#include <userver/server/websocket/websocket_handler.hpp>

Detailed Description

Base class for WebSocket handler.

Static options:

Inherits all the options from server::handlers::HandlerBase and adds the following ones:

Name	Description	Default value
log-level	overrides log level for this handle	<no override>
status-codes-log-level	map of "status": log_level items to override span log level for specific status codes	{}
max-remote-payload	max remote payload size	65536
fragment-size	max output fragment size	65536

Example usage:

#include <userver/components/minimal_server_component_list.hpp>
#include <userver/server/websocket/websocket_handler.hpp>
#include <userver/utils/daemon_run.hpp>
 
namespace samples::websocket {
 
class WebsocketsHandler final : public server::websocket::WebsocketHandlerBase {
public:
    // `kName` is used as the component name in static config
    static constexpr std::string_view kName = "websocket-handler";
 
    // Component is valid after construction and is able to accept requests
    using WebsocketHandlerBase::WebsocketHandlerBase;
 
    void Handle(server::websocket::WebSocketConnection& chat, server::request::RequestContext&) const override {
        server::websocket::Message message;
        while (!engine::current_task::ShouldCancel()) {
            chat.Recv(message);               // throws on closed/dropped connection
            if (message.close_status) break;  // explicit close if any
            chat.Send(std::move(message));    // throws on closed/dropped connection
        }
        if (message.close_status) chat.Close(*message.close_status);
    }
};
 
}  // namespace samples::websocket

Examples: samples/websocket_service/websocket_service.cpp.

Definition at line 37 of file websocket_handler.hpp.

Inheritance diagram for server::websocket::WebsocketHandlerBase:

Public Member Functions
	WebsocketHandlerBase (const components::ComponentConfig &, const components::ComponentContext &)

virtual void	Handle (WebSocketConnection &websocket, server::request::RequestContext &) const =0
	Websocket handler code belongs here.

virtual bool	HandleHandshake (const server::http::HttpRequest &, server::http::HttpResponse &, server::request::RequestContext &) const
	If any code is required for handshake validation, it goes here.

virtual void	HandleNonWebsocketRequest (const server::http::HttpRequest &request, server::request::RequestContext &context) const
	If request isn't a websocket request the function handles a request.

void	PrepareAndHandleRequest (http::HttpRequest &request, request::RequestContext &context) const override

void	ReportMalformedRequest (http::HttpRequest &request) const final

virtual const std::string &	HandlerName () const

const std::vector< http::HttpMethod > &	GetAllowedMethods () const

virtual logging::Level	GetLogLevelForResponseStatus (http::HttpStatus status) const

virtual FormattedErrorData	GetFormattedExternalErrorBody (const CustomHandlerException &exc) const

std::string	GetResponseDataForLoggingChecked (const http::HttpRequest &request, request::RequestContext &context, const std::string &response_data) const

void	HandleCustomHandlerException (const http::HttpRequest &request, const CustomHandlerException &ex) const

void	HandleUnknownException (const http::HttpRequest &request, const std::exception &ex) const

void	LogUnknownException (const std::exception &ex, std::optional< logging::Level > log_level_override={}) const
	Helper function to log an unknown exception.

const std::optional< logging::Level > &	GetLogLevel () const
	Returns the default log level for the handler.

bool	IsMonitor () const
	Returns whether this is a monitoring handler.

const HandlerConfig &	GetConfig () const
	Returns handler config.

ComponentHealth	GetComponentHealth () const override

void	OnLoadingCancelled () override

void	OnAllComponentsLoaded () override

void	OnAllComponentsAreStopping () override

Static Public Member Functions
static yaml_config::Schema	GetStaticConfigSchema ()

Protected Types
using	HandlerErrorCode = handlers::HandlerErrorCode

using	InternalMessage = handlers::InternalMessage

using	ExternalBody = handlers::ExternalBody

using	ClientError = handlers::ClientError

using	InternalServerError = handlers::InternalServerError

using	LoggableComponentBase = ComponentBase
	Legacy alias, use ComponentBase instead.

Protected Member Functions
void	ThrowUnsupportedHttpMethod (const http::HttpRequest &request) const

virtual std::string	HandleRequest (http::HttpRequest &request, request::RequestContext &context) const

virtual void	HandleStreamRequest (server::http::HttpRequest &, server::request::RequestContext &, server::http::ResponseBodyStream &) const

virtual bool	IsStreamed () const

virtual bool	IsMethodStatisticIncluded () const

virtual bool	NeedCheckAuth () const

virtual std::string	GetRequestBodyForLogging (const http::HttpRequest &request, request::RequestContext &context, const std::string &request_body) const
	Override it if you need a custom request body logging.

virtual std::string	GetResponseDataForLogging (const http::HttpRequest &request, request::RequestContext &context, const std::string &response_data) const
	Override it if you need a custom response data logging.

virtual void	ParseRequestData (const http::HttpRequest &, request::RequestContext &) const

virtual std::string	GetMetaType (const http::HttpRequest &) const

Member Typedef Documentation

◆ ClientError

using server::handlers::HandlerBase::ClientError = handlers::ClientError

protectedinherited

Definition at line 80 of file handler_base.hpp.

