Avoid global by passing metricsGraphURL down

app/api_report_test.go

@@ -14,7 +14,7 @@ import (
 
 func topologyServer() *httptest.Server {
 	router := mux.NewRouter().SkipClean(true)
-	app.RegisterTopologyRoutes(router, app.StaticCollector(fixture.Report), map[string]bool{"foo_capability": true})
+	app.RegisterTopologyRoutes(router, app.StaticCollector(fixture.Report), map[string]bool{"foo_capability": true}, "")
 	return httptest.NewServer(router)
 }
 

app/api_topologies.go

@@ -548,17 +548,17 @@ func (r *Registry) RendererForTopology(topologyID string, values url.Values, rpt
 	return topology.renderer, nil, nil
 }
 
-type reporterHandler func(context.Context, Reporter, http.ResponseWriter, *http.Request)
+type reporterHandler func(context.Context, Reporter, string, http.ResponseWriter, *http.Request)
 
-func captureReporter(rep Reporter, f reporterHandler) CtxHandlerFunc {
+func captureReporter(rep Reporter, metricsGraphURL string, f reporterHandler) CtxHandlerFunc {
 	return func(ctx context.Context, w http.ResponseWriter, r *http.Request) {
-		f(ctx, rep, w, r)
+		f(ctx, rep, metricsGraphURL, w, r)
 	}
 }
 
-type rendererHandler func(context.Context, render.Renderer, render.Decorator, report.Report, http.ResponseWriter, *http.Request)
+type rendererHandler func(context.Context, render.Renderer, render.Decorator, report.Report, string, http.ResponseWriter, *http.Request)
 
-func (r *Registry) captureRenderer(rep Reporter, f rendererHandler) CtxHandlerFunc {
+func (r *Registry) captureRenderer(rep Reporter, metricGraphsURL string, f rendererHandler) CtxHandlerFunc {
 	return func(ctx context.Context, w http.ResponseWriter, req *http.Request) {
 		var (
 			topologyID = mux.Vars(req)["topology"]
@@ -579,6 +579,6 @@ func (r *Registry) captureRenderer(rep Reporter, f rendererHandler) CtxHandlerFu
 			respondWith(w, http.StatusInternalServerError, err)
 			return
 		}
-		f(ctx, renderer, decorator, rpt, w, req)
+		f(ctx, renderer, decorator, rpt, metricGraphsURL, w, req)
 	}
 }

app/api_topologies_test.go

@@ -183,14 +183,14 @@ func getTestContainerLabelFilterTopologySummary(t *testing.T, exclude bool) (det
 		return nil, err
 	}
 
-	return detailed.Summaries(fixture.Report, renderer.Render(fixture.Report, decorator)), nil
+	return detailed.Summaries(fixture.Report, renderer.Render(fixture.Report, decorator), ""), nil
 }
 
 func TestAPITopologyAddsKubernetes(t *testing.T) {
 	router := mux.NewRouter()
 	c := app.NewCollector(1 * time.Minute)
 	app.RegisterReportPostHandler(c, router)
-	app.RegisterTopologyRoutes(router, c, map[string]bool{"foo_capability": true})
+	app.RegisterTopologyRoutes(router, c, map[string]bool{"foo_capability": true}, "")
 	ts := httptest.NewServer(router)
 	defer ts.Close()
 

app/api_topology.go

@@ -29,14 +29,14 @@ type APINode struct {
 }
 
 // Full topology.
-func handleTopology(ctx context.Context, renderer render.Renderer, decorator render.Decorator, report report.Report, w http.ResponseWriter, r *http.Request) {
+func handleTopology(ctx context.Context, renderer render.Renderer, decorator render.Decorator, report report.Report, metricsGraphURL string, w http.ResponseWriter, r *http.Request) {
 	respondWith(w, http.StatusOK, APITopology{
-		Nodes: detailed.Summaries(report, renderer.Render(report, decorator)),
+		Nodes: detailed.Summaries(report, renderer.Render(report, decorator), metricsGraphURL),
 	})
 }
 
