Fix(exporter): Use namespaced pod listing for iperf server discovery (#23)

- Modified `exporter/exporter.py` to use `list_namespaced_pod()`
  instead of `list_pod_for_all_namespaces()`. This resolves the
  RBAC error where the exporter was incorrectly requesting cluster-scoped
  pod listing permissions.
- The exporter now correctly lists pods only within the namespace
  specified by the `IPERF_SERVER_NAMESPACE` environment variable.

- Reverted Helm chart RBAC templates (`charts/iperf3-monitor/templates/rbac.yaml`)
  and `values.yaml` to their simpler, original state. The previous
  parameterization of `serviceAccount.namespace` is no longer needed,
  as the primary fix is in the exporter code.

The Helm chart should be deployed into the same namespace where the
`iperf3-monitor` ServiceAccount resides and where iperf3 server pods
are located. The `IPERF_SERVER_NAMESPACE` environment variable for the
exporter pod must be set to this namespace.

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

.github/workflows/release.yml

@@ -22,6 +22,15 @@ jobs:
         with:
           version: v3.10.0
 
+      - name: Add Helm repositories
+        run: |
+          helm repo add bjw-s https://bjw-s-labs.github.io/helm-charts/ --force-update
+          helm repo add prometheus-community https://prometheus-community.github.io/helm-charts --force-update
+          helm repo update
+
+      - name: Build Helm chart dependencies
+        run: helm dependency build ./charts/iperf3-monitor
+
       - name: Helm Lint
         run: helm lint ./charts/iperf3-monitor
 
@@ -86,6 +95,15 @@ jobs:
           sudo wget https://github.com/mikefarah/yq/releases/latest/download/yq_linux_amd64 -O /usr/bin/yq &&\
           sudo chmod +x /usr/bin/yq
 
+      - name: Add Helm repositories
+        run: |
+          helm repo add bjw-s https://bjw-s-labs.github.io/helm-charts/ --force-update
+          helm repo add prometheus-community https://prometheus-community.github.io/helm-charts --force-update
+          helm repo update
+
+      - name: Build Helm chart dependencies
+        run: helm dependency build ./charts/iperf3-monitor
+
       - name: Set Chart Version from Tag
         run: |
           VERSION=$(echo "${{ github.ref_name }}" | sed 's/^v//')

