caf::net::web_socket::handshake Class Reference

Wraps state and algorithms for the WebSocket client handshake as defined in RFC 6455. More...

#include <handshake.hpp>

Public Types
using	key_type = std::array<std::byte, 16>

Public Member Functions
	handshake (const handshake &)=default
	handshake (handshake &&) noexcept=default
handshake &	operator= (const handshake &)=default
handshake &	operator= (handshake &&) noexcept=default
const auto &	key () const noexcept
	Returns the 16-byte key for the opening handshake.
void	key (key_type new_key) noexcept
	Sets the 16-byte key for the opening handshake.
bool	assign_key (std::string_view base64_key)
	Tries to assign a key from base64 input.
std::string	response_key () const
	Returns the key for the response message, i.e., what the server puts into the HTTP field Sec-WebSocket-Accept.
const auto &	fields () const noexcept
	Returns all configured header fields, except the key.
bool	has_valid_key () const noexcept
	Checks whether at least one bit in the key is one.
bool	has_mandatory_fields () const noexcept
	Checks whether all mandatory fields were provided by the user.
void	randomize_key ()
	Fills the key with pseudo-random numbers generated by std::minstd_rand with a seed chosen from std::random_device.
void	randomize_key (unsigned seed)
	Fills the key with pseudo-random numbers generated by std::minstd_rand, initialized with seed.
void	endpoint (std::string value)
	Sets a value for the mandatory WebSocket endpoint, i.e., the Request-URI component of the GET method according to RFC 2616.
bool	has_endpoint () const noexcept
	Checks whether the handshake has an endpoint defined.
void	host (std::string value)
	Sets a value for the mandatory Host field.
bool	has_host () const noexcept
	Checks whether the handshake has an host defined.
void	origin (std::string value)
	Sets a value for the optional Origin field.
void	protocols (std::string value)
	Sets a value for the optional Sec-WebSocket-Protocol field.
void	extensions (std::string value)
	Sets a value for the optional Sec-WebSocket-Extensions field.
void	write_http_1_request (byte_buffer &buf) const
	Writes the HTTP 1.1 request message to buf.
void	write_http_1_response (byte_buffer &buf) const
	Writes the HTTP 1.1 response message to buf.
void	write_response (http::lower_layer::server *down) const
	Writes the HTTP response message to down.
bool	is_valid_http_1_response (std::string_view http_response) const
	Checks whether the http_response contains a HTTP 1.1 response to the generated HTTP GET request.

Static Public Attributes
static constexpr uint32_t	max_http_size = 2048
	Maximum size for HTTP request and response messages.

Detailed Description

Wraps state and algorithms for the WebSocket client handshake as defined in RFC 6455.

Member Function Documentation

endpoint()

void caf::net::web_socket::handshake::endpoint

(

std::string

value

)

Sets a value for the mandatory WebSocket endpoint, i.e., the Request-URI component of the GET method according to RFC 2616.

Parameters

value

Identifies the endpoint that should handle the request.

extensions()

void caf::net::web_socket::handshake::extensions

(

std::string

value

)

Sets a value for the optional Sec-WebSocket-Extensions field.

Parameters

value

A comma-separated list of values indicating which extensions the client would like to speak, ordered by preference.

has_valid_key()

bool caf::net::web_socket::handshake::has_valid_key ( ) const

nodiscardnoexcept

Checks whether at least one bit in the key is one.

A default constructed header object fills the key with zeros.

host()

void caf::net::web_socket::handshake::host

(

std::string

value

)

Sets a value for the mandatory Host field.

Parameters

value

The Internet host and port number of the resource being requested, as obtained from the original URI given by the user or referring resource.

is_valid_http_1_response()

bool caf::net::web_socket::handshake::is_valid_http_1_response

(

std::string_view

http_response

)

const

Checks whether the http_response contains a HTTP 1.1 response to the generated HTTP GET request.

A valid response contains:

• HTTP status code 101 (Switching Protocols).
• An Upgrade field with the value websocket.
• A Connection field with the value Upgrade.
• A Sec-WebSocket-Accept field with the value response_key().

origin()

void caf::net::web_socket::handshake::origin

(

std::string

value

)

Sets a value for the optional Origin field.

Parameters

value

Indicates where the GET request originates from. Usually only sent by browser clients.

protocols()

void caf::net::web_socket::handshake::protocols

(

std::string

value

)

Sets a value for the optional Sec-WebSocket-Protocol field.

Parameters

value

A comma-separated list of values indicating which protocols the client would like to speak, ordered by preference.

write_http_1_request()

void caf::net::web_socket::handshake::write_http_1_request

(

byte_buffer &

buf

)

const

Writes the HTTP 1.1 request message to buf.

Precondition

has_mandatory_fields()

write_http_1_response()

void caf::net::web_socket::handshake::write_http_1_response

(

byte_buffer &

buf

)

const

Writes the HTTP 1.1 response message to buf.

Precondition

has_valid_key()

write_response()

void caf::net::web_socket::handshake::write_response

(

http::lower_layer::server *

down

)

const

Writes the HTTP response message to down.

Precondition

has_valid_key()

Member Data Documentation

max_http_size

uint32_t caf::net::web_socket::handshake::max_http_size = 2048

staticconstexpr

Maximum size for HTTP request and response messages.

A handshake should usually fit into 200-300 Bytes, so 2KB is more than enough.

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The documentation for this class was generated from the following files:

• libcaf_net/caf/net/web_socket/handshake.hpp
• libcaf_net/caf/net/web_socket/handshake.cpp