1// Copyright (c) 2018 The Jaeger Authors. 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); 4// you may not use this file except in compliance with the License. 5// You may obtain a copy of the License at 6// 7// http://www.apache.org/licenses/LICENSE-2.0 8// 9// Unless required by applicable law or agreed to in writing, software 10// distributed under the License is distributed on an "AS IS" BASIS, 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12// See the License for the specific language governing permissions and 13// limitations under the License. 14 15package remote 16 17import ( 18 "time" 19 20 "github.com/uber/jaeger-client-go" 21) 22 23const ( 24 defaultHostPort = "localhost:5778" 25 defaultRefreshInterval = time.Second * 5 26) 27 28// Option is a function that sets some option on the Throttler 29type Option func(options *options) 30 31// Options is a factory for all available options 32var Options options 33 34type options struct { 35 metrics *jaeger.Metrics 36 logger jaeger.Logger 37 hostPort string 38 refreshInterval time.Duration 39 synchronousInitialization bool 40} 41 42// Metrics creates an Option that initializes Metrics on the Throttler, which is used to emit statistics. 43func (options) Metrics(m *jaeger.Metrics) Option { 44 return func(o *options) { 45 o.metrics = m 46 } 47} 48 49// Logger creates an Option that sets the logger used by the Throttler. 50func (options) Logger(logger jaeger.Logger) Option { 51 return func(o *options) { 52 o.logger = logger 53 } 54} 55 56// HostPort creates an Option that sets the hostPort of the local agent that keeps track of credits. 57func (options) HostPort(hostPort string) Option { 58 return func(o *options) { 59 o.hostPort = hostPort 60 } 61} 62 63// RefreshInterval creates an Option that sets how often the Throttler will poll local agent for 64// credits. 65func (options) RefreshInterval(refreshInterval time.Duration) Option { 66 return func(o *options) { 67 o.refreshInterval = refreshInterval 68 } 69} 70 71// SynchronousInitialization creates an Option that determines whether the throttler should synchronously 72// fetch credits from the agent when an operation is seen for the first time. This should be set to true 73// if the client will be used by a short lived service that needs to ensure that credits are fetched upfront 74// such that sampling or throttling occurs. 75func (options) SynchronousInitialization(b bool) Option { 76 return func(o *options) { 77 o.synchronousInitialization = b 78 } 79} 80 81func applyOptions(o ...Option) options { 82 opts := options{} 83 for _, option := range o { 84 option(&opts) 85 } 86 if opts.metrics == nil { 87 opts.metrics = jaeger.NewNullMetrics() 88 } 89 if opts.logger == nil { 90 opts.logger = jaeger.NullLogger 91 } 92 if opts.hostPort == "" { 93 opts.hostPort = defaultHostPort 94 } 95 if opts.refreshInterval == 0 { 96 opts.refreshInterval = defaultRefreshInterval 97 } 98 return opts 99} 100