Append links directly to metrics

The initial idea was to keep it separate since the unattached links were also to be displayed distinctively from the metrics. With the new design, unattached links are rendered in the same list as metrics with attached links. Therefore, we treat unattached metric links as an empty metric.
2026-07-28 17:51:21 +00:00 · 2017-07-19 11:01:47 +02:00
parent b8c75071fe
commit 8188b7aed2
23 changed files with 518 additions and 290 deletions
--- a/render/detailed/links.go
+++ b/render/detailed/links.go
@@ -12,46 +12,70 @@ import (
 	"github.com/ugorji/go/codec"
 )

-// MetricLink describes a URL referencing a metric.
-type MetricLink struct {
-	// References the metric id
-	ID       string `json:"id"`
-	Label    string `json:"label"`
-	URL      string `json:"url"`
-	Priority int    `json:"priority"`
-}
-
-// Variable name for the query within the metrics graph url
+// Replacement variable name for the query in the metrics graph url
 const urlQueryVarName = ":query"

 var (
-	// Available metric links
-	linkTemplates = []MetricLink{
-		{ID: docker.CPUTotalUsage, Label: "CPU", Priority: 1},
-		{ID: docker.MemoryUsage, Label: "Memory", Priority: 2},
+	// Metadata for shown queries
+	shownQueries = []struct {
+		ID    string
+		Label string
+	}{
+		{
+			ID:    docker.CPUTotalUsage,
+			Label: "CPU",
+		},
+		{
+			ID:    docker.MemoryUsage,
+			Label: "Memory",
+		},
+		{
+			ID:    "receive_bytes",
+			Label: "Rx/s",
+		},
+		{
+			ID:    "transmit_bytes",
+			Label: "Tx/s",
+		},
 	}

 	// Prometheus queries for topologies
+	//
+	// Metrics
+	// - `container_cpu_usage_seconds_total` --> cAdvisor in Kubelets.
+	// - `container_memory_usage_bytes` --> cAdvisor in Kubelets.
 	topologyQueries = map[string]map[string]*template.Template{
-		report.Pod: {
-			// `container_memory_usage_bytes` is provided by cAdvisor in Kubelets.
-			docker.MemoryUsage: parsedTemplate(`sum(container_memory_usage_bytes{pod_name="{{.Label}}"})`),
-			// `container_cpu_usage_seconds_total` is provided by cAdvisor in Kubelets.
+		// Containers
+
+		report.Container: {
+			docker.MemoryUsage:   parsedTemplate(`sum(container_memory_usage_bytes{container_name="{{.Label}}"})`),
+			docker.CPUTotalUsage: parsedTemplate(`sum(rate(container_cpu_usage_seconds_total{container_name="{{.Label}}"}[1m]))`),
+		},
+		report.ContainerImage: {
+			docker.MemoryUsage:   parsedTemplate(`sum(container_memory_usage_bytes{image="{{.Label}}"})`),
+			docker.CPUTotalUsage: parsedTemplate(`sum(rate(container_cpu_usage_seconds_total{image="{{.Label}}"}[1m]))`),
+		},
+		"group:container:docker_container_hostname": {
+			docker.MemoryUsage:   parsedTemplate(`sum(container_memory_usage_bytes{pod_name="{{.Label}}"})`),
 			docker.CPUTotalUsage: parsedTemplate(`sum(rate(container_cpu_usage_seconds_total{pod_name="{{.Label}}"}[1m]))`),
 		},
-		report.Deployment: {
-			// `container_memory_usage_bytes` is provided by cAdvisor in Kubelets.
-			// Pod names are automatically generated by k8s using the deployment name:
-			// https://kubernetes.io/docs/concepts/workloads/controllers/deployment/#pod-template-hash-label
-			docker.MemoryUsage: parsedTemplate(`sum(container_memory_usage_bytes{pod_name=~"^{{.Label}}-[^-]+-[^-]+$"})`),
-			// `container_cpu_usage_seconds_total` is provided by cAdvisor in Kubelets.
+
+		// Kubernetes topologies
+
+		report.Pod: {
+			docker.MemoryUsage:   parsedTemplate(`sum(container_memory_usage_bytes{pod_name="{{.Label}}"})`),
+			docker.CPUTotalUsage: parsedTemplate(`sum(rate(container_cpu_usage_seconds_total{pod_name="{{.Label}}"}[1m]))`),
+			"receive_bytes":      parsedTemplate(`sum(rate(container_network_receive_bytes_total{pod_name="{{.Label}}"}[5m]))`),
+			"transmit_bytes":     parsedTemplate(`sum(rate(container_network_transmit_bytes_total{pod_name="{{.Label}}"}[5m]))`),
+		},
+		// Pod naming:
+		// https://kubernetes.io/docs/concepts/workloads/controllers/deployment/#pod-template-hash-label
+		"__k8s_controllers": {
+			docker.MemoryUsage:   parsedTemplate(`sum(container_memory_usage_bytes{pod_name=~"^{{.Label}}-[^-]+-[^-]+$"})`),
 			docker.CPUTotalUsage: parsedTemplate(`sum(rate(container_cpu_usage_seconds_total{pod_name=~"^{{.Label}}-[^-]+-[^-]+$"}[1m]))`),
 		},
 		report.DaemonSet: {
-			// `container_memory_usage_bytes` is provided by cAdvisor in Kubelets.
-			// Pod names are automatically generated by k8s using the DaemonSet name.
-			docker.MemoryUsage: parsedTemplate(`sum(container_memory_usage_bytes{pod_name=~"^{{.Label}}-[^-]+$"})`),
-			// `container_cpu_usage_seconds_total` is provided by cAdvisor in Kubelets.
+			docker.MemoryUsage:   parsedTemplate(`sum(container_memory_usage_bytes{pod_name=~"^{{.Label}}-[^-]+$"})`),
 			docker.CPUTotalUsage: parsedTemplate(`sum(rate(container_cpu_usage_seconds_total{pod_name=~"^{{.Label}}-[^-]+$"}[1m]))`),
 		},
 		report.Service: {
@@ -59,45 +83,40 @@ var (
 			// NB: Pods need to be labeled and selected by their respective Service name, meaning:
 			// - The Service's `spec.selector` needs to select on `name`
 			// - The Service's `metadata.name` needs to be the same value as `spec.selector.name`
-			docker.MemoryUsage: parsedTemplate(`namespace_label_name:container_memory_usage_bytes:sum{label_name="{{.Label}}"}`),
+			docker.MemoryUsage:   parsedTemplate(`namespace_label_name:container_memory_usage_bytes:sum{label_name="{{.Label}}"}`),
 			docker.CPUTotalUsage: parsedTemplate(`namespace_label_name:container_cpu_usage_seconds_total:sum_rate{label_name="{{.Label}}}`),
 		},
 	}
+	k8sControllers = map[string]struct{}{
+		report.Deployment: {},
+		"stateful_set":    {},
+		"cron_job":        {},
+	}
 )