◆ ExternalBody

using server::handlers::HandlerBase::ExternalBody = handlers::ExternalBody

protectedinherited

Definition at line 78 of file handler_base.hpp.

◆ HandlerErrorCode

using server::handlers::HandlerBase::HandlerErrorCode = handlers::HandlerErrorCode

protectedinherited

Definition at line 76 of file handler_base.hpp.

◆ InternalMessage

using server::handlers::HandlerBase::InternalMessage = handlers::InternalMessage

protectedinherited

Definition at line 77 of file handler_base.hpp.

◆ InternalServerError

using server::handlers::HandlerBase::InternalServerError = handlers::InternalServerError

protectedinherited

Definition at line 81 of file handler_base.hpp.

◆ LoggableComponentBase

using components::ComponentBase::LoggableComponentBase = ComponentBase

protectedinherited

Legacy alias, use ComponentBase instead.

Definition at line 67 of file component_base.hpp.

Member Function Documentation

◆ GetComponentHealth()

ComponentHealth components::ComponentBase::GetComponentHealth ( ) const

inlineoverridevirtualinherited

Override this function to inform the world of the state of your component.

Warning: The function is called concurrently from multiple threads.

Reimplemented from components::RawComponentBase.

Reimplemented in server::handlers::Restart.

Definition at line 35 of file component_base.hpp.

◆ GetLogLevelForResponseStatus()

virtual logging::Level server::handlers::HttpHandlerBase::GetLogLevelForResponseStatus ( http::HttpStatus status ) const

virtualinherited

Override it if you need a custom logging level for messages about finish of request handling for some http statuses.

◆ GetRequestBodyForLogging()

virtual std::string server::handlers::HttpHandlerBase::GetRequestBodyForLogging	(	const http::HttpRequest &	request,
		request::RequestContext &	context,
		const std::string &	request_body ) const

protectedvirtualinherited

Override it if you need a custom request body logging.

Reimplemented in server::handlers::HttpHandlerFlatbufBase< InputType, ReturnType >.

◆ GetResponseDataForLogging()

virtual std::string server::handlers::HttpHandlerBase::GetResponseDataForLogging	(	const http::HttpRequest &	request,
		request::RequestContext &	context,
		const std::string &	response_data ) const

protectedvirtualinherited

Override it if you need a custom response data logging.

Reimplemented in server::handlers::HttpHandlerFlatbufBase< InputType, ReturnType >.

◆ HandleCustomHandlerException()

void server::handlers::HttpHandlerBase::HandleCustomHandlerException	(	const http::HttpRequest &	request,
		const CustomHandlerException &	ex ) const

inherited

Takes the exception and formats it into response, as specified by exception.

◆ HandleHandshake()

virtual bool server::websocket::WebsocketHandlerBase::HandleHandshake	(	const server::http::HttpRequest &	,
		server::http::HttpResponse &	,
		server::request::RequestContext &	) const

inlinevirtual

If any code is required for handshake validation, it goes here.

Definition at line 47 of file websocket_handler.hpp.

◆ HandleNonWebsocketRequest()

virtual void server::websocket::WebsocketHandlerBase::HandleNonWebsocketRequest	(	const server::http::HttpRequest &	request,
		server::request::RequestContext &	context ) const

inlinevirtual

If request isn't a websocket request the function handles a request.

Definition at line 60 of file websocket_handler.hpp.

◆ HandleRequest()

virtual std::string server::handlers::HttpHandlerBase::HandleRequest	(	http::HttpRequest &	request,
		request::RequestContext &	context ) const

protectedvirtualinherited

The core method for HTTP request handling. request arg contains HTTP headers, full body, etc. The method should return response body.

Note: It is used only if IsStreamed() returned false.

Examples: samples/http_caching/http_caching.cpp.

◆ HandleStreamRequest()

virtual void server::handlers::HttpHandlerBase::HandleStreamRequest	(	server::http::HttpRequest &	,
		server::request::RequestContext &	,
		server::http::ResponseBodyStream &	) const

protectedvirtualinherited

The core method for HTTP request handling. request arg contains HTTP headers, full body, etc. The response body is passed in parts to ResponseBodyStream. Stream transmission is useful when: 1) The body size is unknown beforehand. 2) The client may take advantage of early body transmission (e.g. a Web Browser may start rendering the HTML page or downloading dependant resources). 3) The body size is huge and we want to have only a part of it in memory.

Note: It is used only if IsStreamed() returned true.

◆ HandleUnknownException()

void server::handlers::HttpHandlerBase::HandleUnknownException	(	const http::HttpRequest &	request,
		const std::exception &	ex ) const

inherited

Takes the exception and formats it into response as an internal server error.

