &RedisClient{redisAPI: r, keyReservations: reservations}, nil |
| 53 | } |
| 54 | |
| 55 | func (c *RedisClient) Get(ctx context.Context, key string) (*KVPair, error) { |
| 56 | |
| 57 | val, err := c.redisAPI.Get(ctx, key).Result() |
| 58 | valBytes, _ := ToByte(val) |
| 59 | if err != nil { |
| 60 | return nil, nil |
| 61 | } |
| 62 | return NewKVPair(key, valBytes, "", 0, 0), nil |
| 63 | } |
| 64 | |
| 65 | func (c *RedisClient) Put(ctx context.Context, key string, value interface{}) error { |
| 66 | |
| 67 | // Validate that we can convert value to a string as etcd API expects a string |
| 68 | var val string |
| 69 | var er error |
| 70 | if val, er = ToString(value); er != nil { |
| 71 | return fmt.Errorf("unexpected-type-%T", value) |
| 72 | } |
| 73 | |
| 74 | // Check if there is already a lease for this key - if there is then use it, otherwise a PUT will make |
| 75 | // that KV key permanent instead of automatically removing it after a lease expiration |
| 76 | setErr := c.redisAPI.Set(ctx, key, val, 0) |
| 77 | err := setErr.Err() |
| 78 | |
| 79 | if err != nil { |
| 80 | switch setErr.Err() { |
| 81 | case context.Canceled: |
| 82 | logger.Warnw(ctx, "context-cancelled", log.Fields{"error": err}) |
| 83 | case context.DeadlineExceeded: |
| 84 | logger.Warnw(ctx, "context-deadline-exceeded", log.Fields{"error": err}) |
| 85 | default: |
| 86 | logger.Warnw(ctx, "bad-endpoints", log.Fields{"error": err}) |
| 87 | } |
| 88 | return err |
| 89 | } |
| 90 | return nil |
| 91 | } |
| 92 | |
| 93 | func (c *RedisClient) scanAllKeysWithPrefix(ctx context.Context, key string) ([]string, error) { |
| 94 | var err error |
| 95 | allkeys := []string{} |
| 96 | cont := true |
| 97 | cursor := uint64(0) |
| 98 | matchPrefix := key + "*" |
| 99 | |
| 100 | for cont { |
| 101 | // search in the first 10000 entries starting from the point indicated by the cursor |
| 102 | logger.Debugw(ctx, "redis-scan", log.Fields{"matchPrefix": matchPrefix, "cursor": cursor}) |
| 103 | var keys []string |
| 104 | keys, cursor, err = c.redisAPI.Scan(context.Background(), cursor, matchPrefix, 10000).Result() |
| 105 | if err != nil { |
| 106 | return nil, err |
| 107 | } |
| 108 | if cursor == 0 { |
| 109 | // all data searched. break the loop |
| 110 | logger.Debugw(ctx, "redis-scan-ended", log.Fields{"matchPrefix": matchPrefix, "cursor": cursor}) |
| 111 | cont = false |
| 112 | } |
| 113 | if len(keys) == 0 { |
| 114 | // no matched data found in this cycle. Continue to search |
| 115 | logger.Debugw(ctx, "redis-scan-no-data-found-continue", log.Fields{"matchPrefix": matchPrefix, "cursor": cursor}) |
| 116 | continue |
| 117 | } |
| 118 | allkeys = append(allkeys, keys...) |
| 119 | } |
| 120 | return allkeys, nil |
| 121 | } |
| 122 | |
| 123 | func (c *RedisClient) List(ctx context.Context, key string) (map[string]*KVPair, error) { |
| 124 | var err error |
| 125 | var keys []string |
| 126 | m := make(map[string]*KVPair) |
| 127 | var values []interface{} |
| 128 | |
| 129 | if keys, err = c.scanAllKeysWithPrefix(ctx, key); err != nil { |
| 130 | return nil, err |
| 131 | } |
| 132 | |
| 133 | if len(keys) != 0 { |
| 134 | values, err = c.redisAPI.MGet(ctx, keys...).Result() |
| 135 | if err != nil { |
| 136 | return nil, err |
| 137 | } |
| 138 | } |
| 139 | for i, key := range keys { |
