Documentation: callout templating escapes for helm users (#2704)

* callout templating escapes for helm users

Signed-off-by: rteeling <rteeling@users.noreply.github.com>

* quote the snippet file

Signed-off-by: rteeling <rteeling@users.noreply.github.com>

---------

Signed-off-by: rteeling <rteeling@users.noreply.github.com>
Co-authored-by: rteeling <rteeling@users.noreply.github.com>

docs/guides/templating.md

@@ -2,6 +2,15 @@
 
 With External Secrets Operator you can transform the data from the external secret provider before it is stored as `Kind=Secret`. You can do this with the `Spec.Target.Template`. Each data value is interpreted as a [golang template](https://golang.org/pkg/text/template/).
 
+
+## Helm
+
+When installing ExternalSecrets via `helm`, the template must be escaped so that `helm` will not try to render it. The most straightforward way to accomplish this would be to use backticks ([raw string constants](https://pkg.go.dev/text/template#hdr-Examples)):
+
+```yaml
+{% include 'helm-template-v2-escape-sequence.yaml' %}
+```
+
 ## Examples
 
 You can use templates to inject your secrets into a configuration file that you mount into your pod:

docs/snippets/helm-template-v2-escape-sequence.yaml

@@ -0,0 +1,19 @@
+{% raw %}
+apiVersion: external-secrets.io/v1beta1
+kind: ExternalSecret
+metadata:
+  name: template
+spec:
+  # ...
+  target:
+    template:
+      engineVersion: v2
+      data:
+        name: admin
+        # password: "{{ .mysecret }}"               # If you are using plain manifests or gitops tools
+        password: "{{ `{{ .mysecret }}` }}"         # If you are using helm
+  data:
+  - secretKey: mysecret
+    remoteRef:
+      key: /credentials
+{% endraw %}

docs/snippets/multikey-template-v2-external-secret.yaml

@@ -11,7 +11,7 @@ spec:
       data:
         name: admin
         password: "{{ .mysecret }}"                   # If you are using plain manifests or gitops tools
-        # password: '{{ printf "{{ .mysecret }}" }}'  # If you are using templated tools like helm
+        # password: "{{ `{{ .mysecret }}` }}"         # If you are using templated tools like helm
   data:
   - secretKey: mysecret
     remoteRef: