// partitionReverse the graph down to a subgraph starting from the given root
func partitionReverse(g osgraph.Graph, root graph.Node, buildInputEdgeKinds []string) osgraph.Graph {
// Filter out all but BuildConfig and ImageStreamTag nodes
nodeFn := osgraph.NodesOfKind(buildgraph.BuildConfigNodeKind, imagegraph.ImageStreamTagNodeKind)
// Filter out all but BuildInputImage and BuildOutput edges
edgeKinds := []string{}
edgeKinds = append(edgeKinds, buildInputEdgeKinds...)
edgeKinds = append(edgeKinds, buildedges.BuildOutputEdgeKind)
edgeFn := osgraph.EdgesOfKind(edgeKinds...)
sub := g.Subgraph(nodeFn, edgeFn)
// Filter out inbound edges to the IST of interest
edgeFn = osgraph.RemoveOutboundEdges([]graph.Node{root})
sub = sub.Subgraph(nodeFn, edgeFn)
// Check all paths leading from the root node, collect any
// node found in them, and create the desired subgraph
desired := []graph.Node{root}
paths := path.DijkstraAllPaths(sub)
for _, node := range sub.Nodes() {
if node == root {
continue
}
path, _, _ := paths.Between(node, root)
if len(path) != 0 {
desired = append(desired, node)
}
}
return sub.SubgraphWithNodes(desired, osgraph.ExistingDirectEdge)
}
// FindCircularBuilds checks all build configs for cycles
func FindCircularBuilds(g osgraph.Graph) []osgraph.Marker {
// Filter out all but ImageStreamTag and BuildConfig nodes
nodeFn := osgraph.NodesOfKind(imagegraph.ImageStreamTagNodeKind, buildgraph.BuildConfigNodeKind)
// Filter out all but BuildInputImage and BuildOutput edges
edgeFn := osgraph.EdgesOfKind(buildedges.BuildInputImageEdgeKind, buildedges.BuildOutputEdgeKind)
// Create desired subgraph
sub := g.Subgraph(nodeFn, edgeFn)
markers := []osgraph.Marker{}
// Check for cycles
for _, cycle := range topo.CyclesIn(sub) {
nodeNames := []string{}
for _, node := range cycle {
if resourceStringer, ok := node.(osgraph.ResourceNode); ok {
nodeNames = append(nodeNames, resourceStringer.ResourceString())
}
}
markers = append(markers, osgraph.Marker{
Node: cycle[0],
RelatedNodes: cycle,
Severity: osgraph.WarningSeverity,
Key: CyclicBuildConfigWarning,
Message: fmt.Sprintf("Cycle detected in build configurations: %s", strings.Join(nodeNames, " -> ")),
})
}
return markers
}
// FindOverlappingHPAs scans the graph in search of HorizontalPodAutoscalers that are attempting to scale the same set of pods.
// This can occur in two ways:
// - 1. label selectors for two ReplicationControllers/DeploymentConfigs/etc overlap
// - 2. multiple HorizontalPodAutoscalers are attempting to scale the same ReplicationController/DeploymentConfig/etc
// Case 1 is handled by deconflicting the area of influence of ReplicationControllers/DeploymentConfigs/etc, and therefore we
// can assume that it will be handled before this step. Therefore, we are only concerned with finding HPAs that are trying to
// scale the same resources.
//
// The algorithm that is used to implement this check is described as follows:
// - create a sub-graph containing only HPA nodes and other nodes that can be scaled, as well as any scaling edges or other
// edges used to connect between objects that can be scaled
// - for every resulting edge in the new sub-graph, create an edge in the reverse direction
// - find the shortest paths between all HPA nodes in the graph
// - shortest paths connecting two horizontal pod autoscalers are used to create markers for the graph
func FindOverlappingHPAs(graph osgraph.Graph, namer osgraph.Namer) []osgraph.Marker {
markers := []osgraph.Marker{}
nodeFilter := osgraph.NodesOfKind(
kubenodes.HorizontalPodAutoscalerNodeKind,
kubenodes.ReplicationControllerNodeKind,
deploynodes.DeploymentConfigNodeKind,
)
edgeFilter := osgraph.EdgesOfKind(
kubegraph.ScalingEdgeKind,
deploygraph.DeploymentEdgeKind,
kubeedges.ManagedByControllerEdgeKind,
)
hpaSubGraph := graph.Subgraph(nodeFilter, edgeFilter)
for _, edge := range hpaSubGraph.Edges() {
osgraph.AddReversedEdge(hpaSubGraph, edge.From(), edge.To(), sets.NewString())
}
hpaNodes := hpaSubGraph.NodesByKind(kubenodes.HorizontalPodAutoscalerNodeKind)
for _, firstHPA := range hpaNodes {
// we can use Dijkstra's algorithm as we know we do not have any negative edge weights
shortestPaths := path.DijkstraFrom(firstHPA, hpaSubGraph)
for _, secondHPA := range hpaNodes {
if firstHPA == secondHPA {
continue
}
shortestPath, _ := shortestPaths.To(secondHPA)
if shortestPath == nil {
// if two HPAs have no path between them, no error exists
continue
}
markers = append(markers, osgraph.Marker{
Node: firstHPA,
Severity: osgraph.WarningSeverity,
RelatedNodes: shortestPath[1:],
Key: HPAOverlappingScaleRefWarning,
Message: fmt.Sprintf("%s and %s overlap because they both attempt to scale %s",
namer.ResourceName(firstHPA), namer.ResourceName(secondHPA), nameList(shortestPath[1:len(shortestPath)-1], namer)),
})
}
}
return markers
}
// subgraphWithoutPrunableImages creates a subgraph from g with prunable image
// nodes excluded.
