package client import ( "context" "sort" "time" "git.frostfs.info/TrueCloudLab/frostfs-node/internal/logs" "go.uber.org/zap" ) // Endpoint represents morph endpoint together with its priority. type Endpoint struct { Address string Priority int } type endpoints struct { curr int list []Endpoint } func (e *endpoints) init(ee []Endpoint) { sort.SliceStable(ee, func(i, j int) bool { return ee[i].Priority < ee[j].Priority }) e.curr = 0 e.list = ee } // SwitchRPC performs reconnection and returns true if it was successful. func (c *Client) SwitchRPC(ctx context.Context) bool { c.switchLock.Lock() defer c.switchLock.Unlock() c.client.Close() // Iterate endpoints in the order of decreasing priority. for c.endpoints.curr = range c.endpoints.list { newEndpoint := c.endpoints.list[c.endpoints.curr].Address cli, act, err := c.newCli(ctx, newEndpoint) if err != nil { c.logger.Warn(logs.ClientCouldNotEstablishConnectionToTheSwitchedRPCNode, zap.String("endpoint", newEndpoint), zap.Error(err), ) continue } c.cache.invalidate() c.logger.Info(logs.ClientConnectionToTheNewRPCNodeHasBeenEstablished, zap.String("endpoint", newEndpoint)) c.client = cli c.setActor(act) if c.cfg.switchInterval != 0 && !c.switchIsActive.Load() && c.endpoints.list[c.endpoints.curr].Priority != c.endpoints.list[0].Priority { c.switchIsActive.Store(true) go c.switchToMostPrioritized(ctx) } return true } c.inactive = true if c.cfg.inactiveModeCb != nil { c.cfg.inactiveModeCb() } return false } func (c *Client) closeWaiter(ctx context.Context) { select { case <-ctx.Done(): case <-c.closeChan: } _ = c.UnsubscribeAll() c.close() } func (c *Client) switchToMostPrioritized(ctx context.Context) { t := time.NewTicker(c.cfg.switchInterval) defer t.Stop() defer c.switchIsActive.Store(false) mainLoop: for { select { case <-ctx.Done(): return case <-t.C: c.switchLock.RLock() endpointsCopy := make([]Endpoint, len(c.endpoints.list)) copy(endpointsCopy, c.endpoints.list) currPriority := c.endpoints.list[c.endpoints.curr].Priority highestPriority := c.endpoints.list[0].Priority c.switchLock.RUnlock() if currPriority == highestPriority { // already connected to // the most prioritized return } for i, e := range endpointsCopy { if currPriority == e.Priority { // a switch will not increase the priority continue mainLoop } tryE := e.Address cli, act, err := c.newCli(ctx, tryE) if err != nil { c.logger.Warn(logs.ClientCouldNotCreateClientToTheHigherPriorityNode, zap.String("endpoint", tryE), zap.Error(err), ) continue } c.switchLock.Lock() // higher priority node could have been // connected in the other goroutine if e.Priority >= c.endpoints.list[c.endpoints.curr].Priority { cli.Close() c.switchLock.Unlock() return } c.client.Close() c.cache.invalidate() c.client = cli c.setActor(act) c.endpoints.curr = i c.switchLock.Unlock() c.logger.Info(logs.ClientSwitchedToTheHigherPriorityRPC, zap.String("endpoint", tryE)) return } } } } // close closes notification channel and wrapped WS client. func (c *Client) close() { c.switchLock.RLock() defer c.switchLock.RUnlock() c.client.Close() }