neue Datei: .gitignore

neue Datei:     README.md
	neue Datei:     pyproject.toml
	neue Datei:     src/jeb_utils/__init__.py
	neue Datei:     src/jeb_utils/auth_utils.py
	neue Datei:     src/jeb_utils/crypto_utils.py
	neue Datei:     src/jeb_utils/exceptions.py
	neue Datei:     src/jeb_utils/jeb_utils.py
	neue Datei:     src/jeb_utils/jebp_utils.py
	neue Datei:     src/jeb_utils/utils.py

src/jeb_utils/jebp_utils.py

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+import asyncio
+from cryptography.hazmat.primitives.ciphers.aead import AESGCM
+import io
+from . import utils
+from typing import Sequence
+
+__all__ = [
+    'MessageFormatError',
+    'sendmsg',
+    'readmsg',
+    'pack_fields',
+    'unpack_fields',
+]
+
+_MSG_START_BYTE = b'\x01'
+
+class MessageFormatError(Exception): ...
+
+async def sendmsg(m: bytes, writer: asyncio.StreamWriter, aesgcm: AESGCM = None, aesnonce: bytes = None, send_headers: bool = True, _content_length: int = None, start_byte: bytes = _MSG_START_BYTE):
+    '''
+    Sends a message.
+    
+    :param m: The message
+    :type m: bytes
+    :param writer: The writer
+    :type writer: asyncio.StreamWriter
+    :param aesgcm: AESGCM
+    :type aesgcm: AESGCM
+    :param aesnonce: The nonce
+    :type aesnonce: bytes
+    :param send_headers: Controls whether the protocol headers are sent.
+    :type send_headers: bool
+    :param _content_length: The content length. If ``None``, the content length will be calculated automatically.
+    :type _content_length: int
+    :param start_byte: The start byte.
+    :type start_byte: bytes
+    '''
+    if type(m) == str:  
+        m = m.encode()
+    if aesgcm:
+        m = aesgcm.encrypt(aesnonce, m, None)
+    if _content_length == None:
+        _content_length = len(m)
+    if send_headers:
+        content_length = utils.int_to_bytes(_content_length)
+        content_length = bytes([len(content_length)]) + content_length
+    else:
+        content_length = b''
+    writer.write(start_byte + content_length + m)
+    await writer.drain()
+
+async def readmsg(reader: asyncio.StreamReader, aesgcm: AESGCM = None, aesnonce: bytes = None, start_byte: bytes = _MSG_START_BYTE) -> bytes:
+    '''
+    Receives a message.
+    
+    :param reader: The reader
+    :type reader: asyncio.StreamReader
+    :param aesgcm: AESGCM
+    :type aesgcm: AESGCM
+    :param aesnonce: The nonce
+    :type aesnonce: bytes
+    :param start_byte: The start byte
+    :type start_byte: bytes
+
+    :raises MessageFormatError: If the message format is invalid.
+
+    :return: The received message
+    :rtype: bytes
+    '''
+    if await reader.readexactly(1) != start_byte:
+        raise MessageFormatError('invalid message format')
+    content_length_length = await reader.readexactly(1)
+    content_length = await reader.readexactly(int.from_bytes(content_length_length))
+    m = await reader.readexactly(int.from_bytes(content_length))
+    if aesgcm:
+        return aesgcm.decrypt(aesnonce, m, None)
+    return m
+
+def pack_fields(*fields: bytes) -> bytes:
+    '''
+    Packs the fields into a compact bytestring.
+    
+    :param fields: The fields
+    :type fields: bytes
+
+    :return: The result
+    :rtype: bytes
+    '''
+    result = b''
+    for field in fields:
+        field_length = utils.int_to_bytes(len(field))
+        field_length_length = utils.int_to_bytes(len(field_length))
+        result += field_length_length + field_length + field
+    return result
+
+def unpack_fields(packed: bytes) -> Sequence[bytes]:
+    '''
+    Unpacks the field from a bytestring.
+    
+    :param packed: The packed fields
+    :type packed: bytes
+
+    :return: The unpacked fields
+    :rtype: Sequence[bytes]
+    '''
+    packed = []
+    buffer = io.BytesIO(packed)
+    while buffer.tell() < len(packed):
+        try:
+            field_length_length = int.from_bytes(buffer.read(1))
+            field_length = int.from_bytes(buffer.read(field_length_length))
+            field = buffer.read(field_length)
+            packed += (field,)
+        except:
+            pass
+    return packed