func()

in pkg/client/client_v2.go [653:733]

• 61 lines of code
• 8 McCabe index (conditional complexity)

func (c *clientV2) syncUnits(expected *proto.CheckinExpected) {
	c.unitsMu.Lock()
	defer c.unitsMu.Unlock()

	if c.removeUnexpectedUnits(expected) > 0 {
		// Most state changes are reported by the unit itself via
		// Unit.UpdateState, which schedules a checkin update by calling
		// unitsStateChanged(), but removals are handled immediately
		// here so we also need to trigger the update ourselves.
		c.unitsStateChanged()
	}

	var apmConfig *proto.APMConfig
	func() {
		c.componentMu.RLock()
		defer c.componentMu.RUnlock()
		if c.componentConfig != nil {
			apmConfig = c.componentConfig.ApmConfig
		}
	}()

	for _, agentUnit := range expected.Units {
		unit := c.findUnit(agentUnit.Id, UnitType(agentUnit.Type))
		if unit == nil {
			// new unit
			unit = newUnit(
				agentUnit.Id,
				UnitType(agentUnit.Type),
				UnitState(agentUnit.State),
				UnitLogLevel(agentUnit.LogLevel),
				agentUnit.Config,
				agentUnit.ConfigStateIdx,
				expected.Features,
				apmConfig,
				c)
			c.units = append(c.units, unit)

			changed := UnitChanged{
				Type: UnitChangedAdded,
				Unit: unit,
			}

			if expected.Features != nil {
				changed.Triggers = TriggeredFeatureChange
			}

			if apmConfig != nil {
				changed.Triggers |= TriggeredAPMChange
			}

			c.changesCh <- changed
		} else {
			// existing unit
			triggers := unit.updateState(
				UnitState(agentUnit.State),
				UnitLogLevel(agentUnit.LogLevel),
				expected.FeaturesIdx,
				expected.Features,
				agentUnit.Config,
				agentUnit.ConfigStateIdx,
				apmConfig,
			)

			changed := UnitChanged{
				Triggers: triggers,
				Type:     UnitChangedModified,
				Unit:     unit,
			}

			if changed.Triggers > TriggeredNothing { // a.k.a something changed
				c.changesCh <- changed
			}
		}
	}

	// Now that we've propagated feature flags' information to units, record
	// the featuresIdx on the client so we can send it up as part of the observed
	// state in the next checkin.
	// (It's safe to write to featuresIdx here since we hold c.unitsMu.)
	c.featuresIdx = expected.FeaturesIdx
}