Exemplo n.º 1
0
// steps is the ordered sequence of workflow steps to orchestrate a service instance change
func (p plan) steps() (steps []step.Step) {
	if p.newFeatures.NodeCount == 0 {
		for i := 0; i < p.clusterModel.NodeCount(); i++ {
			steps = append(steps, step.NewStepRemoveRandomNode(p.clusterModel, "", p.allCells, p.logger))
		}
		return
	}

	// we know the leader must survive because the cluster isn't being deleted
	leaderID, _ := p.patroni.ClusterLeader(p.clusterModel.InstanceID())

	addedNodes := false
	for i := 0; i < p.clusterGrowingBy(); i++ {
		steps = append(steps, step.NewStepAddNode(p.clusterModel, p.patroni, p.availableCells, p.logger))
		addedNodes = true
	}

	replicasToBeReplaced, leaderToBeReplaced := p.nodesToBeReplaced(leaderID)
	for _ = range replicasToBeReplaced {
		steps = append(steps, step.NewStepAddNode(p.clusterModel, p.patroni, p.availableCells, p.logger))
		addedNodes = true
	}
	if leaderToBeReplaced != nil {
		steps = append(steps, step.NewStepAddNode(p.clusterModel, p.patroni, p.availableCells, p.logger))
		addedNodes = true
	}

	if addedNodes {
		steps = append(steps, step.NewWaitForAllMembers(p.clusterModel, p.patroni, p.logger))
	}

	removedNodes := false
	for _, replica := range replicasToBeReplaced {
		steps = append(steps, step.NewStepRemoveNode(replica, p.clusterModel, p.allCells, p.logger))
		removedNodes = true
	}

	for i := 0; i < p.clusterShrinkingBy(); i++ {
		steps = append(steps, step.NewStepRemoveRandomNode(p.clusterModel, leaderID, p.allCells, p.logger))
		removedNodes = true
	}

	if removedNodes {
		steps = append(steps, step.NewWaitForAllMembers(p.clusterModel, p.patroni, p.logger))
	}

	if leaderToBeReplaced != nil {
		steps = append(steps, step.NewStepFailoverFrom(p.clusterModel, leaderID, p.patroni, p.logger))
		steps = append(steps, step.NewStepRemoveNode(leaderToBeReplaced, p.clusterModel, p.allCells, p.logger))
	}

	steps = append(steps, step.NewWaitForLeader(p.clusterModel, p.patroni, p.logger))

	return
}
Exemplo n.º 2
0
// steps is the ordered sequence of workflow steps to orchestrate a service instance change
func (p plan) steps() (steps []step.Step) {
	addedNodes := false
	for i := 0; i < p.clusterGrowingBy(); i++ {
		steps = append(steps, step.NewStepAddNode(p.clusterModel, p.patroni, p.availableCells, p.logger))
		addedNodes = true
	}

	nodesToBeReplaced := p.nodesToBeReplaced()
	for _ = range nodesToBeReplaced {
		steps = append(steps, step.NewStepAddNode(p.clusterModel, p.patroni, p.availableCells, p.logger))
		addedNodes = true
	}

	if addedNodes {
		steps = append(steps, step.NewWaitForAllMembers(p.clusterModel, p.patroni, p.logger))
	}

	removedNodes := false
	for _, replica := range p.replicas(nodesToBeReplaced) {
		steps = append(steps, step.NewStepRemoveNode(replica, p.clusterModel, p.allCells, p.logger))
		removedNodes = true
	}

	if leader := p.leader(nodesToBeReplaced); leader != nil {
		steps = append(steps, step.NewStepRemoveLeader(leader, p.clusterModel, p.allCells, p.logger))
		removedNodes = true
	}

	if removedNodes {
		steps = append(steps, step.NewWaitForAllMembers(p.clusterModel, p.patroni, p.logger))
	}

	for i := 0; i < p.clusterShrinkingBy(); i++ {
		steps = append(steps, step.NewStepRemoveRandomNode(p.clusterModel, p.allCells, p.logger))
	}

	if p.newFeatures.NodeCount > 0 {
		steps = append(steps, step.NewWaitForLeader(p.clusterModel, p.patroni, p.logger))
	}

	return
}