support protobuf option style config

Author: chaokunyang

compiler/README.md

@@ -220,6 +220,46 @@ message Example {
 }
 ```
 
+### Fory Extension Options
+
+FDL supports protobuf-style extension options using the `(fory)` prefix:
+
+**File-level options:**
+
+```fdl
+option (fory).use_record_for_java_message = true;
+option (fory).polymorphism = true;
+```
+
+**Message/Enum options:**
+
+```fdl
+message MyMessage {
+    option (fory).id = 100;
+    option (fory).compatible = true;
+    option (fory).use_record_for_java = true;
+    string name = 1;
+}
+
+enum Status {
+    option (fory).id = 101;
+    UNKNOWN = 0;
+    ACTIVE = 1;
+}
+```
+
+**Field options:**
+
+```fdl
+message Example {
+    MyType friend = 1 [(fory).ref = true];
+    string nickname = 2 [(fory).nullable = true];
+    MyType data = 3 [(fory).ref = true, (fory).nullable = true];
+}
+```
+
+See `extension/fory_options.proto` for the complete list of available options.
+
 ## Architecture
 
 ```

compiler/extension/fory_options.proto

@@ -0,0 +1,152 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// Fory Options for FDL (Fory Definition Language)
+// @author: chaokunyang
+//
+// This file defines custom options that can be used in FDL schemas
+// to control Fory serialization behavior. Copy this file into your
+// project to use these options.
+//
+// Usage Examples:
+//
+// File-level options:
+//   option (fory).use_record_for_java_message = true;
+//
+// Message options:
+//   message MyMessage {
+//     option (fory).id = 100;
+//     option (fory).compatible = true;
+//     option (fory).use_record_for_java = true;
+//   }
+//
+// Enum options:
+//   enum Status {
+//     option (fory).id = 101;
+//   }
+//
+// Field options:
+//   message Example {
+//     MyType field = 1 [(fory).ref = true, (fory).nullable = true];
+//   }
+
+syntax = "proto3";
+
+package fory;
+
+import "google/protobuf/descriptor.proto";
+
+// ===========================================================================
+// File-Level Options
+// ===========================================================================
+// These options apply to the entire FDL file and affect all generated code.
+
+message ForyFileOptions {
+  // Generate Java records instead of classes for all messages in this file.
+  // Only applies to Java code generation.
+  // Default: false (generates traditional POJOs)
+  optional bool use_record_for_java_message = 1;
+
+  // Enable polymorphism support for all types in this file.
+  // When true, type metadata is included in serialization for polymorphic dispatch.
+  // Default: false
+  optional bool polymorphism = 2;
+}
+
+extend google.protobuf.FileOptions {
+  optional ForyFileOptions fory = 50001;
+}
+
+// ===========================================================================
+// Message-Level Options
+// ===========================================================================
+// These options apply to individual message definitions.
+
+message ForyMessageOptions {
+  // Unique type ID for cross-language registration.
+  // Used for efficient type lookup during deserialization.
+  // Must be a positive integer unique within the schema.
+  // If not specified, namespace-based registration is used.
+  optional int32 id = 1;
+
+  // Enable schema compatibility mode for this message.
+  // When true, fields can be added/removed without breaking compatibility.
+  // Default: false (strict schema matching)
+  optional bool compatible = 2;
+
+  // Generate a Java record instead of a class for this specific message.
+  // Overrides file-level use_record_for_java_message setting.
+  // Only applies to Java code generation.
+  optional bool use_record_for_java = 3;
+
+  // Mark this message as deprecated.
+  // Generates appropriate deprecation annotations in target languages.
+  optional bool deprecated = 4;
+
+  // Custom namespace for type registration.
+  // Overrides the default package-based namespace.
+  optional string namespace = 5;
+}
+
+extend google.protobuf.MessageOptions {
+  optional ForyMessageOptions fory = 50001;
+}
+
+// ===========================================================================
+// Enum-Level Options
+// ===========================================================================
+// These options apply to individual enum definitions.
+
+message ForyEnumOptions {
+  // Unique type ID for cross-language registration.
+  // Used for efficient type lookup during deserialization.
+  // Must be a positive integer unique within the schema.
+  optional int32 id = 1;
+
+  // Mark this enum as deprecated.
+  optional bool deprecated = 2;
+}
+
+extend google.protobuf.EnumOptions {
+  optional ForyEnumOptions fory = 50001;
+}
+
+// ===========================================================================
+// Field-Level Options
+// ===========================================================================
+// These options apply to individual field definitions.
+
+message ForyFieldOptions {
+  // Enable reference tracking for this field.
+  // When true, Fory tracks object references to handle:
+  // - Circular references (e.g., tree structures with parent pointers)
+  // - Shared references (same object referenced multiple times)
+  // Default: false
+  optional bool ref = 1;
+
+  // Mark this field as nullable.
+  // When true, the field can be null/None/nil.
+  // Default: false (field must have a value)
+  optional bool nullable = 2;
+
+  // Mark this field as deprecated.
+  optional bool deprecated = 3;
+}
+
+extend google.protobuf.FieldOptions {
+  optional ForyFieldOptions fory = 50001;
+}

