status-go/vendor/nhooyr.io/websocket/compress.go

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package websocket
// CompressionMode represents the modes available to the deflate extension.
// See https://tools.ietf.org/html/rfc7692
//
// A compatibility layer is implemented for the older deflate-frame extension used
// by safari. See https://tools.ietf.org/html/draft-tyoshino-hybi-websocket-perframe-deflate-06
// It will work the same in every way except that we cannot signal to the peer we
// want to use no context takeover on our side, we can only signal that they should.
// It is however currently disabled due to Safari bugs. See https://github.com/nhooyr/websocket/issues/218
type CompressionMode int
const (
// CompressionNoContextTakeover grabs a new flate.Reader and flate.Writer as needed
// for every message. This applies to both server and client side.
//
// This means less efficient compression as the sliding window from previous messages
// will not be used but the memory overhead will be lower if the connections
// are long lived and seldom used.
//
// The message will only be compressed if greater than 512 bytes.
CompressionNoContextTakeover CompressionMode = iota
// CompressionContextTakeover uses a flate.Reader and flate.Writer per connection.
// This enables reusing the sliding window from previous messages.
// As most WebSocket protocols are repetitive, this can be very efficient.
// It carries an overhead of 8 kB for every connection compared to CompressionNoContextTakeover.
//
// If the peer negotiates NoContextTakeover on the client or server side, it will be
// used instead as this is required by the RFC.
CompressionContextTakeover
// CompressionDisabled disables the deflate extension.
//
// Use this if you are using a predominantly binary protocol with very
// little duplication in between messages or CPU and memory are more
// important than bandwidth.
CompressionDisabled
)