58 lines
1.8 KiB
Go
58 lines
1.8 KiB
Go
// Copyright 2016 Michal Witkowski. All Rights Reserved.
|
|
// See LICENSE for licensing terms.
|
|
|
|
package grpc_validator
|
|
|
|
import (
|
|
"golang.org/x/net/context"
|
|
"google.golang.org/grpc"
|
|
"google.golang.org/grpc/codes"
|
|
)
|
|
|
|
type validator interface {
|
|
Validate() error
|
|
}
|
|
|
|
// UnaryServerInterceptor returns a new unary server interceptor that validates incoming messages.
|
|
//
|
|
// Invalid messages will be rejected with `InvalidArgument` before reaching any userspace handlers.
|
|
func UnaryServerInterceptor() grpc.UnaryServerInterceptor {
|
|
return func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
|
|
if v, ok := req.(validator); ok {
|
|
if err := v.Validate(); err != nil {
|
|
return nil, grpc.Errorf(codes.InvalidArgument, err.Error())
|
|
}
|
|
}
|
|
return handler(ctx, req)
|
|
}
|
|
}
|
|
|
|
// StreamServerInterceptor returns a new streaming server interceptor that validates incoming messages.
|
|
//
|
|
// The stage at which invalid messages will be rejected with `InvalidArgument` varies based on the
|
|
// type of the RPC. For `ServerStream` (1:m) requests, it will happen before reaching any userspace
|
|
// handlers. For `ClientStream` (n:1) or `BidiStream` (n:m) RPCs, the messages will be rejected on
|
|
// calls to `stream.Recv()`.
|
|
func StreamServerInterceptor() grpc.StreamServerInterceptor {
|
|
return func(srv interface{}, stream grpc.ServerStream, info *grpc.StreamServerInfo, handler grpc.StreamHandler) error {
|
|
wrapper := &recvWrapper{stream}
|
|
return handler(srv, wrapper)
|
|
}
|
|
}
|
|
|
|
type recvWrapper struct {
|
|
grpc.ServerStream
|
|
}
|
|
|
|
func (s *recvWrapper) RecvMsg(m interface{}) error {
|
|
if err := s.ServerStream.RecvMsg(m); err != nil {
|
|
return err
|
|
}
|
|
if v, ok := m.(validator); ok {
|
|
if err := v.Validate(); err != nil {
|
|
return grpc.Errorf(codes.InvalidArgument, err.Error())
|
|
}
|
|
}
|
|
return nil
|
|
}
|