[add] initial commit

config/environment.go

@@ -0,0 +1,51 @@
+package config
+
+import (
+	"gelvin/app/application"
+	"os"
+)
+
+const EnvPrefix = "GELVIN_"
+
+type environment struct {
+	Mode    application.Mode
+	UrlRoot string
+	Version application.Version
+}
+
+func Environment() environment {
+
+	var mode application.Mode
+	switch getEnv("MODE") {
+	case "TEST":
+		mode = application.Test
+	case "PRODUCTION":
+		mode = application.Production
+	default:
+		mode = application.Debug
+	}
+
+	var urlRoot string
+	if urlRoot = getEnv("URL_ROOT"); urlRoot == "" {
+		urlRoot = "/"
+	}
+
+	version := parseVersion(getEnv("API_VERSION"))
+	return environment{
+		Mode:    mode,
+		UrlRoot: urlRoot,
+		Version: version,
+	}
+}
+
+func getEnv(key string) string {
+	return os.Getenv(EnvPrefix + key)
+}
+
+func parseVersion(s string) application.Version {
+	version := application.Version{Major: 1}
+	if s != "" {
+		// TODO
+	}
+	return version
+}