From 33380e2124e4844200e93ebf4ef59afda4d90215 Mon Sep 17 00:00:00 2001
From: Tim Wundenberg <tim@wundenbergs.de>
Date: Wed, 2 Oct 2024 18:27:16 +0200
Subject: [PATCH] chore: parametrize port and prometheus #181

---
 main.go                                   | 19 +++++++++++----
 types/{settings.go => server_settings.go} | 28 +++++++++++++++--------
 2 files changed, 32 insertions(+), 15 deletions(-)
 rename types/{settings.go => server_settings.go} (70%)

diff --git a/main.go b/main.go
index dfdfe4c..ecaae18 100644
--- a/main.go
+++ b/main.go
@@ -48,15 +48,20 @@ func run(ctx context.Context, env func(string) string) {
 	utils.MustRunMigrations(db, "")
 
 	// init servers
-	prometheusServer := &http.Server{
-		Addr:    ":8081",
-		Handler: promhttp.Handler(),
+
+	var prometheusServer *http.Server
+	if serverSettings.PrometheusEnabled {
+		prometheusServer := &http.Server{
+			Addr:    ":8081",
+			Handler: promhttp.Handler(),
+		}
+		go startServer(prometheusServer)
 	}
+
 	httpServer := &http.Server{
-		Addr:    ":8080",
+		Addr:    ":" + serverSettings.Port,
 		Handler: handler.GetHandler(db, serverSettings),
 	}
-	go startServer(prometheusServer)
 	go startServer(httpServer)
 
 	// graceful shutdown
@@ -76,6 +81,10 @@ func startServer(s *http.Server) {
 
 func shutdownServer(s *http.Server, ctx context.Context, wg *sync.WaitGroup) {
 	defer wg.Done()
+	if s == nil {
+		return
+	}
+
 	<-ctx.Done()
 	shutdownCtx := context.Background()
 	shutdownCtx, cancel := context.WithTimeout(shutdownCtx, 10*time.Second)
diff --git a/types/settings.go b/types/server_settings.go
similarity index 70%
rename from types/settings.go
rename to types/server_settings.go
index d41ad0e..0ca858f 100644
--- a/types/settings.go
+++ b/types/server_settings.go
@@ -6,6 +6,9 @@ import (
 )
 
 type ServerSettings struct {
+	Port              string
+	PrometheusEnabled bool
+
 	BaseUrl     string
 	Environment string
 	DbPath      string
@@ -23,11 +26,6 @@ type SmtpSettings struct {
 
 func NewServerSettingsFromEnv(env func(string) string) *ServerSettings {
 
-	dbPath := env("DB_PATH")
-	if dbPath == "" {
-		dbPath = "./data.db"
-	}
-
 	var smtp *SmtpSettings
 	if env("SMTP_ENABLED") == "true" {
 		smtp = &SmtpSettings{
@@ -60,20 +58,30 @@ func NewServerSettingsFromEnv(env func(string) string) *ServerSettings {
 	}
 
 	settings := &ServerSettings{
-		BaseUrl:     env("BASE_URL"),
-		Environment: env("ENVIRONMENT"),
-		Smtp:        smtp,
+		Port:              env("PORT"),
+		PrometheusEnabled: env("PROMETHEUS_ENABLED") == "true",
+		BaseUrl:           env("BASE_URL"),
+		DbPath:            env("DB_PATH"),
+		Environment:       env("ENVIRONMENT"),
+		Smtp:              smtp,
+	}
+
+	if settings.DbPath == "" {
+		settings.DbPath = "./data.db"
 	}
 
 	if settings.BaseUrl == "" {
 		log.Fatal("BASE_URL must be set")
 	}
+	if settings.Port == "" {
+		log.Fatal("PORT must be set")
+	}
 	if settings.Environment == "" {
 		log.Fatal("ENVIRONMENT must be set")
 	}
 
-	if settings.Environment == "prod" && settings.Smtp == nil {
-		log.Fatal("SMTP must be enabled in production")
+	if settings.Environment == "prod" && (settings.Smtp == nil || !settings.PrometheusEnabled) {
+		log.Fatal("SMTP and Prometheus must be enabled in production")
 	}
 
 	slog.Info("BASE_URL is " + settings.BaseUrl)