func()

in cmd/amazon-cloudwatch-agent-target-allocator/allocation/consistent_hashing.go [166:221]

• 42 lines of code
• 12 McCabe index (conditional complexity)

func (c *consistentHashingAllocator) SetTargets(targets map[string]*target.Item) {
	timer := prometheus.NewTimer(TimeToAssign.WithLabelValues("SetTargets", consistentHashingStrategyName))
	defer timer.ObserveDuration()

	if c.filter != nil {
		targets = c.filter.Apply(targets)
	}
	RecordTargetsKept(targets)

	c.m.Lock()
	defer c.m.Unlock()

	if len(c.collectors) == 0 {
		c.log.Info("No collector instances present, saving targets to allocate to collector(s)")
		// If there were no targets discovered previously, assign this as the new set of target items
		if len(c.targetItems) == 0 {
			c.log.Info("Not discovered any targets previously, saving targets found to the targetItems set")
			for k, item := range targets {
				c.targetItems[k] = item
			}
		} else {
			// If there were previously discovered targets, add or remove accordingly
			targetsDiffEmptyCollectorSet := diff.Maps(c.targetItems, targets)

			// Check for additions
			if len(targetsDiffEmptyCollectorSet.Additions()) > 0 {
				c.log.Info("New targets discovered, adding new targets to the targetItems set")
				for k, item := range targetsDiffEmptyCollectorSet.Additions() {
					// Do nothing if the item is already there
					if _, ok := c.targetItems[k]; ok {
						continue
					} else {
						// Add item to item pool
						c.targetItems[k] = item
					}
				}
			}

			// Check for deletions
			if len(targetsDiffEmptyCollectorSet.Removals()) > 0 {
				c.log.Info("Targets removed, Removing targets from the targetItems set")
				for k := range targetsDiffEmptyCollectorSet.Removals() {
					// Delete item from target items
					delete(c.targetItems, k)
				}
			}
		}
		return
	}
	// Check for target changes
	targetsDiff := diff.Maps(c.targetItems, targets)
	// If there are any additions or removals
	if len(targetsDiff.Additions()) != 0 || len(targetsDiff.Removals()) != 0 {
		c.handleTargets(targetsDiff)
	}
}