From 7310d022ad369ef1dda43af336698eaf838e72c6 Mon Sep 17 00:00:00 2001
From: chrislu <chris.lu@gmail.com>
Date: Sun, 28 Apr 2024 11:14:13 -0700
Subject: [PATCH] recursive struct to schema

---
 weed/mq/schema/schema_builder.go   | 16 ++++-----
 weed/mq/schema/struct_to_schema.go | 55 ++++++++++++++++++++++++++++++
 2 files changed, 63 insertions(+), 8 deletions(-)
 create mode 100644 weed/mq/schema/struct_to_schema.go

diff --git a/weed/mq/schema/schema_builder.go b/weed/mq/schema/schema_builder.go
index bcb46d2bb..cadf4f927 100644
--- a/weed/mq/schema/schema_builder.go
+++ b/weed/mq/schema/schema_builder.go
@@ -31,7 +31,7 @@ func (rtb *RecordTypeBuilder) Build() *schema_pb.RecordType {
 	return rtb.recordType
 }
 
-func (rtb *RecordTypeBuilder) addField(name string, scalarType *schema_pb.Type) *RecordTypeBuilder {
+func (rtb *RecordTypeBuilder) setField(name string, scalarType *schema_pb.Type) *RecordTypeBuilder {
 	rtb.recordType.Fields = append(rtb.recordType.Fields, &schema_pb.Field{
 		Name: name,
 		Type: scalarType,
@@ -40,25 +40,25 @@ func (rtb *RecordTypeBuilder) addField(name string, scalarType *schema_pb.Type)
 }
 
 func (rtb *RecordTypeBuilder) SetBoolField(name string) *RecordTypeBuilder {
-	return rtb.addField(name, TypeBoolean)
+	return rtb.setField(name, TypeBoolean)
 }
 func (rtb *RecordTypeBuilder) SetIntegerField(name string) *RecordTypeBuilder {
-	return rtb.addField(name, TypeInteger)
+	return rtb.setField(name, TypeInteger)
 }
 func (rtb *RecordTypeBuilder) SetLongField(name string) *RecordTypeBuilder {
-	return rtb.addField(name, TypeLong)
+	return rtb.setField(name, TypeLong)
 }
 func (rtb *RecordTypeBuilder) SetFloatField(name string) *RecordTypeBuilder {
-	return rtb.addField(name, TypeFloat)
+	return rtb.setField(name, TypeFloat)
 }
 func (rtb *RecordTypeBuilder) SetDoubleField(name string) *RecordTypeBuilder {
-	return rtb.addField(name, TypeDouble)
+	return rtb.setField(name, TypeDouble)
 }
 func (rtb *RecordTypeBuilder) SetBytesField(name string) *RecordTypeBuilder {
-	return rtb.addField(name, TypeBytes)
+	return rtb.setField(name, TypeBytes)
 }
 func (rtb *RecordTypeBuilder) SetStringField(name string) *RecordTypeBuilder {
-	return rtb.addField(name, TypeString)
+	return rtb.setField(name, TypeString)
 }
 
 func (rtb *RecordTypeBuilder) SetRecordField(name string, recordTypeBuilder *RecordTypeBuilder) *RecordTypeBuilder {
diff --git a/weed/mq/schema/struct_to_schema.go b/weed/mq/schema/struct_to_schema.go
new file mode 100644
index 000000000..bdd3e2465
--- /dev/null
+++ b/weed/mq/schema/struct_to_schema.go
@@ -0,0 +1,55 @@
+package schema
+
+import (
+	"github.com/seaweedfs/seaweedfs/weed/pb/schema_pb"
+	"reflect"
+)
+
+func StructToSchema(instance any) *RecordTypeBuilder {
+	rtb := NewRecordTypeBuilder()
+	myType := reflect.TypeOf(instance)
+	for i := 0; i < myType.NumField(); i++ {
+		field := myType.Field(i)
+		fieldType := field.Type
+		fieldName := field.Name
+		schemaField := reflectTypeToSchemaType(fieldType)
+		if schemaField == nil {
+			continue
+		}
+		rtb.setField(fieldName, schemaField)
+	}
+	return rtb
+}
+
+func reflectTypeToSchemaType(t reflect.Type) *schema_pb.Type {
+	switch t.Kind() {
+	case reflect.Bool:
+		return TypeBoolean
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32:
+		return TypeInteger
+	case reflect.Int64:
+		return TypeLong
+	case reflect.Float32:
+		return TypeFloat
+	case reflect.Float64:
+		return TypeDouble
+	case reflect.String:
+		return TypeString
+	case reflect.Slice:
+		switch t.Elem().Kind() {
+		case reflect.Uint8:
+			return TypeBytes
+		default:
+			if st := reflectTypeToSchemaType(t.Elem()); st != nil {
+				return &schema_pb.Type{
+					Kind: &schema_pb.Type_ListType{
+						ListType: &schema_pb.ListType{
+							ElementType: st,
+						},
+					},
+				}
+			}
+		}
+	}
+	return nil
+}