223 lines
10 KiB
Python
223 lines
10 KiB
Python
from enum import IntEnum
|
||
import struct
|
||
import json
|
||
import gzip
|
||
from typing import Optional, Union, Dict, Any, List
|
||
|
||
|
||
# -------------------------- 协议常量定义 --------------------------
|
||
class ProtocolConst:
|
||
PROTOCOL_VERSION = 0b0001 # 协议版本v1
|
||
HEADER_SIZE = 8 # 头部固定字节数（字节1~字节8）
|
||
MAX_BODY_SIZE = 1024 * 1024 * 10 # 最大包体大小（10MB，防止内存溢出）
|
||
STRING_ENCODING = "utf-8" # 字符串默认编码（统一编码格式，避免乱码）
|
||
|
||
|
||
# -------------------------- 枚举定义（业务约定） --------------------------
|
||
class MessageType(IntEnum):
|
||
"""消息类型（4位，字节1高4位）"""
|
||
PING = 0b0000 # 心跳
|
||
AUDIO_DATA = 0b0001 # 纯音频数据(pcm)
|
||
TEXT_MESSAGE = 0b0010 # 纯文本消息
|
||
AUDIO_TEXT_MIX = 0b0011 # 音频+文本混合数据
|
||
CONTROL_CMD = 0b0100 # 控制指令（暂停/继续等）
|
||
|
||
class SerializationType(IntEnum):
|
||
"""序列化方式（4位，字节2高4位）"""
|
||
RAW = 0b0000 # 原始二进制（音频等）
|
||
JSON = 0b0001 # JSON格式（文本/指令）
|
||
STRING = 0b0010 # 直接字符串（纯文本，UTF-8编码，无JSON包装）🔴新增类型
|
||
|
||
class CompressionType(IntEnum):
|
||
"""压缩方式（4位，字节2低4位）"""
|
||
NONE = 0b0000 # 无压缩
|
||
GZIP = 0b0001 # gzip压缩
|
||
|
||
class ControlCommand(IntEnum):
|
||
"""控制指令类型（配合MessageType.CONTROL_CMD使用）"""
|
||
HEARTBEAT = 0b0001 # 心跳响应
|
||
PAUSE = 0b0010 # 暂停
|
||
RESUME = 0b0011 # 继续
|
||
STOP = 0b0100 # 停止
|
||
|
||
# -------------------------- 协议工具类 --------------------------
|
||
class ProtocolCodec:
|
||
@staticmethod
|
||
def pack(
|
||
msg_type: MessageType,
|
||
body: Union[bytes, str, Dict[str, Any], List[Any]],
|
||
serialization: Optional[SerializationType] = None,
|
||
compression: CompressionType = CompressionType.NONE
|
||
) -> bytes:
|
||
"""
|
||
封装协议包（头部 + 包体）
|
||
:param msg_type: 消息类型
|
||
:param body: 包体数据（bytes/str/dict/list）
|
||
:param serialization: 序列化方式（None时自动推导）
|
||
:param compression: 压缩方式
|
||
:return: 完整协议包（bytes）
|
||
"""
|
||
# 1. 自动推导序列化方式（优化：纯文本消息自动用STRING，复杂结构用JSON）🔴修改推导逻辑
|
||
if serialization is None:
|
||
if msg_type == MessageType.AUDIO_DATA:
|
||
serialization = SerializationType.RAW
|
||
elif msg_type == MessageType.TEXT_MESSAGE: # 纯文本消息→STRING
|
||
serialization = SerializationType.STRING
|
||
elif msg_type in (MessageType.CONTROL_CMD, MessageType.AUDIO_TEXT_MIX): # 复杂结构→JSON
|
||
serialization = SerializationType.JSON
|
||
else:
|
||
raise ValueError(f"不支持的消息类型：{msg_type}")
|
||
|
||
# 2. 序列化包体（新增STRING类型处理）🔴新增分支
|
||
serialized_body: bytes
|
||
if serialization == SerializationType.RAW:
|
||
if not isinstance(body, bytes):
|
||
raise TypeError("RAW序列化要求body必须是bytes类型")
|
||
serialized_body = body
|
||
elif serialization == SerializationType.STRING:
|
||
if not isinstance(body, str):
|
||
raise TypeError("STRING序列化要求body必须是str类型")
|
||
serialized_body = body.encode(ProtocolConst.STRING_ENCODING) # 直接UTF-8编码，无JSON包装
|
||
