cubefs

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/*
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 * Copyright 2019 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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// Package balancerload defines APIs to parse server loads in trailers. The
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// parsed loads are sent to balancers in DoneInfo.
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package balancerload
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import (
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	"google.golang.org/grpc/metadata"
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)
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// Parser converts loads from metadata into a concrete type.
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type Parser interface {
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	// Parse parses loads from metadata.
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	Parse(md metadata.MD) interface{}
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}
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var parser Parser
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// SetParser sets the load parser.
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//
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// Not mutex-protected, should be called before any gRPC functions.
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func SetParser(lr Parser) {
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	parser = lr
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}
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// Parse calls parser.Read().
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func Parse(md metadata.MD) interface{} {
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	if parser == nil {
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		return nil
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	}
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	return parser.Parse(md)
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}
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