| 140 | if valBytes, err := ToByte(values[i]); err == nil { |
| 141 | m[key] = NewKVPair(key, interface{}(valBytes), "", 0, 0) |
| 142 | } |
| 143 | } |
| 144 | return m, nil |
| 145 | } |
| 146 | |
| 147 | func (c *RedisClient) Delete(ctx context.Context, key string) error { |
| 148 | // delete the key |
| 149 | if _, err := c.redisAPI.Del(ctx, key).Result(); err != nil { |
| 150 | logger.Errorw(ctx, "failed-to-delete-key", log.Fields{"key": key, "error": err}) |
| 151 | return err |
| 152 | } |
| 153 | logger.Debugw(ctx, "key(s)-deleted", log.Fields{"key": key}) |
| 154 | return nil |
| 155 | } |
| 156 | |
| 157 | func (c *RedisClient) DeleteWithPrefix(ctx context.Context, prefixKey string) error { |
| 158 | var keys []string |
| 159 | var err error |
| 160 | if keys, err = c.scanAllKeysWithPrefix(ctx, prefixKey); err != nil { |
| 161 | return err |
| 162 | } |
| 163 | if len(keys) == 0 { |
| 164 | logger.Warn(ctx, "nothing-to-delete-from-kv", log.Fields{"key": prefixKey}) |
| 165 | return nil |
| 166 | } |
| 167 | //call delete for keys |
| 168 | entryCount := int64(0) |
| 169 | start := 0 |
| 170 | pageSize := 5000 |
| 171 | length := len(keys) |
| 172 | for start < length { |
| 173 | end := start + pageSize |
| 174 | if end >= length { |
| 175 | end = length |
| 176 | } |
| 177 | keysToDelete := keys[start:end] |
| 178 | count := int64(0) |
| 179 | if count, err = c.redisAPI.Del(ctx, keysToDelete...).Result(); err != nil { |
| 180 | logger.Errorw(ctx, "DeleteWithPrefix method failed", log.Fields{"prefixKey": prefixKey, "numOfMatchedKeys": len(keysToDelete), "err": err}) |
| 181 | return err |
| 182 | } |
| 183 | entryCount += count |
| 184 | start = end |
| 185 | } |
| 186 | logger.Debugf(ctx, "%d entries matching with the key prefix %s have been deleted successfully", entryCount, prefixKey) |
| 187 | return nil |
| 188 | } |
| 189 | |
| 190 | func (c *RedisClient) Reserve(ctx context.Context, key string, value interface{}, ttl time.Duration) (interface{}, error) { |
| 191 | var val string |
| 192 | var er error |
| 193 | if val, er = ToString(value); er != nil { |
| 194 | return nil, fmt.Errorf("unexpected-type%T", value) |
| 195 | } |
| 196 | |
| 197 | // SetNX -- Only set the key if it does not already exist. |
| 198 | c.redisAPI.SetNX(ctx, key, value, ttl) |
| 199 | |
| 200 | // Check if set is successful |
| 201 | redisVal := c.redisAPI.Get(ctx, key).Val() |
| 202 | if redisVal == "" { |
| 203 | println("NULL") |
| 204 | return nil, nil |
| 205 | } |
| 206 | |
| 207 | if val == redisVal { |
| 208 | // set is successful, return new reservation value |
| 209 | c.keyReservationsLock.Lock() |
| 210 | c.keyReservations[key] = ttl |
| 211 | c.keyReservationsLock.Unlock() |
| 212 | bytes, _ := ToByte(val) |
| 213 | return bytes, nil |
| 214 | } else { |
| 215 | // set is not successful, return existing reservation value |
| 216 | bytes, _ := ToByte(redisVal) |
| 217 | return bytes, nil |
| 218 | } |
| 219 | |
| 220 | } |
| 221 | |
| 222 | func (c *RedisClient) ReleaseReservation(ctx context.Context, key string) error { |
| 223 | |
| 224 | redisVal := c.redisAPI.Get(ctx, key).Val() |
| 225 | if redisVal == "" { |
| 226 | return nil |
| 227 | } |
| 228 | |
| 229 | // Override SetNX value with no TTL |
| 230 | _, err := c.redisAPI.Set(ctx, key, redisVal, 0).Result() |
| 231 | if err != nil { |
| 232 | delete(c.keyReservations, key) |
