autobahn.websocket.compress_base

Classes

PerMessageCompress	Base class for WebSocket compression negotiated parameters.
PerMessageCompressOffer	Base class for WebSocket compression parameter client offers.
PerMessageCompressOfferAccept	Base class for WebSocket compression parameter client offer accepts by the server.
PerMessageCompressResponse	Base class for WebSocket compression parameter server responses.
PerMessageCompressResponseAccept	Base class for WebSocket compression parameter server response accepts by client.

Module Contents

class PerMessageCompress

Base class for WebSocket compression negotiated parameters.

Concrete subclasses (one per permessage-compress extension) implement the decompression interface used by the WebSocket protocol:

• start_decompress_message(self)

• decompress_message_data(self, data, max_output_len=None)

• end_decompress_message(self)

Bounded-decompression contract for decompress_message_data: when max_output_len is not None, the call returns at most max_output_len octets of decompressed output and raises autobahn.exception.PayloadExceededError if the input would produce more - it never silently truncates. max_output_len=None (the default) leaves decompression unbounded. Every backend stops decompressing near the budget, instead of inflating a whole frame first: deflate and bzip2 at exactly one octet over it, brotli at its library’s output buffer granularity, and snappy within one framing chunk (at most 64 KiB).

Input that cannot be decompressed (corrupt, truncated, or not the extension’s format) raises autobahn.exception.PayloadCorruptError from decompress_message_data or end_decompress_message, never the library’s own exception.

class PerMessageCompressOffer

Base class for WebSocket compression parameter client offers.

class PerMessageCompressOfferAccept

Base class for WebSocket compression parameter client offer accepts by the server.

class PerMessageCompressResponse

Base class for WebSocket compression parameter server responses.

class PerMessageCompressResponseAccept

Base class for WebSocket compression parameter server response accepts by client.