◆ IsMethodStatisticIncluded()

virtual bool server::handlers::HttpHandlerBase::IsMethodStatisticIncluded ( ) const

inlineprotectedvirtualinherited

Override it to show per HTTP-method statistics besides statistics for all methods

Definition at line 156 of file http_handler_base.hpp.

◆ IsMonitor()

bool server::handlers::HandlerBase::IsMonitor ( ) const

inlineinherited

Returns whether this is a monitoring handler.

Definition at line 67 of file handler_base.hpp.

◆ IsStreamed()

virtual bool server::handlers::HttpHandlerBase::IsStreamed ( ) const

inlineprotectedvirtualinherited

If IsStreamed() returns true, call HandleStreamRequest() for request handling, HandleRequest() is not called. If it returns false, HandleRequest() is called instead, and HandleStreamRequest() is not called.

Note: The default implementation returns the cached value of "response-body-streamed" value from static config.

Definition at line 152 of file http_handler_base.hpp.

◆ NeedCheckAuth()

virtual bool server::handlers::HttpHandlerBase::NeedCheckAuth ( ) const

inlineprotectedvirtualinherited

Override it if you want to disable auth checks in handler by some condition

Definition at line 160 of file http_handler_base.hpp.

◆ OnAllComponentsAreStopping()

void components::ComponentBase::OnAllComponentsAreStopping ( )

inlineoverridevirtualinherited

Component may use this function to stop doing work before the stop of the components that depend on it.

Base components may override it and make final to do some work before the derived object constructor is called. Don't use it otherwise.

Reimplemented from components::RawComponentBase.

Reimplemented in urabbitmq::ConsumerComponentBase, and components::Server.

Definition at line 58 of file component_base.hpp.

◆ OnAllComponentsLoaded()

void components::ComponentBase::OnAllComponentsLoaded ( )

inlineoverridevirtualinherited

Component may use this function to finalize registration of other components that depend on it (for example, handler components register in server component, and the latter uses OnAllComponentsLoaded() to start processing requests).

Base components may override it and make final to do some work after the derived object constructor is called. Don't use it otherwise.

Reimplemented from components::RawComponentBase.

Reimplemented in urabbitmq::ConsumerComponentBase, components::Server, and server::handlers::Ping.

Definition at line 51 of file component_base.hpp.

◆ OnLoadingCancelled()

void components::ComponentBase::OnLoadingCancelled ( )

inlineoverridevirtualinherited

Called once if the creation of any other component failed. If the current component expects some other component to take any action with the current component, this call is a signal that such action may never happen due to components loading was cancelled. Application components might not want to override it.

Reimplemented from components::RawComponentBase.

Definition at line 42 of file component_base.hpp.

◆ ParseRequestData()

virtual void server::handlers::HttpHandlerBase::ParseRequestData	(	const http::HttpRequest &	,
		request::RequestContext &	) const

inlineprotectedvirtualinherited

For internal use. You don't need to override it. This method is overridden in format-specific base handlers.

Reimplemented in server::handlers::HttpHandlerFlatbufBase< InputType, ReturnType >, and server::handlers::HttpHandlerJsonBase.

Definition at line 178 of file http_handler_base.hpp.

◆ PrepareAndHandleRequest()

void server::handlers::HttpHandlerBase::PrepareAndHandleRequest	(	http::HttpRequest &	request,
		request::RequestContext &	context ) const

overridevirtualinherited

Parses request, executes processing routines, and fills response accordingly. Does not throw.

Implements server::handlers::HandlerBase.

◆ ReportMalformedRequest()

void server::handlers::HttpHandlerBase::ReportMalformedRequest ( http::HttpRequest & ) const

finalvirtualinherited

Produces response to a request unrecognized by the protocol based on provided generic response. Does not throw.

Reimplemented from server::handlers::HandlerBase.

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

userver/server/websocket/websocket_handler.hpp

Detailed Description

Static options:

Example usage:

Public Member Functions

Static Public Member Functions

Protected Types

Protected Member Functions

Member Typedef Documentation

◆ ClientError

◆ ExternalBody

◆ HandlerErrorCode

◆ InternalMessage

◆ InternalServerError

◆ LoggableComponentBase

Member Function Documentation

◆ GetComponentHealth()

◆ GetLogLevelForResponseStatus()

◆ GetRequestBodyForLogging()

◆ GetResponseDataForLogging()

◆ HandleCustomHandlerException()

◆ HandleHandshake()

◆ HandleNonWebsocketRequest()

◆ HandleRequest()

◆ HandleStreamRequest()

◆ HandleUnknownException()

◆ IsMethodStatisticIncluded()

◆ IsMonitor()

◆ IsStreamed()

◆ NeedCheckAuth()

◆ OnAllComponentsAreStopping()

◆ OnAllComponentsLoaded()

◆ OnLoadingCancelled()

◆ ParseRequestData()

◆ PrepareAndHandleRequest()

◆ ReportMalformedRequest()