github.com/hxx258456/ccgo@v0.0.5-0.20230213014102-48b35f46f66f/go-grpc-middleware/tracing/opentracing/options.go (about)

     1  // Copyright 2017 Michal Witkowski. All Rights Reserved.
     2  // See LICENSE for licensing terms.
     3  
     4  package grpc_opentracing
     5  
     6  import (
     7  	"context"
     8  
     9  	"github.com/opentracing/opentracing-go"
    10  )
    11  
    12  var (
    13  	defaultOptions = &options{
    14  		filterOutFunc: nil,
    15  		tracer:        nil,
    16  	}
    17  )
    18  
    19  // FilterFunc allows users to provide a function that filters out certain methods from being traced.
    20  //
    21  // If it returns false, the given request will not be traced.
    22  type FilterFunc func(ctx context.Context, fullMethodName string) bool
    23  
    24  type options struct {
    25  	filterOutFunc FilterFunc
    26  	tracer        opentracing.Tracer
    27  }
    28  
    29  func evaluateOptions(opts []Option) *options {
    30  	optCopy := &options{}
    31  	*optCopy = *defaultOptions
    32  	for _, o := range opts {
    33  		o(optCopy)
    34  	}
    35  	if optCopy.tracer == nil {
    36  		optCopy.tracer = opentracing.GlobalTracer()
    37  	}
    38  	return optCopy
    39  }
    40  
    41  type Option func(*options)
    42  
    43  // WithFilterFunc customizes the function used for deciding whether a given call is traced or not.
    44  func WithFilterFunc(f FilterFunc) Option {
    45  	return func(o *options) {
    46  		o.filterOutFunc = f
    47  	}
    48  }
    49  
    50  // WithTracer sets a custom tracer to be used for this middleware, otherwise the opentracing.GlobalTracer is used.
    51  func WithTracer(tracer opentracing.Tracer) Option {
    52  	return func(o *options) {
    53  		o.tracer = tracer
    54  	}
    55  }