Allow to override database path through DIUN_DB env var

internal/config/config.go

@@ -11,6 +11,7 @@ import (
 	"regexp"
 
 	"github.com/crazy-max/diun/internal/model"
+	"github.com/crazy-max/diun/internal/utl"
 	"github.com/imdario/mergo"
 	"github.com/rs/zerolog/log"
 	"gopkg.in/yaml.v2"
@@ -88,6 +89,7 @@ func (cfg *Config) validate() error {
 		cfg.Db.Path = "/data/diun.db"
 	}
 
+	cfg.Db.Path = utl.GetEnv("DIUN_DB", cfg.Db.Path)
 	if cfg.Db.Path == "" {
 		return errors.New("database path is required")
 	}

internal/utl/utl.go

@@ -1,6 +1,7 @@
 package utl
 
 import (
+	"os"
 	"regexp"
 )
 
@@ -41,3 +42,12 @@ func IsExcluded(s string, excludes []string) bool {
 	}
 	return false
 }
+
+// GetEnv retrieves the value of the environment variable named by the key
+// or fallback if not found
+func GetEnv(key, fallback string) string {
+	if value, ok := os.LookupEnv(key); ok {
+		return value
+	}
+	return fallback
+}