codegen: allow setting conditional environment variables (#512)

changelog/v0.34.9/conditional-env.yaml

@@ -0,0 +1,7 @@
+changelog:
+  - type: NEW_FEATURE
+    issueLink: https://github.com/solo-io/gloo-mesh-enterprise/issues/12370
+    resolvesIssue: false
+    description: |
+      Add support for conditional template environment variables.
+    skipCI: false

codegen/cmd_test.go

@@ -1836,7 +1836,7 @@ roleRef:
 			[]v1.EnvVar{{Name: "FOO", ValueFrom: &v1.EnvVarSource{SecretKeyRef: &v1.SecretKeySelector{LocalObjectReference: v1.LocalObjectReference{Name: "bar"}, Key: "baz"}}}}),
 	)
 
-	Describe("rendering feature gate env vars", func() {
+	Describe("rendering template env vars", func() {
 		var tmpDir string
 
 		BeforeEach(func() {
@@ -1968,6 +1968,43 @@ roleRef:
 					{Name: "FOO", Value: "bar"},
 					{Name: "FEATURE_ENABLE_FOO", Value: "false"},
 				}),
+			Entry("when Env and Conditional TemplateEnvVar are specified, and condition is true",
+				map[string]string{"Foo": "false"},
+				[]v1.EnvVar{
+					{
+						Name:  "FOO",
+						Value: "bar",
+					},
+				},
+				[]TemplateEnvVar{
+					{
+						Condition: "$.Values.featureGates.Foo",
+						Name:      "FEATURE_ENABLE_FOO",
+						Value:     "{{ $.Values.featureGates.Foo | quote }}",
+					},
+				},
+				[]v1.EnvVar{
+					{Name: "FOO", Value: "bar"},
+					{Name: "FEATURE_ENABLE_FOO", Value: "false"},
+				}),
+			Entry("when Env and Conditional TemplateEnvVar are specified, and condition is false",
+				map[string]string{"Foo": "false"},
+				[]v1.EnvVar{
+					{
+						Name:  "FOO",
+						Value: "bar",
+					},
+				},
+				[]TemplateEnvVar{
+					{
+						Condition: "$.Values.featureGates.InvalidCondition",
+						Name:      "FEATURE_ENABLE_FOO",
+						Value:     "{{ $.Values.featureGates.Foo | quote }}",
+					},
+				},
+				[]v1.EnvVar{
+					{Name: "FOO", Value: "bar"},
+				}),
 		)
 	})
 

codegen/model/chart.go

@@ -153,6 +153,10 @@ type ConditionalVolumeMount struct {
 
 // TemplateEnvVar corresponds to an environment variable that can use templated Helm values
 type TemplateEnvVar struct {
+	// Condition for this environment variable to be rendered
+	// E.g. `and (.Values.operator.customValueA) (.Values.operator.customValueB)`
+	Condition string
+
 	// Name of the environment variable
 	// E.g. FOO_BAR
 	Name string

codegen/templates/chart/operator-deployment.yamltmpl

@@ -120,8 +120,14 @@ spec:
         env:
 {{ toYaml [[ $containerVar ]].env | indent 10 }}
 [[- range $f := $container.TemplateEnvVars ]]
+[[- if $f.Condition ]]
+{{- if [[ $f.Condition ]] }}
+[[- end]]
           - name: [[ $f.Name ]]
             value: [[ $f.Value ]]
+[[- if $f.Condition ]]
+{{- end }}
+[[- end]]
 [[- end ]]
 {{- else if [[ $containerVar ]].extraEnvs }}
         env: