Adding a config.toml value to the helm chart

Fixes https://github.com/gomods/athens/issues/1405

cc/ @hypnoglow

charts/athens-proxy/templates/config-configtoml.yaml

@@ -0,0 +1,14 @@
+{{- if .Values.configToml.enabled -}}
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: {{ template "fullname" . }}-configtoml
+  labels:
+    app: {{ template "fullname" . }}
+    chart: "{{ .Chart.Name }}-{{ .Chart.Version }}"
+    release: "{{ .Release.Name }}"
+    heritage: "{{ .Release.Service }}"
+data:
+  config.toml: |-
+    {{ .Values.configToml.data }}
+{{- end -}}

charts/athens-proxy/templates/deployment.yaml

@@ -155,6 +155,11 @@ spec:
           mountPath: "/usr/local/lib"
           readOnly: true
         {{- end }}
+        {{- if .Values.configToml}}
+        - name: configtoml
+          mountPath: "/config"
+          readOnly: true
+        {{- end }}
         {{- if .Values.netrc.enabled }}
         - name: netrc
           mountPath: "/etc/netrc"
@@ -192,6 +197,11 @@ spec:
         configMap:
           name: {{ template "fullname" . }}-upstream
       {{- end }}
+      {{- if .Values.configToml.enabled }}
+      - name: configtoml-config
+        configMap:
+          name: {{ template "fullname" .}}-configtoml
+      {{- end }}
       {{- if .Values.netrc.enabled }}
       - name: netrc
         secret:

charts/athens-proxy/values.yaml

@@ -82,6 +82,16 @@ gitconfig:
   # Key in the kubernetes secret that contains git config data.
   secretKey: gitconfig
 
+configToml:
+  enabled: false
+  data: |-
+    # See https://docs.gomods.io/configuration/ for an introduction on what
+    # values you can put in here.
+    # 
+    # Otherwise, for an exhaustive list of the configuration values you 
+    # can put here, see config.dev.toml at the root of the 
+    # github.com/gomods/athens repository 
+    
 upstreamProxy:
   # This is where you can set the URL for the upstream module repository.
   # If 'enabled' is set to true, Athens will try to download modules from the upstream when it doesn't find them in its own storage.