-// 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 {
-	queries := topologyQueries[n.Topology]
-	if len(queries) == 0 {
-		return nil
-	}
-
-	links := []MetricLink{}
-	for _, link := range linkTemplates {
-		if _, ok := queries[link.ID]; ok {
-			links = append(links, link)
-		}
-	}
-
-	return links
-}
-
-// 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, metricsGraphURL string) NodeSummary {
-	queries := topologyQueries[n.Topology]
-	if len(queries) == 0 || len(summary.MetricLinks) == 0 {
+// RenderMetricURLs sets respective URLs for metrics in a node summary. Missing metrics
+// where we have a query for will be appended as an empty metric (no values or samples).
+func RenderMetricURLs(summary NodeSummary, n report.Node, metricsGraphURL string) NodeSummary {
+	if metricsGraphURL == "" {
 		return summary
 	}

-	links := []MetricLink{}
+	queries := getTopologyQueries(n.Topology)
+	if len(queries) == 0 {
+		return summary
+	}
+
+	var maxprio float64
 	var bs bytes.Buffer
-	for _, link := range summary.MetricLinks {
-		tpl := queries[link.ID]
+	var ms []report.MetricRow
+	found := make(map[string]struct{})
+
+	// Set URL on existing metrics
+	for _, metric := range summary.Metrics {
+		if metric.Priority > maxprio {
+			maxprio = metric.Priority
+		}
+		tpl := queries[metric.ID]
 		if tpl == nil {
 			continue
 		}
@@ -107,19 +126,47 @@ func RenderMetricLinks(summary NodeSummary, n report.Node, metricsGraphURL strin
 			continue
 		}

-		link.URL = buildURL(bs.String(), metricsGraphURL)
-		links = append(links, link)
+		ms = append(ms, metric)
+		ms[len(ms)-1].URL = buildURL(bs.String(), metricsGraphURL)
+		found[metric.ID] = struct{}{}
 	}
-	summary.MetricLinks = links
+
+	// Append empty metrics for unattached queries
+	for _, metadata := range shownQueries {
+		if _, ok := found[metadata.ID]; ok {
+			continue
+		}
+
+		tpl := queries[metadata.ID]
+		if tpl == nil {
+			continue
+		}
+
+		bs.Reset()
+		if err := tpl.Execute(&bs, summary); err != nil {
+			continue
+		}
+
+		maxprio++
+		ms = append(ms, report.MetricRow{
+			ID:         metadata.ID,
+			Label:      metadata.Label,
+			URL:        buildURL(bs.String(), metricsGraphURL),
+			Metric:     &report.Metric{},
+			Priority:   maxprio,
+			ValueEmpty: true,
+		})
+	}
+
+	summary.Metrics = ms

 	return summary
 }

-// buildURL puts together the URL by looking at the configured
-// `metricsGraphURL`.
+// buildURL puts together the URL by looking at the configured `metricsGraphURL`.
 func buildURL(query, metricsGraphURL string) string {
 	if strings.Contains(metricsGraphURL, urlQueryVarName) {
-		return strings.Replace(metricsGraphURL, urlQueryVarName, url.PathEscape(query), -1)
+		return strings.Replace(metricsGraphURL, urlQueryVarName, url.QueryEscape(query), -1)
 	}

 	params, err := queryParamsAsJSON(query)
@@ -131,7 +178,7 @@ func buildURL(query, metricsGraphURL string) string {
 		metricsGraphURL += "/"
 	}

-	return metricsGraphURL + url.PathEscape(params)
+	return metricsGraphURL + url.QueryEscape(params)
 }

 // queryParamsAsJSON packs the query into a JSON of the
@@ -163,3 +210,10 @@ func parsedTemplate(query string) *template.Template {

 	return tpl
 }
+
+func getTopologyQueries(t string) map[string]*template.Template {
+	if _, ok := k8sControllers[t]; ok {
+		t = "__k8s_controllers"
+	}
+	return topologyQueries[t]
+}
--- a/render/detailed/links_test.go
+++ b/render/detailed/links_test.go
@@ -10,54 +10,82 @@ import (
 	"github.com/stretchr/testify/assert"
 )

-var (
-	sampleReport      = report.Report{}
-	samplePodNode     = report.MakeNode("noo").WithTopology(report.Pod)
-	sampleUnknownNode = report.MakeNode("???").WithTopology("foo")
+const (
+	sampleMetricsGraphURL = "/prom/:orgID/notebook/new"
 )

-func TestNodeMetricLinks_UnknownTopology(t *testing.T) {
-	links := detailed.NodeMetricLinks(sampleReport, sampleUnknownNode)
-	assert.Nil(t, links)
-}
-
-func TestNodeMetricLinks(t *testing.T) {
-	expected := []detailed.MetricLink{
-		{ID: docker.CPUTotalUsage, Label: "CPU", Priority: 1, URL: ""},
-		{ID: docker.MemoryUsage, Label: "Memory", Priority: 2, URL: ""},
+var (
+	sampleUnknownNode = report.MakeNode("???").WithTopology("foo")
+	samplePodNode     = report.MakeNode("noo").WithTopology(report.Pod)
+	sampleMetrics     = []report.MetricRow{
+		{ID: docker.MemoryUsage},
+		{ID: docker.CPUTotalUsage},
 	}
+)

-	links := detailed.NodeMetricLinks(sampleReport, samplePodNode)
-	assert.Equal(t, expected, links)
+func TestRenderMetricURLs_Disabled(t *testing.T) {
+	s := detailed.NodeSummary{Label: "foo", Metrics: sampleMetrics}
+	result := detailed.RenderMetricURLs(s, samplePodNode, "")
+
+	assert.Empty(t, result.Metrics[0].URL)
+	assert.Empty(t, result.Metrics[1].URL)
 }

-func TestRenderMetricLinks_UnknownTopology(t *testing.T) {
-	summary := detailed.NodeSummary{}
+func TestRenderMetricURLs_UnknownTopology(t *testing.T) {
+	s := detailed.NodeSummary{Label: "foo", Metrics: sampleMetrics}
+	result := detailed.RenderMetricURLs(s, sampleUnknownNode, sampleMetricsGraphURL)

-	result := detailed.RenderMetricLinks(summary, sampleUnknownNode, "")
-	assert.Equal(t, summary, result)
+	assert.Empty(t, result.Metrics[0].URL)
+	assert.Empty(t, result.Metrics[1].URL)
 }

-func TestRenderMetricLinks_Pod(t *testing.T) {
-	summary := detailed.NodeSummary{Label: "woo", MetricLinks: detailed.NodeMetricLinks(sampleReport, samplePodNode)}
+func TestRenderMetricURLs(t *testing.T) {
+	s := detailed.NodeSummary{Label: "foo", Metrics: sampleMetrics}
+	result := detailed.RenderMetricURLs(s, samplePodNode, sampleMetricsGraphURL)

-	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)
-	assert.Equal(t,
-		"/prom/:orgID/notebook/new/%7B%22cells%22:%5B%7B%22queries%22:%5B%22sum%28container_memory_usage_bytes%7Bpod_name=%5C%22woo%5C%22%7D%29%22%5D%7D%5D%7D",
-		result.MetricLinks[1].URL)
+	u := "/prom/:orgID/notebook/new/%7B%22cells%22%3A%5B%7B%22queries%22%3A%5B%22sum%28container_memory_usage_bytes%7Bpod_name%3D%5C%22foo%5C%22%7D%29%22%5D%7D%5D%7D"
+	assert.Equal(t, u, result.Metrics[0].URL)
+	u = "/prom/:orgID/notebook/new/%7B%22cells%22%3A%5B%7B%22queries%22%3A%5B%22sum%28rate%28container_cpu_usage_seconds_total%7Bpod_name%3D%5C%22foo%5C%22%7D%5B1m%5D%29%29%22%5D%7D%5D%7D"
+	assert.Equal(t, u, result.Metrics[1].URL)
 }

-func TestRenderMetricLinks_QueryReplacement(t *testing.T) {
-	summary := detailed.NodeSummary{Label: "boo", MetricLinks: detailed.NodeMetricLinks(sampleReport, samplePodNode)}
+func TestRenderMetricURLs_EmptyMetrics(t *testing.T) {
+	result := detailed.RenderMetricURLs(detailed.NodeSummary{}, samplePodNode, sampleMetricsGraphURL)

-	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)
-	assert.Equal(t,
-		"/foo/:orgID/bar?q=sum%28container_memory_usage_bytes%7Bpod_name=%22boo%22%7D%29",
-		result.MetricLinks[1].URL)
+	m := result.Metrics[0]
+	assert.Equal(t, docker.CPUTotalUsage, m.ID)
+	assert.Equal(t, "CPU", m.Label)
+	assert.NotEmpty(t, m.URL)
+	assert.True(t, m.ValueEmpty)
+	assert.Equal(t, float64(1), m.Priority)
+
+	m = result.Metrics[1]
+	assert.NotEmpty(t, m.URL)
+	assert.True(t, m.ValueEmpty)
+	assert.Equal(t, float64(2), m.Priority)
+}
+
+func TestRenderMetricURLs_CombinedEmptyMetrics(t *testing.T) {
+	s := detailed.NodeSummary{
+		Label:   "foo",
+		Metrics: []report.MetricRow{{ID: docker.MemoryUsage, Priority: 1}},
+	}
+	result := detailed.RenderMetricURLs(s, samplePodNode, sampleMetricsGraphURL)
+
+	assert.NotEmpty(t, result.Metrics[0].URL)
+	assert.False(t, result.Metrics[0].ValueEmpty)
+
+	assert.NotEmpty(t, result.Metrics[1].URL)
+	assert.True(t, result.Metrics[1].ValueEmpty)
+	assert.Equal(t, float64(2), result.Metrics[1].Priority) // first empty metric starts at non-empty prio + 1
+}
+
+func TestRenderMetricURLs_QueryReplacement(t *testing.T) {
+	s := detailed.NodeSummary{Label: "foo", Metrics: sampleMetrics}
+	result := detailed.RenderMetricURLs(s, samplePodNode, "http://example.test/?q=:query")
+
+	u := "http://example.test/?q=sum%28container_memory_usage_bytes%7Bpod_name%3D%22foo%22%7D%29"
+	assert.Equal(t, u, result.Metrics[0].URL)
+	u = "http://example.test/?q=sum%28rate%28container_cpu_usage_seconds_total%7Bpod_name%3D%22foo%22%7D%5B1m%5D%29%29"
+	assert.Equal(t, u, result.Metrics[1].URL)
 }
--- a/render/detailed/summary.go
+++ b/render/detailed/summary.go
@@ -44,20 +44,19 @@ type Column struct {