 // Individual nodes.
-func handleNode(ctx context.Context, renderer render.Renderer, decorator render.Decorator, report report.Report, w http.ResponseWriter, r *http.Request) {
+func handleNode(ctx context.Context, renderer render.Renderer, decorator render.Decorator, report report.Report, metricsGraphURL string, w http.ResponseWriter, r *http.Request) {
 	var (
 		vars             = mux.Vars(r)
 		topologyID       = vars["topology"]
@@ -49,13 +49,14 @@ func handleNode(ctx context.Context, renderer render.Renderer, decorator render.
 		http.NotFound(w, r)
 		return
 	}
-	respondWith(w, http.StatusOK, APINode{Node: detailed.MakeNode(topologyID, report, rendered, node)})
+	respondWith(w, http.StatusOK, APINode{Node: detailed.MakeNode(topologyID, report, rendered, node, metricsGraphURL)})
 }
 
 // Websocket for the full topology.
 func handleWebsocket(
 	ctx context.Context,
 	rep Reporter,
+	metricsGraphURL string,
 	w http.ResponseWriter,
 	r *http.Request,
 ) {
@@ -123,7 +124,7 @@ func handleWebsocket(
 			log.Errorf("Error generating report: %v", err)
 			return
 		}
-		newTopo := detailed.Summaries(report, renderer.Render(report, decorator))
+		newTopo := detailed.Summaries(report, renderer.Render(report, decorator), metricsGraphURL)
 		diff := detailed.TopoDiff(previousTopo, newTopo)
 		previousTopo = newTopo
 

app/router.go

@@ -91,23 +91,23 @@ func gzipHandler(h http.HandlerFunc) http.HandlerFunc {
 }
 
 // RegisterTopologyRoutes registers the various topology routes with a http mux.
-func RegisterTopologyRoutes(router *mux.Router, r Reporter, capabilities map[string]bool) {
+func RegisterTopologyRoutes(router *mux.Router, r Reporter, capabilities map[string]bool, metricsGraphURL string) {
 	get := router.Methods("GET").Subrouter()
 	get.HandleFunc("/api",
 		gzipHandler(requestContextDecorator(apiHandler(r, capabilities))))
 	get.HandleFunc("/api/topology",
 		gzipHandler(requestContextDecorator(topologyRegistry.makeTopologyList(r))))
 	get.
 		HandleFunc("/api/topology/{topology}",
-			gzipHandler(requestContextDecorator(topologyRegistry.captureRenderer(r, handleTopology)))).
+			gzipHandler(requestContextDecorator(topologyRegistry.captureRenderer(r, metricsGraphURL, handleTopology)))).
 		Name("api_topology_topology")
 	get.
 		HandleFunc("/api/topology/{topology}/ws",
-			requestContextDecorator(captureReporter(r, handleWebsocket))). // NB not gzip!
+			requestContextDecorator(captureReporter(r, metricsGraphURL, handleWebsocket))). // NB not gzip!
 		Name("api_topology_topology_ws")
 	get.
 		MatcherFunc(URLMatcher("/api/topology/{topology}/{id}")).HandlerFunc(
-		gzipHandler(requestContextDecorator(topologyRegistry.captureRenderer(r, handleNode)))).
+		gzipHandler(requestContextDecorator(topologyRegistry.captureRenderer(r, metricsGraphURL, handleNode)))).
 		Name("api_topology_topology_id")
 	get.HandleFunc("/api/report",
 		gzipHandler(requestContextDecorator(makeRawReportHandler(r))))

prog/app.go

@@ -28,7 +28,6 @@ import (
 	"github.com/weaveworks/scope/common/weave"
 	"github.com/weaveworks/scope/common/xfer"
 	"github.com/weaveworks/scope/probe/docker"
-	"github.com/weaveworks/scope/render/detailed"
 	"github.com/weaveworks/weave/common"
 )
 
@@ -52,7 +51,7 @@ func init() {
 }
 
 // Router creates the mux for all the various app components.
-func router(collector app.Collector, controlRouter app.ControlRouter, pipeRouter app.PipeRouter, externalUI bool, capabilities map[string]bool) http.Handler {
+func router(collector app.Collector, controlRouter app.ControlRouter, pipeRouter app.PipeRouter, externalUI bool, capabilities map[string]bool, metricsGraphURL string) http.Handler {
 	router := mux.NewRouter().SkipClean(true)
 
