Girish Kumar | 46d7c3a | 2020-05-18 12:06:33 +0000 | [diff] [blame^] | 1 | // Copyright (c) 2017 Uber Technologies, Inc. |
| 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 | |
| 15 | package rpcmetrics |
| 16 | |
| 17 | import ( |
| 18 | "strconv" |
| 19 | "sync" |
| 20 | "time" |
| 21 | |
| 22 | "github.com/opentracing/opentracing-go" |
| 23 | "github.com/opentracing/opentracing-go/ext" |
| 24 | "github.com/uber/jaeger-lib/metrics" |
| 25 | |
| 26 | jaeger "github.com/uber/jaeger-client-go" |
| 27 | ) |
| 28 | |
| 29 | const defaultMaxNumberOfEndpoints = 200 |
| 30 | |
| 31 | // Observer is an observer that can emit RPC metrics. |
| 32 | type Observer struct { |
| 33 | metricsByEndpoint *MetricsByEndpoint |
| 34 | } |
| 35 | |
| 36 | // NewObserver creates a new observer that can emit RPC metrics. |
| 37 | func NewObserver(metricsFactory metrics.Factory, normalizer NameNormalizer) *Observer { |
| 38 | return &Observer{ |
| 39 | metricsByEndpoint: newMetricsByEndpoint( |
| 40 | metricsFactory, |
| 41 | normalizer, |
| 42 | defaultMaxNumberOfEndpoints, |
| 43 | ), |
| 44 | } |
| 45 | } |
| 46 | |
| 47 | // OnStartSpan creates a new Observer for the span. |
| 48 | func (o *Observer) OnStartSpan( |
| 49 | operationName string, |
| 50 | options opentracing.StartSpanOptions, |
| 51 | ) jaeger.SpanObserver { |
| 52 | return NewSpanObserver(o.metricsByEndpoint, operationName, options) |
| 53 | } |
| 54 | |
| 55 | // SpanKind identifies the span as inboud, outbound, or internal |
| 56 | type SpanKind int |
| 57 | |
| 58 | const ( |
| 59 | // Local span kind |
| 60 | Local SpanKind = iota |
| 61 | // Inbound span kind |
| 62 | Inbound |
| 63 | // Outbound span kind |
| 64 | Outbound |
| 65 | ) |
| 66 | |
| 67 | // SpanObserver collects RPC metrics |
| 68 | type SpanObserver struct { |
| 69 | metricsByEndpoint *MetricsByEndpoint |
| 70 | operationName string |
| 71 | startTime time.Time |
| 72 | mux sync.Mutex |
| 73 | kind SpanKind |
| 74 | httpStatusCode uint16 |
| 75 | err bool |
| 76 | } |
| 77 | |
| 78 | // NewSpanObserver creates a new SpanObserver that can emit RPC metrics. |
| 79 | func NewSpanObserver( |
| 80 | metricsByEndpoint *MetricsByEndpoint, |
| 81 | operationName string, |
| 82 | options opentracing.StartSpanOptions, |
| 83 | ) *SpanObserver { |
| 84 | so := &SpanObserver{ |
| 85 | metricsByEndpoint: metricsByEndpoint, |
| 86 | operationName: operationName, |
| 87 | startTime: options.StartTime, |
| 88 | } |
| 89 | for k, v := range options.Tags { |
| 90 | so.handleTagInLock(k, v) |
| 91 | } |
| 92 | return so |
| 93 | } |
| 94 | |
| 95 | // handleTags watches for special tags |
| 96 | // - SpanKind |
| 97 | // - HttpStatusCode |
| 98 | // - Error |
| 99 | func (so *SpanObserver) handleTagInLock(key string, value interface{}) { |
| 100 | if key == string(ext.SpanKind) { |
| 101 | if v, ok := value.(ext.SpanKindEnum); ok { |
| 102 | value = string(v) |
| 103 | } |
| 104 | if v, ok := value.(string); ok { |
| 105 | if v == string(ext.SpanKindRPCClientEnum) { |
| 106 | so.kind = Outbound |
| 107 | } else if v == string(ext.SpanKindRPCServerEnum) { |
| 108 | so.kind = Inbound |
| 109 | } |
| 110 | } |
| 111 | return |
| 112 | } |
| 113 | if key == string(ext.HTTPStatusCode) { |
| 114 | if v, ok := value.(uint16); ok { |
| 115 | so.httpStatusCode = v |
| 116 | } else if v, ok := value.(int); ok { |
| 117 | so.httpStatusCode = uint16(v) |
| 118 | } else if v, ok := value.(string); ok { |
| 119 | if vv, err := strconv.Atoi(v); err == nil { |
| 120 | so.httpStatusCode = uint16(vv) |
| 121 | } |
| 122 | } |
| 123 | return |
| 124 | } |
| 125 | if key == string(ext.Error) { |
| 126 | if v, ok := value.(bool); ok { |
| 127 | so.err = v |
| 128 | } else if v, ok := value.(string); ok { |
| 129 | if vv, err := strconv.ParseBool(v); err == nil { |
| 130 | so.err = vv |
| 131 | } |
| 132 | } |
| 133 | return |
| 134 | } |
| 135 | } |
| 136 | |
| 137 | // OnFinish emits the RPC metrics. It only has an effect when operation name |
| 138 | // is not blank, and the span kind is an RPC server. |
| 139 | func (so *SpanObserver) OnFinish(options opentracing.FinishOptions) { |
| 140 | so.mux.Lock() |
| 141 | defer so.mux.Unlock() |
| 142 | |
| 143 | if so.operationName == "" || so.kind != Inbound { |
| 144 | return |
| 145 | } |
| 146 | |
| 147 | mets := so.metricsByEndpoint.get(so.operationName) |
| 148 | latency := options.FinishTime.Sub(so.startTime) |
| 149 | if so.err { |
| 150 | mets.RequestCountFailures.Inc(1) |
| 151 | mets.RequestLatencyFailures.Record(latency) |
| 152 | } else { |
| 153 | mets.RequestCountSuccess.Inc(1) |
| 154 | mets.RequestLatencySuccess.Record(latency) |
| 155 | } |
| 156 | mets.recordHTTPStatusCode(so.httpStatusCode) |
| 157 | } |
| 158 | |
| 159 | // OnSetOperationName records new operation name. |
| 160 | func (so *SpanObserver) OnSetOperationName(operationName string) { |
| 161 | so.mux.Lock() |
| 162 | so.operationName = operationName |
| 163 | so.mux.Unlock() |
| 164 | } |
| 165 | |
| 166 | // OnSetTag implements SpanObserver |
| 167 | func (so *SpanObserver) OnSetTag(key string, value interface{}) { |
| 168 | so.mux.Lock() |
| 169 | so.handleTagInLock(key, value) |
| 170 | so.mux.Unlock() |
| 171 | } |