 // NodeSummary is summary information about a child for a Node.
 type NodeSummary struct {
-	ID          string               `json:"id"`
-	Label       string               `json:"label"`
-	LabelMinor  string               `json:"labelMinor"`
-	Rank        string               `json:"rank"`
-	Shape       string               `json:"shape,omitempty"`
-	Stack       bool                 `json:"stack,omitempty"`
-	Linkable    bool                 `json:"linkable,omitempty"` // Whether this node can be linked-to
-	Pseudo      bool                 `json:"pseudo,omitempty"`
-	Metadata    []report.MetadataRow `json:"metadata,omitempty"`
-	Parents     []Parent             `json:"parents,omitempty"`
-	Metrics     []report.MetricRow   `json:"metrics,omitempty"`
-	Tables      []report.Table       `json:"tables,omitempty"`
-	Adjacency   report.IDList        `json:"adjacency,omitempty"`
-	MetricLinks []MetricLink         `json:"metric_links,omitempty"`
+	ID         string               `json:"id"`
+	Label      string               `json:"label"`
+	LabelMinor string               `json:"labelMinor"`
+	Rank       string               `json:"rank"`
+	Shape      string               `json:"shape,omitempty"`
+	Stack      bool                 `json:"stack,omitempty"`
+	Linkable   bool                 `json:"linkable,omitempty"` // Whether this node can be linked-to
+	Pseudo     bool                 `json:"pseudo,omitempty"`
+	Metadata   []report.MetadataRow `json:"metadata,omitempty"`
+	Parents    []Parent             `json:"parents,omitempty"`
+	Metrics    []report.MetricRow   `json:"metrics,omitempty"`
+	Tables     []report.Table       `json:"tables,omitempty"`
+	Adjacency  report.IDList        `json:"adjacency,omitempty"`
 }

 var renderers = map[string]func(NodeSummary, report.Node) (NodeSummary, bool){
@@ -104,20 +103,20 @@ var primaryAPITopology = map[string]string{

 // MakeNodeSummary summarizes a node, if possible.
 func MakeNodeSummary(r report.Report, n report.Node, metricsGraphURL string) (NodeSummary, bool) {
-	metricLinks := metricsGraphURL != ""
 	if renderer, ok := renderers[n.Topology]; ok {
 		// Skip (and don't fall through to fallback) if renderer maps to nil
 		if renderer != nil {
-			summary, b := renderer(baseNodeSummary(r, n, metricLinks), n)
-			return RenderMetricLinks(summary, n, metricsGraphURL), b
+			summary, b := renderer(baseNodeSummary(r, n), n)
+			return RenderMetricURLs(summary, n, metricsGraphURL), b
 		}
 	} else if _, ok := r.Topology(n.Topology); ok {
-		summary := baseNodeSummary(r, n, metricLinks)
+		summary := baseNodeSummary(r, n)
 		summary.Label = n.ID // This is unlikely to look very good, but is a reasonable fallback
 		return summary, true
 	}
 	if strings.HasPrefix(n.Topology, "group:") {
-		return groupNodeSummary(baseNodeSummary(r, n, metricLinks), r, n)
+		summary, b := groupNodeSummary(baseNodeSummary(r, n), r, n)
+		return RenderMetricURLs(summary, n, metricsGraphURL), b
 	}
 	return NodeSummary{}, false
 }
@@ -133,7 +132,7 @@ func (n NodeSummary) SummarizeMetrics() NodeSummary {
 	return n
 }

-func baseNodeSummary(r report.Report, n report.Node, metricLinks bool) NodeSummary {
+func baseNodeSummary(r report.Report, n report.Node) NodeSummary {
 	t, _ := r.Topology(n.Topology)
 	ns := NodeSummary{
 		ID:        n.ID,
@@ -145,9 +144,7 @@ func baseNodeSummary(r report.Report, n report.Node, metricLinks bool) NodeSumma
 		Tables:    NodeTables(r, n),
 		Adjacency: n.Adjacency,
 	}
-	if metricLinks {
-		ns.MetricLinks = NodeMetricLinks(r, n)
-	}
+
 	return ns
 }