First sidecar module: OpenTelemetry (#8013)

* remove opentelemetry from main nginx image

* add opentelemetry sidecar image

* handle extra modules in helm chart

* fix running helm chart

* mount the modules volume in the init container

* merge the mounted folder

* fix the otel image

* fix licence year

* fix cloudbuild image

* use the same nginx version as in the main image

* only retrieve /etc/nginx/modules for now

charts/ingress-nginx/ci/daemonset-extra-modules.yaml

@@ -0,0 +1,10 @@
+controller:
+  kind: DaemonSet
+  image:
+    repository: ingress-controller/controller
+    tag: 1.0.0-dev
+  service:
+    type: ClusterIP
+  extraModules:
+    - name: opentelemetry
+      image: busybox

charts/ingress-nginx/ci/deployment-extra-modules.yaml

@@ -0,0 +1,10 @@
+controller:
+  image:
+    repository: ingress-controller/controller
+    tag: 1.0.0-dev
+    digest: null
+  service:
+    type: ClusterIP
+  extraModules:
+    - name: opentelemetry
+      image: busybox

charts/ingress-nginx/templates/controller-daemonset.yaml

@@ -143,8 +143,12 @@ spec:
               hostPort: {{ $key }}
               {{- end }}
           {{- end }}
-        {{- if (or .Values.controller.customTemplate.configMapName .Values.controller.extraVolumeMounts .Values.controller.admissionWebhooks.enabled) }}
+        {{- if (or .Values.controller.customTemplate.configMapName .Values.controller.extraVolumeMounts .Values.controller.admissionWebhooks.enabled .Values.controller.extraModules) }}
           volumeMounts:
+          {{- if .Values.controller.extraModules }}
+            - name: modules
+              mountPath: /modules_mount
+          {{- end }}
           {{- if .Values.controller.customTemplate.configMapName }}
             - mountPath: /etc/nginx/template
               name: nginx-template-volume
@@ -165,8 +169,20 @@ spec:
       {{- if .Values.controller.extraContainers }}
         {{ toYaml .Values.controller.extraContainers | nindent 8 }}
       {{- end }}
-    {{- if .Values.controller.extraInitContainers }}
-      initContainers: {{ toYaml .Values.controller.extraInitContainers | nindent 8 }}
+
+
+    {{- if (or .Values.controller.extraInitContainers .Values.controller.extraModules) }}
+      initContainers:
+      {{- if .Values.controller.extraInitContainers }}
+        {{ toYaml .Values.controller.extraInitContainers | nindent 8 }}
+      {{- end }}
+      {{- if .Values.controller.extraModules }}
+        {{- range .Values.controller.extraModules }}
+          - name: {{ .Name }}
+            image: {{ .Image }}
+            command: ['sh', '-c', '/usr/local/bin/init_module.sh']
+        {{- end }}
+      {{- end }}
     {{- end }}
     {{- if .Values.controller.hostNetwork }}
       hostNetwork: {{ .Values.controller.hostNetwork }}
@@ -185,8 +201,12 @@ spec:
     {{- end }}
       serviceAccountName: {{ template "ingress-nginx.serviceAccountName" . }}
       terminationGracePeriodSeconds: {{ .Values.controller.terminationGracePeriodSeconds }}
-    {{- if (or .Values.controller.customTemplate.configMapName .Values.controller.extraVolumeMounts .Values.controller.admissionWebhooks.enabled .Values.controller.extraVolumes) }}
+    {{- if (or .Values.controller.customTemplate.configMapName .Values.controller.extraVolumeMounts .Values.controller.admissionWebhooks.enabled .Values.controller.extraVolumes .Values.controller.extraModules) }}
       volumes:
+      {{- if .Values.controller.extraModules }}
+        - name: modules
+          emptyDir: {}
+      {{- end }}
       {{- if .Values.controller.customTemplate.configMapName }}
         - name: nginx-template-volume
           configMap:

charts/ingress-nginx/templates/controller-deployment.yaml

@@ -140,8 +140,12 @@ spec:
               hostPort: {{ $key }}
               {{- end }}
           {{- end }}
-        {{- if (or .Values.controller.customTemplate.configMapName .Values.controller.extraVolumeMounts .Values.controller.admissionWebhooks.enabled) }}
+        {{- if (or .Values.controller.customTemplate.configMapName .Values.controller.extraVolumeMounts .Values.controller.admissionWebhooks.enabled .Values.controller.extraModules) }}
           volumeMounts:
+          {{- if .Values.controller.extraModules }}
+            - name: modules
+              mountPath: /modules_mount
+          {{- end }}
           {{- if .Values.controller.customTemplate.configMapName }}
             - mountPath: /etc/nginx/template
               name: nginx-template-volume
@@ -162,8 +166,21 @@ spec:
       {{- if .Values.controller.extraContainers }}
         {{ toYaml .Values.controller.extraContainers | nindent 8 }}
       {{- end }}
-    {{- if .Values.controller.extraInitContainers }}
-      initContainers: {{ toYaml .Values.controller.extraInitContainers | nindent 8 }}
+    {{- if (or .Values.controller.extraInitContainers .Values.controller.extraModules) }}
+      initContainers:
+      {{- if .Values.controller.extraInitContainers }}
+        {{ toYaml .Values.controller.extraInitContainers | nindent 8 }}
+      {{- end }}
+      {{- if .Values.controller.extraModules }}
+        {{- range .Values.controller.extraModules }}
+          - name: {{ .name }}
+            image: {{ .image }}
+            command: ['sh', '-c', '/usr/local/bin/init_module.sh']
+            volumeMounts:
+              - name: modules
+                mountPath: /modules_mount
+        {{- end }}
+      {{- end }}
     {{- end }}
     {{- if .Values.controller.hostNetwork }}
       hostNetwork: {{ .Values.controller.hostNetwork }}
@@ -182,8 +199,12 @@ spec:
     {{- end }}
       serviceAccountName: {{ template "ingress-nginx.serviceAccountName" . }}
       terminationGracePeriodSeconds: {{ .Values.controller.terminationGracePeriodSeconds }}
-    {{- if (or .Values.controller.customTemplate.configMapName .Values.controller.extraVolumeMounts .Values.controller.admissionWebhooks.enabled .Values.controller.extraVolumes) }}
+    {{- if (or .Values.controller.customTemplate.configMapName .Values.controller.extraVolumeMounts .Values.controller.admissionWebhooks.enabled .Values.controller.extraVolumes .Values.controller.extraModules) }}
       volumes:
+      {{- if .Values.controller.extraModules }}
+        - name: modules
+          emptyDir: {}
+      {{- end }}
       {{- if .Values.controller.customTemplate.configMapName }}
         - name: nginx-template-volume
           configMap:

charts/ingress-nginx/values.yaml

@@ -559,6 +559,15 @@ controller:
   #   image: busybox
   #   command: ['sh', '-c', 'until nslookup myservice; do echo waiting for myservice; sleep 2; done;']
 
+  extraModules: []
+  ## Modules, which are mounted into the core nginx image
+  # - name: opentelemetry
+  #   image: busybox
+  #
+  # The image must contain a `/usr/local/bin/init_module.sh` executable, which
+  # will be executed as initContainers, to move its config files within the
+  # mounted volume.
+
   admissionWebhooks:
     annotations: {}
     # ignore-check.kube-linter.io/no-read-only-rootfs: "This deployment needs write access to root filesystem".