ugrpc::server::MiddlewareBase Class Reference

#include <userver/ugrpc/server/middlewares/base.hpp>

Detailed Description

Base class for server gRPC middleware.

Examples

samples/grpc_middleware_service/src/middlewares/server/auth.hpp, and samples/grpc_middleware_service/src/middlewares/server/meta_filter.hpp.

Definition at line 98 of file base.hpp.

Inheritance diagram for ugrpc::server::MiddlewareBase:

Public Member Functions
	MiddlewareBase (const MiddlewareBase &)=delete
MiddlewareBase &	operator= (const MiddlewareBase &)=delete
MiddlewareBase &	operator= (MiddlewareBase &&)=delete
virtual void	OnCallStart (MiddlewareCallContext &context) const
	This hook is invoked once per Call (RPC), after the message metadata is received, but before the handler function is called.
virtual void	PostRecvMessage (MiddlewareCallContext &context, google::protobuf::Message &request) const
	The function is invoked after each received message.
virtual void	PreSendMessage (MiddlewareCallContext &context, google::protobuf::Message &response) const
	The function is invoked before each sended message.
virtual void	OnCallFinish (MiddlewareCallContext &context, const grpc::Status &status) const
	This hook is invoked once per Call (RPC), after the handler function returns, but before the message is sent to the upstream client.

Member Function Documentation

OnCallFinish()

virtual void ugrpc::server::MiddlewareBase::OnCallFinish ( MiddlewareCallContext & context, const grpc::Status & status ) const

virtual

This hook is invoked once per Call (RPC), after the handler function returns, but before the message is sent to the upstream client.

All OnCallStart invoked in the reverse order relatively OnCallFinish. You can change grpc status and it will apply for a rpc call.

Warning

If Handler (grpc method) returns !ok status, OnCallFinish won't be called.

Reimplemented in ugrpc::server::middlewares::deadline_propagation::Middleware.

OnCallStart()

virtual void ugrpc::server::MiddlewareBase::OnCallStart ( MiddlewareCallContext & context ) const

virtual

This hook is invoked once per Call (RPC), after the message metadata is received, but before the handler function is called.

If all OnCallStart succeeded => OnCallFinish will invoked after a success method call.

Reimplemented in ugrpc::server::middlewares::baggage::Middleware, and ugrpc::server::middlewares::deadline_propagation::Middleware.

PostRecvMessage()

virtual void ugrpc::server::MiddlewareBase::PostRecvMessage ( MiddlewareCallContext & context, google::protobuf::Message & request ) const

virtual

The function is invoked after each received message.

PostRecvMessage is called:

• unary: exactly once per Call (RPC)
• stream: 0, 1 or more times

Reimplemented in grpc_protovalidate::server::Middleware.

PreSendMessage()

virtual void ugrpc::server::MiddlewareBase::PreSendMessage ( MiddlewareCallContext & context, google::protobuf::Message & response ) const

virtual

The function is invoked before each sended message.

PreSendMessage is called:

• unary: 0 or 1 per Call (RPC), depending on whether the RPC returns a response or a failed status
• stream: once per response message, that is, 0, 1, more times per Call (RPC).

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

• userver/ugrpc/server/middlewares/base.hpp