Moved config to own module

internal/config/config.go

@@ -0,0 +1,55 @@
+package config
+
+import (
+	"flag"
+	"log/slog"
+	"os"
+	"strconv"
+)
+
+type Config struct {
+	Environment  string
+	Port         int
+	OTLPEndpoint string
+	DatabaseURL  string
+}
+
+func Load() *Config {
+	envFlag := flag.String("env", "development", "environment to use")
+	portFlag := flag.Int("port", 8080, "port to listen on")
+	otlpEndpointFlag := flag.String("otlp-endpoint", "localhost:4317", "otlp endpoint")
+	databaseUrlFlag := flag.String("database-url", "postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable", "database connection string")
+
+	flag.Parse()
+
+	cfg := &Config{
+		Environment:  *envFlag,
+		Port:         *portFlag,
+		OTLPEndpoint: *otlpEndpointFlag,
+		DatabaseURL:  *databaseUrlFlag,
+	}
+
+	assignStringFromEnv("DTTMR_ENVIRONMENT", &cfg.Environment)
+	assignIntFromEnv("DTTMR_PORT", &cfg.Port)
+	assignStringFromEnv("DTTMR_OTLP_ENDPOINT", &cfg.OTLPEndpoint)
+	assignStringFromEnv("DTTMR_DATABASE_URL", &cfg.DatabaseURL)
+
+	return cfg
+}
+
+func assignStringFromEnv(key string, target *string) {
+	if val, exists := os.LookupEnv(key); exists {
+		*target = val
+	}
+}
+
+func assignIntFromEnv(key string, target *int) {
+	if val, exists := os.LookupEnv(key); exists {
+		parsed, err := strconv.Atoi(val)
+		if err != nil {
+			slog.Error("Failed to parse environment variable", slog.String("var", key), slog.Any("error", err))
+		} else {
+			*target = parsed
+		}
+	}
+}