[8.16](backport #5854) [helm]: implement support for defining image pull secrets (#5880)

* [helm]: implement support for defining image pull secrets (#5854)

* feat: implement support for defining image pull secrets

* doc: add imagePullSecrets in kubernetes default example

(cherry picked from commit 053b320)

# Conflicts:
#	deploy/helm/elastic-agent/values.yaml

* fix: merge conflicts

---------

Co-authored-by: Panos Koutsovasilis <[email protected]>

Author: mergify[bot]

deploy/helm/elastic-agent/README.md

@@ -133,6 +133,7 @@ The chart built-in [kubernetes integration](https://docs.elastic.co/integrations
 |-----|------|---------|-------------|
 | agent.version | string | `"9.0.0"` | elastic-agent version |
 | agent.image | object | `{"pullPolicy":"IfNotPresent","repository":"docker.elastic.co/beats/elastic-agent","tag":"9.0.0-SNAPSHOT"}` | image configuration |
+| agent.imagePullSecrets | list | `[]` | image pull secrets |
 | agent.engine | string | `"k8s"` | generate kubernetes manifests or [ECK](https://github.com/elastic/cloud-on-k8s) CRDs |
 | agent.unprivileged | bool | `false` | enable unprivileged mode |
 | agent.presets | map[string]{} | `{ "perNode" : {...}, "clusterWide": {...}, "ksmSharded": {...} }` | Map of deployment presets for the Elastic Agent. The key of the map is the name of the preset. See more for the presets required by the built-in Kubernetes integration [here](./values.yaml) |

deploy/helm/elastic-agent/examples/kubernetes-default/README.md

@@ -13,13 +13,30 @@ In this example we install the built-in `kubernetes` integration with the defaul
 2. `kubernetes` integration assets installed through Kibana ([Kibana - Install and uninstall Elastic Agent integration assets](https://www.elastic.co/guide/en/fleet/current/install-uninstall-integration-assets.html))
 
 ## Run:
+
+#### Public image registry:
 ```console
 helm install elastic-agent ../../ \
      -f ./agent-kubernetes-values.yaml \
      --set outputs.default.type=ESSecretAuthAPI \
      --set outputs.default.secretName=es-api-secret
 ```
 
+
+#### Private image registry:
+Create secret with the contents of docker auth config
+```
+kubectl create secret generic regcred --from-file=.dockerconfigjson=<your home folder here>/.docker/config.json --type=kubernetes.io/dockerconfigjson
+```
+
+Install elastic-agent
+```console
+helm install elastic-agent ../../ \
+     -f ./agent-kubernetes-values.yaml \
+     --set 'agent.imagePullSecrets[0].name=regcred' \
+     --set outputs.default.type=ESSecretAuthAPI \
+     --set outputs.default.secretName=es-api-secret
+
 ## Validate:
 
 1. The Kibana `kubernetes`-related dashboards should start showing up the respective info.

deploy/helm/elastic-agent/templates/agent/eck/_pod_template.tpl

@@ -36,6 +36,10 @@
         initContainers:
           {{- . | toYaml | nindent 10 }}
         {{- end }}
+        {{- with $.Values.agent.imagePullSecrets }}
+        imagePullSecrets:
+          {{- . | toYaml | nindent 10 }}
+        {{- end }}
         containers:
           {{- with ($presetVal).extraContainers }}
           {{- . | toYaml | nindent 10 }}

deploy/helm/elastic-agent/templates/agent/k8s/_pod_template.tpl

@@ -63,6 +63,10 @@
       initContainers:
         {{- . | toYaml | nindent 8 }}
       {{- end }}
+      {{- with $.Values.agent.imagePullSecrets }}
+      imagePullSecrets:
+        {{- . | toYaml | nindent 8 }}
+      {{- end }}
       containers:
         {{- with ($presetVal).extraContainers }}
         {{- . | toYaml | nindent 8 }}

deploy/helm/elastic-agent/values.schema.json

@@ -268,6 +268,12 @@
                 "image": {
                     "$ref": "#/definitions/AgentImageConfig"
                 },
+                "imagePullSecrets": {
+                    "type": "array",
+                    "items": {
+                        "type": "object"
+                    }
+                },
                 "engine": {
                     "type": "string",
                     "enum": [

deploy/helm/elastic-agent/values.yaml

@@ -301,6 +301,9 @@ agent:
     repository: docker.elastic.co/beats/elastic-agent
     pullPolicy: IfNotPresent
     tag: "8.16.0-SNAPSHOT"
+  # -- image pull secrets
+  # @section -- 3 - Elastic-Agent Configuration
+  imagePullSecrets: []
   # -- generate kubernetes manifests or [ECK](https://github.com/elastic/cloud-on-k8s) CRDs
   # @section -- 3 - Elastic-Agent Configuration
   engine: k8s # k8s or eck