elif serialization == SerializationType.JSON:
|
||
if isinstance(body, str):
|
||
serialized_body = body.encode(ProtocolConst.STRING_ENCODING)
|
||
elif isinstance(body, (dict, list)):
|
||
serialized_body = json.dumps(body, ensure_ascii=False, separators=(',', ':')).encode(ProtocolConst.STRING_ENCODING)
|
||
else:
|
||
raise TypeError("JSON序列化要求body必须是str/dict/list类型")
|
||
else:
|
||
raise ValueError(f"不支持的序列化方式：{serialization}")
|
||
|
||
# 3. 压缩包体（不变）
|
||
compressed_body: bytes
|
||
if compression == CompressionType.GZIP:
|
||
compressed_body = gzip.compress(serialized_body)
|
||
elif compression == CompressionType.NONE:
|
||
compressed_body = serialized_body
|
||
else:
|
||
raise ValueError(f"不支持的压缩方式：{compression}")
|
||
|
||
# 4. 校验包体大小（不变）
|
||
body_len = len(compressed_body)
|
||
if body_len > ProtocolConst.MAX_BODY_SIZE:
|
||
raise OverflowError(f"包体过大（{body_len}字节），最大支持{ProtocolConst.MAX_BODY_SIZE}字节")
|
||
|
||
# 5. 构造头部（不变）
|
||
byte1 = (msg_type.value << 4) | 0x00 # 消息类型(4位) + 保留位1(4位)
|
||
byte2 = (serialization.value << 4) | (compression.value & 0x0F) # 序列化(4位) + 压缩(4位)
|
||
byte3_4 = struct.pack(">H", ProtocolConst.PROTOCOL_VERSION) # 协议版本(16位)
|
||
byte5_8 = struct.pack(">I", body_len) # 包体长度(32位)
|
||
header = bytes([byte1, byte2]) + byte3_4 + byte5_8
|
||
assert len(header) == ProtocolConst.HEADER_SIZE, f"头部长度错误：实际{len(header)}字节，预期{ProtocolConst.HEADER_SIZE}字节"
|
||
|
||
return header + compressed_body
|
||
|
||
@staticmethod
|
||
def unpack(packet: bytes) -> tuple[MessageType, SerializationType, CompressionType, Any]:
|
||
"""
|
||
解析协议包
|
||
:param packet: 完整协议包（头部 + 包体）
|
||
:return: (消息类型, 序列化方式, 压缩方式, 原始包体数据)
|
||
"""
|
||
# 1. 校验包长度（不变）
|
||
if len(packet) < ProtocolConst.HEADER_SIZE:
|
||
raise ValueError(f"包长度过短（{len(packet)}字节），至少需要{ProtocolConst.HEADER_SIZE}字节头部")
|
||
|
||
# 2. 解析头部（不变）
|
||
header = packet[:ProtocolConst.HEADER_SIZE]
|
||
body = packet[ProtocolConst.HEADER_SIZE:]
|
||
byte1 = header[0]
|
||
byte2 = header[1]
|
||
|
||
msg_type = MessageType((byte1 >> 4) & 0x0F)
|
||
serialization = SerializationType((byte2 >> 4) & 0x0F)
|
||
compression = CompressionType(byte2 & 0x0F)
|
||
version = struct.unpack(">H", header[2:4])[0]
|
||
body_len = struct.unpack(">I", header[4:8])[0]
|
||
|
||
if version != ProtocolConst.PROTOCOL_VERSION:
|
||
raise ValueError(f"协议版本不匹配：收到v{version}，支持v{ProtocolConst.PROTOCOL_VERSION}")
|
||
if len(body) != body_len:
|
||
raise ValueError(f"包体长度不匹配：头部声明{body_len}字节，实际{len(body)}字节")
|
||
|
||
# 3. 解压包体（不变）
|
||
decompressed_body: bytes
|
||
if compression == CompressionType.GZIP:
|
||
try:
|
||
decompressed_body = gzip.decompress(body)
|
||
except Exception as e:
|
||
raise ValueError(f"GZIP解压失败：{str(e)}")
|
||
elif compression == CompressionType.NONE:
|
||
decompressed_body = body
|
||
else:
|
||