func subgraphWithoutPrunableImages(g graph.Graph, prunableImageIDs graph.NodeSet) graph.Graph {
return g.Subgraph(
func(g graph.Interface, node gonum.Node) bool {
return !prunableImageIDs.Has(node.ID())
},
func(g graph.Interface, head, tail gonum.Node, edgeKinds util.StringSet) bool {
if prunableImageIDs.Has(head.ID()) {
return false
}
if prunableImageIDs.Has(tail.ID()) {
return false
}
return true
},
)
}
// subgraphWithoutPrunableImages creates a subgraph from g with prunable image
// nodes excluded.
func subgraphWithoutPrunableImages(g graph.Graph, prunableImageIDs graph.NodeSet) graph.Graph {
return g.Subgraph(
func(g graph.Interface, node gonum.Node) bool {
return !prunableImageIDs.Has(node.ID())
},
func(g graph.Interface, from, to gonum.Node, edgeKinds sets.String) bool {
if prunableImageIDs.Has(from.ID()) {
return false
}
if prunableImageIDs.Has(to.ID()) {
return false
}
return true
},
)
}
// ServiceAndDeploymentGroups breaks the provided graph of API relationships into ServiceGroup objects,
// ordered consistently. Groups are organized so that overlapping Services and DeploymentConfigs are
// part of the same group, Deployment Configs are each in their own group, and then BuildConfigs are
// part of the last service group.
func ServiceAndDeploymentGroups(g osgraph.Graph) []ServiceGroup {
deploys, covered := DeploymentPipelines(g)
other := g.Subgraph(UncoveredDeploymentFlowNodes(covered), UncoveredDeploymentFlowEdges(covered))
components := search.Tarjan(other)
serviceGroups := []ServiceGroup{}
for _, c := range components {
group := ServiceGroup{}
matches := osgraph.NodesByKind(other, c, kubegraph.ServiceNodeKind, deploygraph.DeploymentConfigNodeKind)
svcs, dcs, _ := matches[0], matches[1], matches[2]
for _, n := range svcs {
coveredDCs := []*deploygraph.DeploymentConfigNode{}
coveredRCs := []*kubegraph.ReplicationControllerNode{}
coveredPods := []*kubegraph.PodNode{}
for _, neighbor := range other.Neighbors(n) {
switch other.EdgeKind(g.EdgeBetween(neighbor, n)) {
case kubeedges.ExposedThroughServiceEdgeKind:
containerNode := osgraph.GetTopLevelContainerNode(g, neighbor)
switch castCoveredNode := containerNode.(type) {
case *deploygraph.DeploymentConfigNode:
coveredDCs = append(coveredDCs, castCoveredNode)
case *kubegraph.ReplicationControllerNode:
coveredRCs = append(coveredRCs, castCoveredNode)
case *kubegraph.PodNode:
coveredPods = append(coveredPods, castCoveredNode)
}
}
}
group.Services = append(group.Services, ServiceReference{
Service: n.(*kubegraph.ServiceNode),
CoveredDCs: coveredDCs,
CoveredRCs: coveredRCs,
CoveredPods: coveredPods,
})
}
sort.Sort(SortedServiceReferences(group.Services))
for _, n := range dcs {
d := n.(*deploygraph.DeploymentConfigNode)
group.Deployments = append(group.Deployments, DeploymentFlow{
Deployment: d,
Images: deploys[d],
})
}
sort.Sort(SortedDeploymentPipelines(group.Deployments))
if len(dcs) == 0 || len(svcs) == 0 {
unknown := g.SubgraphWithNodes(c, osgraph.ExistingDirectEdge)
for _, n := range unknown.NodeList() {
g.PredecessorEdges(n, osgraph.AddGraphEdgesTo(unknown), buildedges.BuildOutputEdgeKind)
}
unknown = unknown.EdgeSubgraph(osgraph.ReverseGraphEdge)
for _, n := range unknown.RootNodes() {
if flow, ok := ImagePipelineFromNode(unknown, n, make(osgraph.NodeSet)); ok {
group.Builds = append(group.Builds, flow)
}
}
}
sort.Sort(SortedImagePipelines(group.Builds))
serviceGroups = append(serviceGroups, group)
}
sort.Sort(SortedServiceGroups(serviceGroups))
return serviceGroups
}