github.com/hxx258456/ccgo@v0.0.5-0.20230213014102-48b35f46f66f/grpc/internal/balancerload/load.go (about)

     1  /*
     2   * Copyright 2019 gRPC authors.
     3   *
     4   * Licensed under the Apache License, Version 2.0 (the "License");
     5   * you may not use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   *
     8   *     http://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  
    17  // Package balancerload defines APIs to parse server loads in trailers. The
    18  // parsed loads are sent to balancers in DoneInfo.
    19  package balancerload
    20  
    21  import (
    22  	"github.com/hxx258456/ccgo/grpc/metadata"
    23  )
    24  
    25  // Parser converts loads from metadata into a concrete type.
    26  type Parser interface {
    27  	// Parse parses loads from metadata.
    28  	Parse(md metadata.MD) interface{}
    29  }
    30  
    31  var parser Parser
    32  
    33  // SetParser sets the load parser.
    34  //
    35  // Not mutex-protected, should be called before any gRPC functions.
    36  func SetParser(lr Parser) {
    37  	parser = lr
    38  }
    39  
    40  // Parse calls parser.Read().
    41  func Parse(md metadata.MD) interface{} {
    42  	if parser == nil {
    43  		return nil
    44  	}
    45  	return parser.Parse(md)
    46  }