 	// We pull in the http.DefaultServeMux to get the pprof routes
@@ -62,7 +61,7 @@ func router(collector app.Collector, controlRouter app.ControlRouter, pipeRouter
 	app.RegisterReportPostHandler(collector, router)
 	app.RegisterControlRoutes(router, controlRouter)
 	app.RegisterPipeRoutes(router, pipeRouter)
-	app.RegisterTopologyRoutes(router, collector, capabilities)
+	app.RegisterTopologyRoutes(router, collector, capabilities, metricsGraphURL)
 
 	uiHandler := http.FileServer(GetFS(externalUI))
 	router.PathPrefix("/ui").Name("static").Handler(
@@ -225,7 +224,6 @@ func appMain(flags appFlags) {
 	setLogLevel(flags.logLevel)
 	setLogFormatter(flags.logPrefix)
 	runtime.SetBlockProfileRate(flags.blockProfileRate)
-	detailed.SetMetricsGraphURL(flags.metricsGraphURL)
 
 	defer log.Info("app exiting")
 	rand.Seed(time.Now().UnixNano())
@@ -300,7 +298,7 @@ func appMain(flags appFlags) {
 	capabilities := map[string]bool{
 		xfer.ReportPersistenceCapability: flags.s3URL != "local",
 	}
-	handler := router(collector, controlRouter, pipeRouter, flags.externalUI, capabilities)
+	handler := router(collector, controlRouter, pipeRouter, flags.externalUI, capabilities, flags.metricsGraphURL)
 	if flags.logHTTP {
 		handler = middleware.Log{
 			LogRequestHeaders: flags.logHTTPHeaders,

render/detailed/connections.go

@@ -121,13 +121,13 @@ func internetAddr(node report.Node, ep report.Node) (string, bool) {
 	return addr, true
 }
 
-func (c *connectionCounters) rows(r report.Report, ns report.Nodes, includeLocal bool) []Connection {
+func (c *connectionCounters) rows(r report.Report, ns report.Nodes, includeLocal bool, metricsGraphURL string) []Connection {
 	output := []Connection{}
 	for row, count := range c.counts {
 		// Use MakeNodeSummary to render the id and label of this node
 		// TODO(paulbellamy): Would be cleaner if we hade just a
 		// MakeNodeID(ns[row.remoteNodeID]). As we don't need the whole summary.
-		summary, _ := MakeNodeSummary(r, ns[row.remoteNodeID])
+		summary, _ := MakeNodeSummary(r, ns[row.remoteNodeID], metricsGraphURL)
 		connection := Connection{
 			ID:         fmt.Sprintf("%s-%s-%s-%s", row.remoteNodeID, row.remoteAddr, row.localAddr, row.port),
 			NodeID:     summary.ID,
@@ -162,7 +162,7 @@ func (c *connectionCounters) rows(r report.Report, ns report.Nodes, includeLocal
 	return output
 }
 
-func incomingConnectionsSummary(topologyID string, r report.Report, n report.Node, ns report.Nodes) ConnectionsSummary {
+func incomingConnectionsSummary(topologyID string, r report.Report, n report.Node, ns report.Nodes, metricsGraphURL string) ConnectionsSummary {
 	localEndpointIDs, localEndpointIDCopies := endpointChildIDsAndCopyMapOf(n)
 	counts := newConnectionCounters()
 
@@ -188,11 +188,11 @@ func incomingConnectionsSummary(topologyID string, r report.Report, n report.Nod
 		TopologyID:  topologyID,
 		Label:       "Inbound",
 		Columns:     columnHeaders,
-		Connections: counts.rows(r, ns, isInternetNode(n)),
+		Connections: counts.rows(r, ns, isInternetNode(n), metricsGraphURL),
 	}
 }
 
-func outgoingConnectionsSummary(topologyID string, r report.Report, n report.Node, ns report.Nodes) ConnectionsSummary {
+func outgoingConnectionsSummary(topologyID string, r report.Report, n report.Node, ns report.Nodes, metricsGraphURL string) ConnectionsSummary {
 	localEndpoints := endpointChildrenOf(n)
 	counts := newConnectionCounters()
 
