File size: 2,903 Bytes
9c6594c |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 |
from __future__ import annotations
from collections.abc import Sequence
from ..frames import Frame
from ..typing import ExtensionName, ExtensionParameter
__all__ = ["Extension", "ClientExtensionFactory", "ServerExtensionFactory"]
class Extension:
"""
Base class for extensions.
"""
name: ExtensionName
"""Extension identifier."""
def decode(self, frame: Frame, *, max_size: int | None = None) -> Frame:
"""
Decode an incoming frame.
Args:
frame: Incoming frame.
max_size: Maximum payload size in bytes.
Returns:
Decoded frame.
Raises:
PayloadTooBig: If decoding the payload exceeds ``max_size``.
"""
raise NotImplementedError
def encode(self, frame: Frame) -> Frame:
"""
Encode an outgoing frame.
Args:
frame: Outgoing frame.
Returns:
Encoded frame.
"""
raise NotImplementedError
class ClientExtensionFactory:
"""
Base class for client-side extension factories.
"""
name: ExtensionName
"""Extension identifier."""
def get_request_params(self) -> Sequence[ExtensionParameter]:
"""
Build parameters to send to the server for this extension.
Returns:
Parameters to send to the server.
"""
raise NotImplementedError
def process_response_params(
self,
params: Sequence[ExtensionParameter],
accepted_extensions: Sequence[Extension],
) -> Extension:
"""
Process parameters received from the server.
Args:
params: Parameters received from the server for this extension.
accepted_extensions: List of previously accepted extensions.
Returns:
An extension instance.
Raises:
NegotiationError: If parameters aren't acceptable.
"""
raise NotImplementedError
class ServerExtensionFactory:
"""
Base class for server-side extension factories.
"""
name: ExtensionName
"""Extension identifier."""
def process_request_params(
self,
params: Sequence[ExtensionParameter],
accepted_extensions: Sequence[Extension],
) -> tuple[list[ExtensionParameter], Extension]:
"""
Process parameters received from the client.
Args:
params: Parameters received from the client for this extension.
accepted_extensions: List of previously accepted extensions.
Returns:
To accept the offer, parameters to send to the client for this
extension and an extension instance.
Raises:
NegotiationError: To reject the offer, if parameters received from
the client aren't acceptable.
"""
raise NotImplementedError
|