compiler/fory_compiler/parser/ast.py

@@ -108,6 +108,7 @@ class Field:
     number: int
     optional: bool = False
     ref: bool = False
+    options: dict = field(default_factory=dict)
     line: int = 0
     column: int = 0
 
@@ -118,7 +119,8 @@ def __repr__(self) -> str:
         if self.ref:
             modifiers.append("ref")
         mod_str = " ".join(modifiers) + " " if modifiers else ""
-        return f"Field({mod_str}{self.field_type} {self.name} = {self.number})"
+        opts_str = f" [{self.options}]" if self.options else ""
+        return f"Field({mod_str}{self.field_type} {self.name} = {self.number}{opts_str})"
 
 
 @dataclass
@@ -155,15 +157,17 @@ class Message:
     fields: List[Field] = field(default_factory=list)
     nested_messages: List["Message"] = field(default_factory=list)
     nested_enums: List["Enum"] = field(default_factory=list)
+    options: dict = field(default_factory=dict)
     line: int = 0
     column: int = 0
 
     def __repr__(self) -> str:
-        id_str = f" @{self.type_id}" if self.type_id is not None else ""
+        id_str = f" [id={self.type_id}]" if self.type_id is not None else ""
         nested_str = ""
         if self.nested_messages or self.nested_enums:
             nested_str = f", nested={len(self.nested_messages)}msg+{len(self.nested_enums)}enum"
-        return f"Message({self.name}{id_str}, fields={self.fields}{nested_str})"
+        opts_str = f", options={len(self.options)}" if self.options else ""
+        return f"Message({self.name}{id_str}, fields={self.fields}{nested_str}{opts_str})"
 
     def get_nested_type(self, name: str) -> Optional[Union["Message", "Enum"]]:
         """Look up a nested type by name."""
@@ -183,12 +187,14 @@ class Enum:
     name: str
     type_id: Optional[int]
     values: List[EnumValue] = field(default_factory=list)
+    options: dict = field(default_factory=dict)
     line: int = 0
     column: int = 0
 
     def __repr__(self) -> str:
-        id_str = f" @{self.type_id}" if self.type_id is not None else ""
-        return f"Enum({self.name}{id_str}, values={self.values})"
+        id_str = f" [id={self.type_id}]" if self.type_id is not None else ""
+        opts_str = f", options={len(self.options)}" if self.options else ""
+        return f"Enum({self.name}{id_str}, values={self.values}{opts_str})"
 
 
 @dataclass

compiler/fory_compiler/parser/lexer.py

@@ -53,6 +53,8 @@ class TokenType(Enum):
     RBRACE = auto()  # }
     LBRACKET = auto()  # [
     RBRACKET = auto()  # ]
+    LPAREN = auto()  # (
+    RPAREN = auto()  # )
     LANGLE = auto()  # <
     RANGLE = auto()  # >
     SEMI = auto()  # ;
@@ -113,6 +115,8 @@ class Lexer:
         "}": TokenType.RBRACE,
         "[": TokenType.LBRACKET,
         "]": TokenType.RBRACKET,
+        "(": TokenType.LPAREN,
+        ")": TokenType.RPAREN,
         "<": TokenType.LANGLE,
         ">": TokenType.RANGLE,
         ";": TokenType.SEMI,