| 233 | } else { |
| 234 | return err |
| 235 | } |
| 236 | return nil |
| 237 | |
| 238 | } |
| 239 | |
| 240 | func (c *RedisClient) ReleaseAllReservations(ctx context.Context) error { |
| 241 | c.writeLock.Lock() |
| 242 | defer c.writeLock.Unlock() |
| 243 | for key := range c.keyReservations { |
| 244 | err := c.ReleaseReservation(ctx, key) |
| 245 | if err != nil { |
| 246 | logger.Errorw(ctx, "cannot-release-reservation", log.Fields{"key": key, "error": err}) |
| 247 | return err |
| 248 | } |
| 249 | } |
| 250 | return nil |
| 251 | } |
| 252 | |
| 253 | func (c *RedisClient) RenewReservation(ctx context.Context, key string) error { |
| 254 | c.writeLock.Lock() |
| 255 | defer c.writeLock.Unlock() |
| 256 | |
| 257 | // Verify the key was reserved |
| 258 | ttl, ok := c.keyReservations[key] |
| 259 | if !ok { |
| 260 | return errors.New("key-not-reserved. Key not found") |
| 261 | } |
| 262 | |
| 263 | redisVal := c.redisAPI.Get(ctx, key).Val() |
| 264 | if redisVal != "" { |
| 265 | c.redisAPI.Set(ctx, key, redisVal, ttl) |
| 266 | } |
| 267 | return nil |
| 268 | } |
| 269 | |
| 270 | func (c *RedisClient) listenForKeyChange(ctx context.Context, redisCh <-chan *redis.Message, ch chan<- *Event, cancel context.CancelFunc) { |
| 271 | logger.Debug(ctx, "start-listening-on-channel ...") |
| 272 | defer cancel() |
| 273 | defer close(ch) |
| 274 | for msg := range redisCh { |
| 275 | words := strings.Split(msg.Channel, ":") |
| 276 | key := words[1] |
| 277 | msgType := getMessageType(msg.Payload) |
| 278 | var valBytes []byte |
| 279 | if msgType == PUT { |
| 280 | ev, _ := c.Get(ctx, key) |
| 281 | valBytes, _ = ToByte(ev.Value) |
| 282 | } |
| 283 | ch <- NewEvent(getMessageType(msg.Payload), []byte(key), valBytes, 0) |
| 284 | } |
| 285 | logger.Debug(ctx, "stop-listening-on-channel ...") |
| 286 | } |
| 287 | |
| 288 | func getMessageType(msg string) int { |
| 289 | isPut := strings.HasSuffix(msg, "set") |
| 290 | isDel := strings.HasSuffix(msg, "del") |
| 291 | if isPut { |
| 292 | return PUT |
| 293 | } else if isDel { |
| 294 | return DELETE |
| 295 | } else { |
| 296 | return UNKNOWN |
| 297 | } |
| 298 | } |
| 299 | |
| 300 | func (c *RedisClient) addChannelMap(key string, channelMap map[chan *Event]*redis.PubSub) []map[chan *Event]*redis.PubSub { |
| 301 | |
| 302 | var channels interface{} |
| 303 | var exists bool |
| 304 | |
| 305 | if channels, exists = c.watchedChannels.Load(key); exists { |
| 306 | channels = append(channels.([]map[chan *Event]*redis.PubSub), channelMap) |
| 307 | } else { |
| 308 | channels = []map[chan *Event]*redis.PubSub{channelMap} |
| 309 | } |
| 310 | c.watchedChannels.Store(key, channels) |
| 311 | |
| 312 | return channels.([]map[chan *Event]*redis.PubSub) |
| 313 | } |
| 314 | |
| 315 | func (c *RedisClient) removeChannelMap(key string, pos int) []map[chan *Event]*redis.PubSub { |
| 316 | var channels interface{} |
| 317 | var exists bool |
| 318 | |
| 319 | if channels, exists = c.watchedChannels.Load(key); exists { |
| 320 | channels = append(channels.([]map[chan *Event]*redis.PubSub)[:pos], channels.([]map[chan *Event]*redis.PubSub)[pos+1:]...) |
| 321 | c.watchedChannels.Store(key, channels) |
| 322 | } |
| 323 | |
| 324 | return channels.([]map[chan *Event]*redis.PubSub) |
| 325 | } |
| 326 | |
