Add list of supported values for flags that represent an enum field

.codegen/service.go.tmpl

@@ -26,6 +26,13 @@ import (
 	{{skipThisFile}}
 {{end}}
 
+{{define "printArray" -}}
+{{if le (len .) 5 -}}
+	[{{range $index, $element := .}}{{if ne $index 0}}, {{end}}{{$element.Name}}{{end}}]
+{{- else -}}[{{range $index, $element := .}}
+  {{$element.Name}},{{end}}
+]{{end}}{{end}}
+
 {{define "service"}}
 // Slice with functions to override default command behavior.
 // Functions can be added from the `init()` function in manually curated files in this directory.
@@ -106,7 +113,7 @@ func new{{.PascalName}}() *cobra.Command {
 			{{else if .Entity.ArrayValue }}// TODO: array: {{.Name}}
 			{{else if .Entity.MapValue }}// TODO: map via StringToStringVar: {{.Name}}
 			{{else if .Entity.IsEmpty }}// TODO: output-only field
-			{{else if .Entity.Enum }}cmd.Flags().Var(&{{$method.CamelName}}Req.{{.PascalName}}, "{{.KebabName}}", `{{.Summary | without "`"}}`)
+			{{else if .Entity.Enum }}cmd.Flags().Var(&{{$method.CamelName}}Req.{{.PascalName}}, "{{.KebabName}}", `{{.Summary | without "`" | trimSuffix "."}}. Supported values: {{template "printArray" .Entity.Enum}}`)
 			{{else}}cmd.Flags().{{template "arg-type" .Entity}}(&{{$method.CamelName}}Req.{{.PascalName}}, "{{.KebabName}}", {{$method.CamelName}}Req.{{.PascalName}}, `{{.Summary | without "`"}}`)
 			{{end}}
 		{{- end -}}