charts/iperf3-monitor/grafana/iperf3-dashboard.json

@@ -0,0 +1,194 @@
+{
+"__inputs": [],
+"__requires": [
+{
+"type": "grafana",
+"id": "grafana",
+"name": "Grafana",
+"version": "8.0.0"
+},
+{
+"type": "datasource",
+"id": "prometheus",
+"name": "Prometheus",
+"version": "1.0.0"
+}
+],
+"annotations": {
+"list": [
+{
+"builtIn": 1,
+"datasource": {
+"type": "grafana",
+"uid": "-- Grafana --"
+},
+"enable": true,
+"hide": true,
+"iconColor": "rgba(0, 211, 255, 1)",
+"name": "Annotations & Alerts",
+"type": "dashboard"
+}
+]
+},
+"editable": true,
+"fiscalYearStartMonth": 0,
+"gnetId": null,
+"graphTooltip": 0,
+"id": null,
+"links": [],
+"panels": [
+{
+"datasource": {
+"type": "prometheus",
+"uid": "prometheus"
+},
+"gridPos": {
+"h": 9,
+"w": 24,
+"x": 0,
+"y": 0
+},
+"id": 2,
+"targets": [
+{
+"expr": "avg(iperf_network_bandwidth_mbps) by (source_node, destination_node)",
+"format": "heatmap",
+"legendFormat": "{{source_node}} -> {{destination_node}}",
+"refId": "A"
+}
+],
+"cards": { "cardPadding": null, "cardRound": null },
+"color": {
+"mode": "spectrum",
+"scheme": "red-yellow-green",
+"exponent": 0.5,
+"reverse": false
+},
+"dataFormat": "tsbuckets",
+"yAxis": { "show": true, "format": "short" },
+"xAxis": { "show": true }
+},
+{
+"title": "Bandwidth Over Time (Source: $source_node, Dest: $destination_node)",
+"type": "timeseries",
+"datasource": {
+"type": "prometheus",
+"uid": "prometheus"
+},
+"gridPos": {
+"h": 8,
+"w": 12,
+"x": 0,
+"y": 9
+},
+"targets": [
+{
+"expr": "iperf_network_bandwidth_mbps{source_node=~\"^$source_node$\", destination_node=~\"^$destination_node$\", protocol=~\"^$protocol$\"}",
+"legendFormat": "Bandwidth",
+"refId": "A"
+}
+],
+"fieldConfig": {
+"defaults": {
+"unit": "mbps"
+}
+}
+},
+{
+"title": "Jitter Over Time (Source: $source_node, Dest: $destination_node)",
+"type": "timeseries",
+"datasource": {
+"type": "prometheus",
+"uid": "prometheus"
+},
+"gridPos": {
+"h": 8,
+"w": 12,
+"x": 12,
+"y": 9
+},
+"targets": [
+{
+"expr": "iperf_network_jitter_ms{source_node=~\"^$source_node$\", destination_node=~\"^$destination_node$\", protocol=\"udp\"}",
+"legendFormat": "Jitter",
+"refId": "A"
+}
+],
+"fieldConfig": {
+"defaults": {
+"unit": "ms"
+}
+}
+}
+],
+"refresh": "30s",
+"schemaVersion": 36,
+"style": "dark",
+"tags": ["iperf3", "network", "kubernetes"],
+"templating": {
+"list": [
+{
+"current": {},
+"datasource": {
+"type": "prometheus",
+"uid": "prometheus"
+},
+"definition": "label_values(iperf_network_bandwidth_mbps, source_node)",
+"hide": 0,
+"includeAll": false,
+"multi": false,
+"name": "source_node",
+"options": [],
+"query": "label_values(iperf_network_bandwidth_mbps, source_node)",
+"refresh": 1,
+"regex": "",
+"skipUrlSync": false,
+"sort": 1,
+"type": "query"
+},
+{
+"current": {},
+"datasource": {
+"type": "prometheus",
+"uid": "prometheus"
+},
+"definition": "label_values(iperf_network_bandwidth_mbps{source_node=~\"^$source_node$\"}, destination_node)",
+"hide": 0,
+"includeAll": false,
+"multi": false,
+"name": "destination_node",
+"options": [],
+"query": "label_values(iperf_network_bandwidth_mbps{source_node=~\"^$source_node$\"}, destination_node)",
+"refresh": 1,
+"regex": "",
+"skipUrlSync": false,
+"sort": 1,
+"type": "query"
+},
+{
+"current": { "selected": true, "text": "tcp", "value": "tcp" },
+"hide": 0,
+"includeAll": false,
+"multi": false,
+"name": "protocol",
+"options": [
+{ "selected": true, "text": "tcp", "value": "tcp" },
+{ "selected": false, "text": "udp", "value": "udp" }
+],
+"query": "tcp,udp",
+"skipUrlSync": false,
+"type": "custom"
+}
+]
+},
+"time": {
+"from": "now-1h",
+"to": "now"
+},
+"timepicker": {},
+"timezone": "browser",
+"title": "Kubernetes iperf3 Network Performance",
+"uid": "k8s-iperf3-dashboard",
+"version": 1,
+"weekStart": ""
+}

charts/iperf3-monitor/templates/exporter-controller.yaml

@@ -77,7 +77,7 @@ Proceed with modifications only if the exporter controller is defined.
   {{- if $exporterContainerCfg -}}
     {{- if not $exporterContainerCfg.image.tag -}}
       {{- if $chart.AppVersion -}}
-        {{- $_ := set $exporterContainerCfg.image "tag" $chart.AppVersion -}}
+        {{- $_ := set $exporterContainerCfg.image "tag" (printf "v%s" $chart.AppVersion) -}}
       {{- else -}}
         {{- fail (printf "Error: Container image tag is not specified for controller '%s', container '%s', and Chart.AppVersion is also empty." $exporterControllerKey "exporter") -}}
       {{- end -}}

charts/iperf3-monitor/templates/grafana-dashboard-configmap.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: {{ .Release.Name }}-grafana-dashboard
+  labels:
+    grafana_dashboard: "1"
+    app.kubernetes.io/name: {{ include "iperf3-monitor.name" . }}
+    helm.sh/chart: {{ .Chart.Name }}-{{ .Chart.Version | replace "+" "_" }}
+    app.kubernetes.io/instance: {{ .Release.Name }}
+    app.kubernetes.io/managed-by: {{ .Release.Service }}
+data:
+  iperf3-dashboard.json: |
+    {{ .Files.Get "grafana/iperf3-dashboard.json" | nindent 4 }}

charts/iperf3-monitor/templates/rbac.yaml

@@ -7,9 +7,10 @@ metadata:
     {{- include "iperf3-monitor.labels" . | nindent 4 }}
 ---
 apiVersion: rbac.authorization.k8s.io/v1
-kind: ClusterRole
+kind: Role
 metadata:
   name: {{ include "iperf3-monitor.fullname" . }}-role
+  namespace: {{ .Release.Namespace }}
   labels:
     {{- include "iperf3-monitor.labels" . | nindent 4 }}
 rules:
@@ -18,9 +19,10 @@ rules:
     verbs: ["get", "list", "watch"]
 ---
 apiVersion: rbac.authorization.k8s.io/v1
-kind: ClusterRoleBinding
+kind: RoleBinding
 metadata:
   name: {{ include "iperf3-monitor.fullname" . }}-rb
+  namespace: {{ .Release.Namespace }}
   labels:
     {{- include "iperf3-monitor.labels" . | nindent 4 }}
 subjects:
@@ -28,7 +30,7 @@ subjects:
     name: {{ include "iperf3-monitor.serviceAccountName" . }}
     namespace: {{ .Release.Namespace }}
 roleRef:
-  kind: ClusterRole
+  kind: Role # Changed from ClusterRole
   name: {{ include "iperf3-monitor.fullname" . }}-role
   apiGroup: rbac.authorization.k8s.io
 {{- end -}}

charts/iperf3-monitor/templates/service.yaml

@@ -11,7 +11,7 @@ spec:
     {{- include "iperf3-monitor.selectorLabels" . | nindent 4 }}
     app.kubernetes.io/component: exporter
   ports:
-    - name: metrics
-      port: {{ .Values.service.port }}
-      targetPort: {{ .Values.service.targetPort }}
-      protocol: TCP
+    - name: metrics # Assuming 'metrics' is the intended name, aligns with values structure
+      port: {{ .Values.service.main.ports.metrics.port }}
+      targetPort: {{ .Values.service.main.ports.metrics.targetPort }}
+      protocol: {{ .Values.service.main.ports.metrics.protocol | default "TCP" }}

charts/iperf3-monitor/values.yaml

@@ -86,13 +86,15 @@ controllers:
           #       key: mykey
 
         # -- Ports for the exporter container.
+        # Expected by Kubernetes and bjw-s common library as a list of objects.
         ports:
-          metrics: # Name of the port, will be used in Service definition
+          - name: metrics # Name of the port, referenced by Service's targetPort
             # -- Port number for the metrics endpoint on the container.
-            port: 9876 # Default, should match service.targetPort
+            containerPort: 9876
             # -- Protocol for the metrics port.
-            protocol: TCP # Common library defaults to TCP if not specified.
-            enabled: true # This port is enabled
+            protocol: TCP
+            # -- Whether this port definition is enabled. Specific to bjw-s common library.
+            enabled: true
 
         # -- CPU and memory resource requests and limits for the exporter container.
         resources:

exporter/exporter.py

@@ -92,16 +92,18 @@ def discover_iperf_servers():
 
         logging.info(f"Discovering iperf3 servers with label '{label_selector}' in namespace '{namespace}'")
 
-        ret = v1.list_pod_for_all_namespaces(label_selector=label_selector, watch=False)
+        # Use list_namespaced_pod to query only the specified namespace
+        ret = v1.list_namespaced_pod(namespace=namespace, label_selector=label_selector, watch=False)
 
         servers = []
         for item in ret.items:
+            # No need to filter by namespace here as the API call is already namespaced
             if item.status.pod_ip and item.status.phase == 'Running':
                 servers.append({
                     'ip': item.status.pod_ip,
                     'node_name': item.spec.node_name # Node where the iperf server pod is running
                 })
-        logging.info(f"Discovered {len(servers)} iperf3 server pods.")
+        logging.info(f"Discovered {len(servers)} iperf3 server pods in namespace '{namespace}'.")
         return servers
     except config.ConfigException as e:
         logging.error(f"Kubernetes config error: {e}. Is the exporter running in a cluster with RBAC permissions?")