| 327 | func (c *RedisClient) getChannelMaps(key string) ([]map[chan *Event]*redis.PubSub, bool) { |
| 328 | var channels interface{} |
| 329 | var exists bool |
| 330 | |
| 331 | channels, exists = c.watchedChannels.Load(key) |
| 332 | |
| 333 | if channels == nil { |
| 334 | return nil, exists |
| 335 | } |
| 336 | |
| 337 | return channels.([]map[chan *Event]*redis.PubSub), exists |
| 338 | } |
| 339 | |
| 340 | func (c *RedisClient) Watch(ctx context.Context, key string, withPrefix bool) chan *Event { |
| 341 | |
| 342 | ctx, cancel := context.WithCancel(ctx) |
| 343 | |
| 344 | var subscribePath string |
| 345 | subscribePath = "__key*__:" + key |
| 346 | if withPrefix { |
| 347 | subscribePath += "*" |
| 348 | } |
| 349 | pubsub := c.redisAPI.PSubscribe(ctx, subscribePath) |
| 350 | redisCh := pubsub.Channel() |
| 351 | |
| 352 | // Create new channel |
| 353 | ch := make(chan *Event, maxClientChannelBufferSize) |
| 354 | |
| 355 | // Keep track of the created channels so they can be closed when required |
| 356 | channelMap := make(map[chan *Event]*redis.PubSub) |
| 357 | channelMap[ch] = pubsub |
| 358 | |
| 359 | channelMaps := c.addChannelMap(key, channelMap) |
| 360 | logger.Debugw(ctx, "watched-channels", log.Fields{"len": len(channelMaps)}) |
| 361 | |
| 362 | // Launch a go routine to listen for updates |
| 363 | go c.listenForKeyChange(ctx, redisCh, ch, cancel) |
| 364 | return ch |
| 365 | } |
| 366 | |
| 367 | func (c *RedisClient) CloseWatch(ctx context.Context, key string, ch chan *Event) { |
| 368 | // Get the array of channels mapping |
| 369 | var watchedChannels []map[chan *Event]*redis.PubSub |
| 370 | var ok bool |
| 371 | |
| 372 | if watchedChannels, ok = c.getChannelMaps(key); !ok { |
| 373 | logger.Warnw(ctx, "key-has-no-watched-channels", log.Fields{"key": key}) |
| 374 | return |
| 375 | } |
| 376 | // Look for the channels |
| 377 | var pos = -1 |
| 378 | for i, chMap := range watchedChannels { |
| 379 | if t, ok := chMap[ch]; ok { |
| 380 | logger.Debug(ctx, "channel-found") |
| 381 | // Close the Redis watcher before the client channel. This should close the etcd channel as well |
| 382 | if err := t.Close(); err != nil { |
| 383 | logger.Errorw(ctx, "watcher-cannot-be-closed", log.Fields{"key": key, "error": err}) |
| 384 | } |
| 385 | pos = i |
| 386 | break |
| 387 | } |
| 388 | } |
| 389 | |
| 390 | channelMaps, _ := c.getChannelMaps(key) |
| 391 | // Remove that entry if present |
| 392 | if pos >= 0 { |
| 393 | channelMaps = c.removeChannelMap(key, pos) |
| 394 | } |
| 395 | logger.Infow(ctx, "watcher-channel-exiting", log.Fields{"key": key, "channel": channelMaps}) |
| 396 | } |
| 397 | func (c *RedisClient) AcquireLock(ctx context.Context, lockName string, timeout time.Duration) error { |
| 398 | return nil |
| 399 | } |
| 400 | |
| 401 | func (c *RedisClient) ReleaseLock(lockName string) error { |
| 402 | return nil |
| 403 | } |
| 404 | |
| 405 | func (c *RedisClient) IsConnectionUp(ctx context.Context) bool { |
| 406 | if _, err := c.redisAPI.Set(ctx, "connection-check", "1", 0).Result(); err != nil { |
| 407 | return false |
| 408 | } |
| 409 | return true |
| 410 | |
| 411 | } |
| 412 | |
| 413 | func (c *RedisClient) Close(ctx context.Context) { |
| 414 | if err := c.redisAPI.Close(); err != nil { |
| 415 | logger.Errorw(ctx, "error-closing-client", log.Fields{"error": err}) |
| 416 | } |
| 417 | } |