Merge pull request #3849 from weaveworks/cancel-join-result

Exit joinResults.result() if context cancelled

render/container.go

@@ -275,7 +275,7 @@ func (m containerImageRenderer) Render(ctx context.Context, rpt report.Report) N
 		id := report.MakeContainerImageNodeID(imageID)
 		ret.addChildAndChildren(n, id, report.ContainerImage)
 	}
-	return ret.result(containers)
+	return ret.result(ctx, containers)
 }
 
 func containerImageNodeID(n report.Node) string {
@@ -328,5 +328,5 @@ func (m containerHostnameRenderer) Render(ctx context.Context, rpt report.Report
 		}
 		ret.addChildAndChildren(n, id, containerHostnameTopology)
 	}
-	return ret.result(containers)
+	return ret.result(ctx, containers)
 }

render/endpoint.go

@@ -3,6 +3,8 @@ package render
 import (
 	"context"
 
+	opentracing "github.com/opentracing/opentracing-go"
+	otlog "github.com/opentracing/opentracing-go/log"
 	"github.com/weaveworks/scope/report"
 )
 
@@ -30,6 +32,8 @@ func MapEndpoints(f endpointMapFunc, topology string) Renderer {
 }
 
 func (e mapEndpoints) Render(ctx context.Context, rpt report.Report) Nodes {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "mapEndpoints.Render")
+	defer span.Finish()
 	local := LocalNetworks(rpt)
 	endpoints := SelectEndpoint.Render(ctx, rpt)
 	ret := newJoinResults(TopologySelector(e.topology).Render(ctx, rpt).Nodes)
@@ -47,5 +51,7 @@ func (e mapEndpoints) Render(ctx context.Context, rpt report.Report) Nodes {
 			ret.addChild(n, id, e.topology)
 		}
 	}
-	return ret.result(endpoints)
+	span.LogFields(otlog.Int("input.nodes", len(endpoints.Nodes)),
+		otlog.Int("ouput.nodes", len(ret.nodes)))
+	return ret.result(ctx, endpoints)
 }

render/filters.go

@@ -17,7 +17,7 @@ const (
 // in one call - useful for functions that need to consider the entire graph.
 // We should minimise the use of this renderer type, as it is very inflexible.
 type CustomRenderer struct {
-	RenderFunc func(Nodes) Nodes
+	RenderFunc func(context.Context, Nodes) Nodes
 	Renderer
 }
 
@@ -26,7 +26,7 @@ func (c CustomRenderer) Render(ctx context.Context, rpt report.Report) Nodes {
 	if ctx.Err() != nil {
 		return Nodes{}
 	}
-	return c.RenderFunc(c.Renderer.Render(ctx, rpt))
+	return c.RenderFunc(ctx, c.Renderer.Render(ctx, rpt))
 }
 
 // FilterFunc is the function type used by Filters
@@ -189,7 +189,7 @@ func filterInternetAdjacencies(nodes report.Nodes) {
 func ColorConnected(r Renderer) Renderer {
 	return CustomRenderer{
 		Renderer: r,
-		RenderFunc: func(input Nodes) Nodes {
+		RenderFunc: func(ctx context.Context, input Nodes) Nodes {
 			output := input.Copy()
 			for id := range connected(input.Nodes) {
 				output[id] = output[id].WithLatest(IsConnectedMark, mtime.Now(), "true")

render/host.go

@@ -1,6 +1,8 @@
 package render
 
 import (
+	"context"
+
 	"github.com/weaveworks/scope/report"
 )
 
@@ -25,7 +27,7 @@ var HostRenderer = MakeReduce(
 // format for a host, but without any Major or Minor labels.  It does
 // not have enough info to do that, and the resulting graph must be
 // merged with a host graph to get that info.
-func nodes2Hosts(nodes Nodes) Nodes {
+func nodes2Hosts(ctx context.Context, nodes Nodes) Nodes {
 	ret := newJoinResults(nil)
 
 	for _, n := range nodes.Nodes {
@@ -47,7 +49,7 @@ func nodes2Hosts(nodes Nodes) Nodes {
 			}
 		}
 	}
-	return ret.result(nodes)
+	return ret.result(ctx, nodes)
 }
 
 func endpoint2Host(n report.Node) string {

render/pod.go

@@ -197,5 +197,5 @@ func (m Map2Parent) Render(ctx context.Context, rpt report.Report) Nodes {
 			ret.addChildAndChildren(n, id, Pseudo)
 		}
 	}
-	return ret.result(input)
+	return ret.result(ctx, input)
 }

render/process.go

@@ -95,7 +95,7 @@ func hasMoreThanOneConnection(n report.Node, endpoints report.Nodes) bool {
 var processNameTopology = MakeGroupNodeTopology(report.Process, report.Name)
 
 // processes2Names maps process Nodes to Nodes for each process name.
-func processes2Names(processes Nodes) Nodes {
+func processes2Names(ctx context.Context, processes Nodes) Nodes {
 	ret := newJoinResults(nil)
 
 	for _, n := range processes.Nodes {
@@ -105,5 +105,5 @@ func processes2Names(processes Nodes) Nodes {
 			ret.addChildAndChildren(n, name, processNameTopology)
 		}
 	}
-	return ret.result(processes)
+	return ret.result(ctx, processes)
 }

render/render.go

@@ -133,7 +133,7 @@ func (m Map) Render(ctx context.Context, rpt report.Report) Nodes {
 	span.LogFields(otlog.Int("input.nodes", len(input.Nodes)),
 		otlog.Int("ouput.nodes", len(output.nodes)))
 
-	return output.result(input)
+	return output.result(ctx, input)
 }
 
 // Condition is a predecate over the entire report that can evaluate to true or false.
@@ -233,8 +233,11 @@ func (ret *joinResults) passThrough(n report.Node) {
 
 // Rewrite Adjacency of nodes in ret mapped from original nodes in
 // input, and return the result.
-func (ret *joinResults) result(input Nodes) Nodes {
+func (ret *joinResults) result(ctx context.Context, input Nodes) Nodes {
 	for _, n := range input.Nodes {
+		if ctx.Err() != nil { // check if cancelled
+			return Nodes{}
+		}
 		outID, ok := ret.mapped[n.ID]
 		if !ok {
 			continue