@@ -220,7 +220,7 @@ func outgoingConnectionsSummary(topologyID string, r report.Report, n report.Nod
 		TopologyID:  topologyID,
 		Label:       "Outbound",
 		Columns:     columnHeaders,
-		Connections: counts.rows(r, ns, isInternetNode(n)),
+		Connections: counts.rows(r, ns, isInternetNode(n), metricsGraphURL),
 	}
 }
 

render/detailed/links.go

@@ -15,7 +15,7 @@ import (
 // MetricLink describes a URL referencing a metric.
 type MetricLink struct {
 	// References the metric id
-	ID       string `json:"id,omitempty"`
+	ID       string `json:"id"`
 	Label    string `json:"label"`
 	URL      string `json:"url"`
 	Priority int    `json:"priority"`
@@ -25,9 +25,6 @@ type MetricLink struct {
 const urlQueryVarName = ":query"
 
 var (
-	// As configured by the user
-	metricsGraphURL = ""
-
 	// Available metric links
 	linkTemplates = []MetricLink{
 		{ID: docker.CPUTotalUsage, Label: "CPU", Priority: 1},
@@ -105,22 +102,10 @@ var (
 	}
 )
 
-// SetMetricsGraphURL sets the URL we deduce our eventual metric link from.
-// Supports placeholders such as `:orgID` and `:query`. An empty url disables
-// this feature. If the `:query` part is missing, a JSON version will be
-// appended, see `queryParamsAsJSON()` for more info.
-func SetMetricsGraphURL(url string) {
-	metricsGraphURL = url
-}
-
 // NodeMetricLinks returns the links of a node. The links are collected
 // by a predefined set but filtered depending on whether a query
 // is configured or not for the particular topology.
 func NodeMetricLinks(_ report.Report, n report.Node) []MetricLink {
-	if metricsGraphURL == "" {
-		return nil
-	}
-
 	queries := topologyQueries[n.Topology]
 	if len(queries) == 0 {
 		return nil
@@ -137,8 +122,10 @@ func NodeMetricLinks(_ report.Report, n report.Node) []MetricLink {
 }
 
 // RenderMetricLinks executes the templated links by supplying the node summary as data.
+// `metricsGraphURL` supports placeholders such as `:orgID` and `:query`. If the `:query`
+// part is missing, a JSON version will be appended, see `queryParamsAsJSON()` for more info.
 // It returns the modified summary.
-func RenderMetricLinks(summary NodeSummary, n report.Node) NodeSummary {
+func RenderMetricLinks(summary NodeSummary, n report.Node, metricsGraphURL string) NodeSummary {
 	queries := topologyQueries[n.Topology]
 	if len(queries) == 0 || len(summary.MetricLinks) == 0 {
 		return summary
@@ -157,7 +144,7 @@ func RenderMetricLinks(summary NodeSummary, n report.Node) NodeSummary {
 			continue
 		}
 
-		link.URL = buildURL(bs.String())
+		link.URL = buildURL(bs.String(), metricsGraphURL)
 		links = append(links, link)
 	}
 	summary.MetricLinks = links
@@ -167,7 +154,7 @@ func RenderMetricLinks(summary NodeSummary, n report.Node) NodeSummary {
 
 // buildURL puts together the URL by looking at the configured
 // `metricsGraphURL`.
-func buildURL(query string) string {
+func buildURL(query, metricsGraphURL string) string {
 	if strings.Contains(metricsGraphURL, urlQueryVarName) {
 		return strings.Replace(metricsGraphURL, urlQueryVarName, url.PathEscape(query), -1)
 	}

render/detailed/links_test.go

@@ -16,21 +16,12 @@ var (
 	sampleUnknownNode = report.MakeNode("???").WithTopology("foo")
 )
 
-func TestNodeMetricLinks_DefaultDisabled(t *testing.T) {
-	links := detailed.NodeMetricLinks(sampleReport, samplePodNode)
-	assert.Nil(t, links)
-}
-
 func TestNodeMetricLinks_UnknownTopology(t *testing.T) {
-	detailed.SetMetricsGraphURL("/foo")
-
 	links := detailed.NodeMetricLinks(sampleReport, sampleUnknownNode)
 	assert.Nil(t, links)
 }
 
 func TestNodeMetricLinks(t *testing.T) {
-	detailed.SetMetricsGraphURL("/foo")
-	defer detailed.SetMetricsGraphURL("")
 	expected := []detailed.MetricLink{
 		{ID: docker.CPUTotalUsage, Label: "CPU", Priority: 1, URL: ""},
 		{ID: docker.MemoryUsage, Label: "Memory", Priority: 2, URL: ""},
@@ -43,16 +34,14 @@ func TestNodeMetricLinks(t *testing.T) {
 func TestRenderMetricLinks_UnknownTopology(t *testing.T) {
 	summary := detailed.NodeSummary{}
 
