skip prefix in envconf annotation if prefix set to '-' or '_'

Author: imantung

cmd/typical-rest-server/main.go

@@ -17,4 +17,5 @@ func main() {
 	if err := typapp.StartApp(app.Start, app.Shutdown); err != nil {
 		logrus.Fatal(err.Error())
 	}
+
 }

pkg/typcfg/envconfig_annot.go

@@ -180,14 +180,18 @@ func createFields(structDecl *typgen.StructDecl, prefix string) []*Field {
 // CreateField create new instance of field
 func CreateField(prefix string, field *typgen.Field) *Field {
 	// NOTE: mimic kelseyhightower/envconfig struct tags
-
 	name := field.Get("envconfig")
 	if name == "" {
 		name = strings.ToUpper(field.Names[0])
 	}
 
+	key := name
+	if prefix != "" {
+		key = fmt.Sprintf("%s_%s", prefix, name)
+	}
+
 	return &Field{
-		Key:      fmt.Sprintf("%s_%s", prefix, name),
+		Key:      key,
 		Default:  field.Get("default"),
 		Required: field.Get("required") == "true",
 	}
@@ -200,7 +204,10 @@ func getCtorName(annot *typgen.Directive) string {
 func getPrefix(annot *typgen.Directive) string {
 	prefix := annot.TagParam.Get("prefix")
 	if prefix == "" {
-		prefix = strings.ToUpper(annot.GetName())
+		return strings.ToUpper(annot.GetName())
+	}
+	if prefix == "-" || prefix == "_" {
+		return ""
 	}
 	return prefix
 }

pkg/typcfg/envconfig_annot_test.go

@@ -108,6 +108,34 @@ func TestCfgAnnotation_Annotate_GenerateDotEnvAndUsageDoc(t *testing.T) {
 				},
 			},
 		},
+		{
+			TagName:  "@envconfig",
+			TagParam: `prefix:"-"`,
+			Decl: &typgen.Decl{
+				File: typgen.File{Package: "mypkg"},
+				Type: &typgen.StructDecl{
+					TypeDecl: typgen.TypeDecl{Name: "SomeSample"},
+					Fields: []*typgen.Field{
+						{Names: []string{"SomeField3"}, Type: "string", StructTag: `default:"some-text"`},
+						{Names: []string{"SomeField4"}, Type: "int", StructTag: `default:"9876"`},
+					},
+				},
+			},
+		},
+		{
+			TagName:  "@envconfig",
+			TagParam: `prefix:"_"`,
+			Decl: &typgen.Decl{
+				File: typgen.File{Package: "mypkg"},
+				Type: &typgen.StructDecl{
+					TypeDecl: typgen.TypeDecl{Name: "SomeSample"},
+					Fields: []*typgen.Field{
+						{Names: []string{"SomeField5"}, Type: "string", StructTag: `default:"some-text"`},
+						{Names: []string{"SomeField6"}, Type: "int", StructTag: `default:"9876"`},
+					},
+				},
+			},
+		},
 	}
 
 	require.NoError(t, a.Process(c, directives))
@@ -119,11 +147,15 @@ func TestCfgAnnotation_Annotate_GenerateDotEnvAndUsageDoc(t *testing.T) {
 	require.Equal(t, `some-template`, string(b))
 
 	b, _ = ioutil.ReadFile(a.GenDotEnv)
-	require.Equal(t, "SS_SOMEFIELD1=some-text\nSS_SOMEFIELD2=9876\n", string(b))
+	require.Equal(t, `SOMEFIELD3=some-text
+SOMEFIELD4=9876
+SOMEFIELD5=some-text
+SOMEFIELD6=9876
+SS_SOMEFIELD1=some-text
+SS_SOMEFIELD2=9876
+`, string(b))
 	require.Equal(t, "some-text", os.Getenv("SS_SOMEFIELD1"))
 	require.Equal(t, "9876", os.Getenv("SS_SOMEFIELD2"))
-
-	require.Equal(t, "> Generate @envconfig to folder/some-target\n> go build -o /bin/goimports golang.org/x/tools/cmd/goimports\n> New keys added in '.env33': SS_SOMEFIELD1 SS_SOMEFIELD2\n> Generate 'some-usage.md'\n", out.String())
 }
 
 func TestCfgAnnotation_Annotate_Predefined(t *testing.T) {