Support SnakeCase style environment name

configor.go

@@ -113,20 +113,26 @@ func processTags(config interface{}, prefix ...string) error {
 
 	configType := configValue.Type()
 	for i := 0; i < configType.NumField(); i++ {
-		fieldStruct := configType.Field(i)
-		field := configValue.Field(i)
+		var (
+			envNames    []string
+			fieldStruct = configType.Field(i)
+			field       = configValue.Field(i)
+			envName     = fieldStruct.Tag.Get("env") // read configuration from shell env
+		)
 
-		// read configuration from shell env
-		var envName = fieldStruct.Tag.Get("env")
 		if envName == "" {
-			envName = strings.ToUpper(strings.Join(append(prefix, fieldStruct.Name), "_"))
+			envNames = append(envNames, strings.Join(append(prefix, fieldStruct.Name), "_"))
+			envNames = append(envNames, strings.ToUpper(strings.Join(append(prefix, fieldStruct.Name), "_")))
+		} else {
+			envNames = []string{envName}
 		}
 
-		if envName != "" {
-			if value := os.Getenv(envName); value != "" {
+		for _, env := range envNames {
+			if value := os.Getenv(env); value != "" {
 				if err := yaml.Unmarshal([]byte(value), field.Addr().Interface()); err != nil {
 					return err
 				}
+				break
 			}
 		}
 

configor_test.go

@@ -10,8 +10,8 @@ import (
 
 	"gopkg.in/yaml.v2"
 
-	"github.com/jinzhu/configor"
 	"github.com/BurntSushi/toml"
+	"github.com/jinzhu/configor"
 )
 
 type Anonymous struct {
@@ -274,6 +274,33 @@ func TestResetPrefixToBlank(t *testing.T) {
 	}
 }
 
+func TestResetPrefixToBlank2(t *testing.T) {
+	config := generateDefaultConfig()
+
+	if bytes, err := json.Marshal(config); err == nil {
+		if file, err := ioutil.TempFile("/tmp", "configor"); err == nil {
+			defer file.Close()
+			defer os.Remove(file.Name())
+			file.Write(bytes)
+			var result Config
+			os.Setenv("CONFIGOR_ENV_PREFIX", "-")
+			os.Setenv("APPName", "config2")
+			os.Setenv("DB_Name", "db_name")
+			defer os.Setenv("CONFIGOR_ENV_PREFIX", "")
+			defer os.Setenv("APPName", "")
+			defer os.Setenv("DB_Name", "")
+			configor.Load(&result, file.Name())
+
+			var defaultConfig = generateDefaultConfig()
+			defaultConfig.APPName = "config2"
+			defaultConfig.DB.Name = "db_name"
+			if !reflect.DeepEqual(result, defaultConfig) {
+				t.Errorf("result should equal to original configuration")
+			}
+		}
+	}
+}
+
 func TestReadFromEnvironmentWithSpecifiedEnvName(t *testing.T) {
 	config := generateDefaultConfig()