-	result := detailed.RenderMetricLinks(summary, sampleUnknownNode)
+	result := detailed.RenderMetricLinks(summary, sampleUnknownNode, "")
 	assert.Equal(t, summary, result)
 }
 
 func TestRenderMetricLinks_Pod(t *testing.T) {
-	detailed.SetMetricsGraphURL("/prom/:orgID/notebook/new")
-	defer detailed.SetMetricsGraphURL("")
 	summary := detailed.NodeSummary{Label: "woo", MetricLinks: detailed.NodeMetricLinks(sampleReport, samplePodNode)}
 
-	result := detailed.RenderMetricLinks(summary, samplePodNode)
+	result := detailed.RenderMetricLinks(summary, samplePodNode, "/prom/:orgID/notebook/new")
 	assert.Equal(t,
 		"/prom/:orgID/notebook/new/%7B%22cells%22:%5B%7B%22queries%22:%5B%22sum%28rate%28container_cpu_usage_seconds_total%7Bpod_name=%5C%22woo%5C%22%7D%5B1m%5D%29%29%22%5D%7D%5D%7D",
 		result.MetricLinks[0].URL)
@@ -62,11 +51,9 @@ func TestRenderMetricLinks_Pod(t *testing.T) {
 }
 
 func TestRenderMetricLinks_QueryReplacement(t *testing.T) {
-	detailed.SetMetricsGraphURL("/foo/:orgID/bar?q=:query")
-	defer detailed.SetMetricsGraphURL("")
 	summary := detailed.NodeSummary{Label: "boo", MetricLinks: detailed.NodeMetricLinks(sampleReport, samplePodNode)}
 
-	result := detailed.RenderMetricLinks(summary, samplePodNode)
+	result := detailed.RenderMetricLinks(summary, samplePodNode, "/foo/:orgID/bar?q=:query")
 	assert.Equal(t,
 		"/foo/:orgID/bar?q=sum%28rate%28container_cpu_usage_seconds_total%7Bpod_name=%22boo%22%7D%5B1m%5D%29%29",
 		result.MetricLinks[0].URL)

render/detailed/node.go

@@ -80,15 +80,15 @@ func (c *ControlInstance) CodecDecodeSelf(decoder *codec.Decoder) {
 
 // MakeNode transforms a renderable node to a detailed node. It uses
 // aggregate metadata, plus the set of origin node IDs, to produce tables.
-func MakeNode(topologyID string, r report.Report, ns report.Nodes, n report.Node) Node {
-	summary, _ := MakeNodeSummary(r, n)
+func MakeNode(topologyID string, r report.Report, ns report.Nodes, n report.Node, metricsGraphURL string) Node {
+	summary, _ := MakeNodeSummary(r, n, metricsGraphURL)
 	return Node{
 		NodeSummary: summary,
 		Controls:    controls(r, n),
-		Children:    children(r, n),
+		Children:    children(r, n, metricsGraphURL),
 		Connections: []ConnectionsSummary{
-			incomingConnectionsSummary(topologyID, r, n, ns),
-			outgoingConnectionsSummary(topologyID, r, n, ns),
+			incomingConnectionsSummary(topologyID, r, n, ns, metricsGraphURL),
+			outgoingConnectionsSummary(topologyID, r, n, ns, metricsGraphURL),
 		},
 	}
 }
@@ -181,13 +181,13 @@ var nodeSummaryGroupSpecs = []struct {
 	},
 }
 
-func children(r report.Report, n report.Node) []NodeSummaryGroup {
+func children(r report.Report, n report.Node, metricsGraphURL string) []NodeSummaryGroup {
 	summaries := map[string][]NodeSummary{}
 	n.Children.ForEach(func(child report.Node) {
 		if child.ID == n.ID {
 			return
 		}
-		summary, ok := MakeNodeSummary(r, child)
+		summary, ok := MakeNodeSummary(r, child, metricsGraphURL)
 		if !ok {
 			return
 		}