// addImageStreamsToGraph adds all the streams to the graph. The most recent n
// image revisions for a tag will be preserved, where n is specified by the
// algorithm's tagRevisionsToKeep. Image revisions older than n are candidates
// for pruning. if the image stream's age is at least as old as the minimum
// threshold in algorithm. Otherwise, if the image stream is younger than the
// threshold, all image revisions for that stream are ineligible for pruning.
//
// addImageStreamsToGraph also adds references from each stream to all the
// layers it references (via each image a stream references).
func addImageStreamsToGraph(g graph.Graph, streams *imageapi.ImageStreamList, algorithm pruneAlgorithm) {
for i := range streams.Items {
stream := &streams.Items[i]
glog.V(4).Infof("Examining ImageStream %s/%s", stream.Namespace, stream.Name)
// use a weak reference for old image revisions by default
oldImageRevisionReferenceKind := graph.WeakReferencedImageGraphEdgeKind
age := util.Now().Sub(stream.CreationTimestamp.Time)
if age < algorithm.keepYoungerThan {
// stream's age is below threshold - use a strong reference for old image revisions instead
glog.V(4).Infof("Stream %s/%s is below age threshold - none of its images are eligible for pruning", stream.Namespace, stream.Name)
oldImageRevisionReferenceKind = graph.ReferencedImageGraphEdgeKind
}
glog.V(4).Infof("Adding ImageStream %s/%s to graph", stream.Namespace, stream.Name)
isNode := graph.ImageStream(g, stream)
imageStreamNode := isNode.(*graph.ImageStreamNode)
for tag, history := range stream.Status.Tags {
for i := range history.Items {
n := graph.FindImage(g, history.Items[i].Image)
if n == nil {
glog.V(1).Infof("Unable to find image %q in graph (from tag=%q, revision=%d, dockerImageReference=%s)", history.Items[i].Image, tag, i, history.Items[i].DockerImageReference)
continue
}
imageNode := n.(*graph.ImageNode)
var kind int
switch {
case i < algorithm.tagRevisionsToKeep:
kind = graph.ReferencedImageGraphEdgeKind
default:
kind = oldImageRevisionReferenceKind
}
glog.V(4).Infof("Checking for existing strong reference from stream %s/%s to image %s", stream.Namespace, stream.Name, imageNode.Image.Name)
if edge := g.EdgeBetween(imageStreamNode, imageNode); edge != nil && g.EdgeKind(edge) == graph.ReferencedImageGraphEdgeKind {
glog.V(4).Infof("Strong reference found")
continue
}
glog.V(4).Infof("Adding edge (kind=%d) from %q to %q", kind, imageStreamNode.UniqueName.UniqueName(), imageNode.UniqueName.UniqueName())
g.AddEdge(imageStreamNode, imageNode, kind)
glog.V(4).Infof("Adding stream->layer references")
// add stream -> layer references so we can prune them later
for _, s := range g.Successors(imageNode) {
if g.Kind(s) != graph.ImageLayerGraphKind {
continue
}
glog.V(4).Infof("Adding reference from stream %q to layer %q", stream.Name, s.(*graph.ImageLayerNode).Layer)
g.AddEdge(imageStreamNode, s, graph.ReferencedImageLayerGraphEdgeKind)
}
}
}
}
}
func findBuildInputs(g osgraph.Graph, n graph.Node, covered osgraph.NodeSet) (base ImageTagLocation, source SourceLocation, err error) {
// find inputs to the build
for _, input := range g.Neighbors(n) {
switch g.EdgeKind(g.EdgeBetween(n, input)) {
case buildedges.BuildInputEdgeKind:
if source != nil {
// report this as an error (unexpected duplicate source)
}
covered.Add(input.ID())
source = input.(SourceLocation)
case buildedges.BuildInputImageEdgeKind:
if base != nil {
// report this as an error (unexpected duplicate input build)
}
covered.Add(input.ID())
base = input.(ImageTagLocation)
}
}
return
}
// ImagePipelineFromNode attempts to locate a build flow from the provided node. If no such
// build flow can be located, false is returned.
func ImagePipelineFromNode(g osgraph.Graph, n graph.Node, covered osgraph.NodeSet) (ImagePipeline, bool) {
flow := ImagePipeline{}
switch node := n.(type) {
case *buildgraph.BuildConfigNode:
covered.Add(n.ID())
base, src, _ := findBuildInputs(g, n, covered)
flow.Build = node
flow.BaseImage = base
flow.Source = src
return flow, true
case ImageTagLocation:
covered.Add(n.ID())
flow.Image = node
for _, input := range g.Neighbors(n) {
switch g.EdgeKind(g.EdgeBetween(n, input)) {
case buildedges.BuildOutputEdgeKind:
covered.Add(input.ID())
build := input.(*buildgraph.BuildConfigNode)
if flow.Build != nil {
// report this as an error (unexpected duplicate input build)
}
if build.BuildConfig == nil {
// report this as as a missing build / broken link
break
}
base, src, _ := findBuildInputs(g, input, covered)
flow.Build = build
flow.BaseImage = base
flow.Source = src
}
}
return flow, true
default:
return flow, false
}
}
// DeploymentPipelines returns a map of DeploymentConfigs to the deployment flows that create them,
// extracted from the provided Graph.
func DeploymentPipelines(g osgraph.Graph) (DeploymentPipelineMap, osgraph.NodeSet) {
covered := make(osgraph.NodeSet)
g = g.EdgeSubgraph(osgraph.ReverseGraphEdge)
flows := make(DeploymentPipelineMap)
for _, node := range g.NodeList() {
switch t := node.(type) {
case *deploygraph.DeploymentConfigNode:
covered.Add(t.ID())
images := []ImagePipeline{}
for _, n := range g.Neighbors(node) {
// find incoming image edges only
switch g.EdgeKind(g.EdgeBetween(node, n)) {
case deployedges.TriggersDeploymentEdgeKind, deployedges.UsedInDeploymentEdgeKind:
if flow, ok := ImagePipelineFromNode(g, n, covered); ok {
images = append(images, flow)
}
}
}
output := []ImagePipeline{}
// ensure the list of images is ordered the same as what is in the template
if template := t.DeploymentConfig.Template.ControllerTemplate.Template; template != nil {
deployedges.EachTemplateImage(
&template.Spec,
deployedges.DeploymentConfigHasTrigger(t.DeploymentConfig),
func(image deployedges.TemplateImage, err error) {
if err != nil {
return
}
for i := range images {
switch t := images[i].Image.(type) {
case *imagegraph.ImageStreamTagNode:
if image.Ref != nil {
continue
}
from := image.From
if t.ImageStream.Name != from.Name || t.ImageStream.Namespace != from.Namespace {
continue
}
output = append(output, images[i])
return
case *imagegraph.DockerImageRepositoryNode:
if image.From != nil {
continue
}
ref1, ref2 := t.Ref.Minimal(), image.Ref.DockerClientDefaults().Minimal()
if ref1 != ref2 {
continue
}
output = append(output, images[i])
return
}
}
},
)
}
flows[t] = output
}
}
return flows, covered
}
// edgeKind returns true if the edge from "from" to "to" is of the desired kind.
func edgeKind(g graph.Graph, from, to gonum.Node, desiredKind int) bool {
edge := g.EdgeBetween(from, to)
kind := g.EdgeKind(edge)
return kind == desiredKind
}