raise ValueError(f"不支持的压缩方式：{compression}")
|
||
|
||
# 4. 反序列化包体（新增STRING类型处理）🔴新增分支
|
||
original_body: Any
|
||
if serialization == SerializationType.RAW:
|
||
original_body = decompressed_body
|
||
elif serialization == SerializationType.STRING:
|
||
try:
|
||
original_body = decompressed_body.decode(ProtocolConst.STRING_ENCODING) # 直接UTF-8解码，无JSON解析
|
||
except UnicodeDecodeError:
|
||
raise ValueError(f"STRING反序列化失败：{ProtocolConst.STRING_ENCODING}解码错误")
|
||
elif serialization == SerializationType.JSON:
|
||
try:
|
||
original_body = json.loads(decompressed_body.decode(ProtocolConst.STRING_ENCODING))
|
||
except UnicodeDecodeError:
|
||
raise ValueError(f"JSON反序列化失败：{ProtocolConst.STRING_ENCODING}解码错误")
|
||
except json.JSONDecodeError:
|
||
raise ValueError("JSON反序列化失败：格式错误")
|
||
else:
|
||
raise ValueError(f"不支持的序列化方式：{serialization}")
|
||
|
||
return msg_type, serialization, compression, original_body
|
||
|
||
|
||
# -------------------------- 使用示例（新增纯字符串消息测试） --------------------------
|
||
if __name__ == "__main__":
|
||
# 示例1：纯文本消息（自动用STRING序列化，无JSON包装）🔴测试新增类型
|
||
text_body = "你好，这是纯字符串消息（无JSON）"
|
||
text_packet = ProtocolCodec.pack(
|
||
msg_type=MessageType.TEXT_MESSAGE,
|
||
body=text_body,
|
||
compression=CompressionType.NONE
|
||
)
|
||
print(f"纯文本消息包长度：{len(text_packet)}字节")
|
||
msg_type1, ser1, comp1, body1 = ProtocolCodec.unpack(text_packet)
|
||
print(f"解析结果：类型={msg_type1.name}，序列化={ser1.name}，压缩={comp1.name}，内容={body1}\n")
|
||
|
||
# 示例2：控制指令（JSON序列化，复杂结构）
|
||
control_body = {"cmd": ControlCommand.HEARTBEAT.value, "timestamp": 1699999999}
|
||
control_packet = ProtocolCodec.pack(
|
||
msg_type=MessageType.CONTROL_CMD,
|
||
body=control_body,
|
||
compression=CompressionType.NONE
|
||
)
|
||
print(f"控制指令包长度：{len(control_packet)}字节")
|
||
msg_type2, ser2, comp2, body2 = ProtocolCodec.unpack(control_packet)
|
||
print(f"解析结果：类型={msg_type2.name}，序列化={ser2.name}，压缩={comp2.name}，内容={body2}\n")
|
||
|
||
# 示例3：音频数据（RAW序列化）
|
||
audio_body = b"\x00\x01\x02\x03\x04\x05" * 100 # 模拟PCM数据
|
||
audio_packet = ProtocolCodec.pack(
|
||
msg_type=MessageType.AUDIO_DATA,
|
||
body=audio_body,
|
||
compression=CompressionType.NONE
|
||
)
|
||
print(f"音频数据包长度：{len(audio_packet)}字节")
|
||
msg_type3, ser3, comp3, body3 = ProtocolCodec.unpack(audio_packet)
|
||
print(f"解析结果：类型={msg_type3.name}，序列化={ser3.name}，压缩={comp3.name}，数据长度={len(body3)}字节\n")
|
||
|
||
# 示例4：混合数据（JSON序列化）
|
||
mix_body = {
|
||
"audio_data": list(audio_body[:10]),
|
||
"text_content": "混合数据仍用JSON"
|
||
}
|
||
mix_packet = ProtocolCodec.pack(
|
||
msg_type=MessageType.AUDIO_TEXT_MIX,
|
||
body=mix_body
|
||
)
|
||
print(f"混合数据包长度：{len(mix_packet)}字节")
|
||
msg_type4, ser4, comp4, body4 = ProtocolCodec.unpack(mix_packet)
|
||
print(f"解析结果：类型={msg_type4.name}，序列化={ser4.name}，压缩={comp4.name}，内容={body4}") |