Support for tpl function in extra env values (#21)

* Support for tpl function in extra env values

* Added ci tpl function test values

* bump chart version up

* updates to tpl test values and readme

Author: abhilashjoseph

helm/oauth2-proxy/Chart.yaml

@@ -1,5 +1,5 @@
 name: oauth2-proxy
-version: 3.3.1
+version: 3.3.2
 apiVersion: v2
 appVersion: 7.1.3
 home: https://oauth2-proxy.github.io/oauth2-proxy/

helm/oauth2-proxy/README.md

@@ -178,3 +178,17 @@ data:
   cert.pem: AB..==
   cert.key: CD..==
 ```
+## Extra environment variable templating
+The extraEnv value supports the tpl function which evaluate strings as templates inside the deployment template.
+This is useful to pass a template string as a value to the chart's extra environment variables and to render external configuration environment values
+
+
+```yaml
+...
+tplValue: "This is a test value for the tpl function"
+extraEnv:
+  - name: TEST_ENV_VAR_1
+    value: test_value_1
+  - name: TEST_ENV_VAR_2
+    value: '{{ .Values.tplValue }}'
+```

helm/oauth2-proxy/ci/extra-env-tpl-values.yaml

@@ -0,0 +1,6 @@
+tplValue: "This is a test value for the template function"
+extraEnv:
+  - name: TEST_ENV_VAR_1
+    value: test_value_1
+  - name: TEST_ENV_VAR_2
+    value: '{{ .Values.tplValue }}'

helm/oauth2-proxy/templates/deployment.yaml

@@ -130,7 +130,7 @@ spec:
         {{- end }}
         {{- end }}
         {{- if .Values.extraEnv }}
-{{ toYaml .Values.extraEnv | indent 8 }}
+{{ tpl (toYaml .Values.extraEnv) . | indent 8 }}
         {{- end }}
         ports:
           - containerPort: 4180