cubefs

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/*
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 *
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 * Copyright 2016 gRPC authors.
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 *
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 * Licensed under the Apache License, Version 2.0 (the "License");
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 * you may not use this file except in compliance with the License.
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 * You may obtain a copy of the License at
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 *
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 *     http://www.apache.org/licenses/LICENSE-2.0
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 *
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 * Unless required by applicable law or agreed to in writing, software
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 * distributed under the License is distributed on an "AS IS" BASIS,
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 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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 * See the License for the specific language governing permissions and
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 * limitations under the License.
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 *
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 */
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// Package tap defines the function handles which are executed on the transport
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// layer of gRPC-Go and related information.
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//
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// Experimental
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//
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// Notice: This API is EXPERIMENTAL and may be changed or removed in a
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// later release.
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package tap
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import (
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	"context"
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)
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// Info defines the relevant information needed by the handles.
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type Info struct {
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	// FullMethodName is the string of grpc method (in the format of
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	// /package.service/method).
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	FullMethodName string
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	// TODO: More to be added.
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}
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// ServerInHandle defines the function which runs before a new stream is created
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// on the server side. If it returns a non-nil error, the stream will not be
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// created and a RST_STREAM will be sent back to the client with REFUSED_STREAM.
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// The client will receive an RPC error "code = Unavailable, desc = stream
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// terminated by RST_STREAM with error code: REFUSED_STREAM".
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//
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// It's intended to be used in situations where you don't want to waste the
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// resources to accept the new stream (e.g. rate-limiting). And the content of
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// the error will be ignored and won't be sent back to the client. For other
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// general usages, please use interceptors.
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//
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// Note that it is executed in the per-connection I/O goroutine(s) instead of
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// per-RPC goroutine. Therefore, users should NOT have any
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// blocking/time-consuming work in this handle. Otherwise all the RPCs would
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// slow down. Also, for the same reason, this handle won't be called
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// concurrently by gRPC.
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type ServerInHandle func(ctx context.Context, info *Info) (context.Context, error)
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