| 1 | // Copyright 2019 The Go Authors. All rights reserved. |
|---|---|
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| 5 | // Package ocagent adds the ability to export all telemetry to an ocagent. |
| 6 | // This keeps the compile time dependencies to zero and allows the agent to |
| 7 | // have the exporters needed for telemetry aggregation and viewing systems. |
| 8 | package ocagent |
| 9 | |
| 10 | import ( |
| 11 | "bytes" |
| 12 | "context" |
| 13 | "encoding/json" |
| 14 | "fmt" |
| 15 | "net/http" |
| 16 | "os" |
| 17 | "path/filepath" |
| 18 | "sync" |
| 19 | "time" |
| 20 | |
| 21 | "golang.org/x/tools/internal/event" |
| 22 | "golang.org/x/tools/internal/event/core" |
| 23 | "golang.org/x/tools/internal/event/export" |
| 24 | "golang.org/x/tools/internal/event/export/metric" |
| 25 | "golang.org/x/tools/internal/event/export/ocagent/wire" |
| 26 | "golang.org/x/tools/internal/event/keys" |
| 27 | "golang.org/x/tools/internal/event/label" |
| 28 | ) |
| 29 | |
| 30 | type Config struct { |
| 31 | Start time.Time |
| 32 | Host string |
| 33 | Process uint32 |
| 34 | Client *http.Client |
| 35 | Service string |
| 36 | Address string |
| 37 | Rate time.Duration |
| 38 | } |
| 39 | |
| 40 | var ( |
| 41 | connectMu sync.Mutex |
| 42 | exporters = make(map[Config]*Exporter) |
| 43 | ) |
| 44 | |
| 45 | // Discover finds the local agent to export to, it will return nil if there |
| 46 | // is not one running. |
| 47 | // TODO: Actually implement a discovery protocol rather than a hard coded address |
| 48 | func Discover() *Config { |
| 49 | return &Config{ |
| 50 | Address: "http://localhost:55678", |
| 51 | } |
| 52 | } |
| 53 | |
| 54 | type Exporter struct { |
| 55 | mu sync.Mutex |
| 56 | config Config |
| 57 | spans []*export.Span |
| 58 | metrics []metric.Data |
| 59 | } |
| 60 | |
| 61 | // Connect creates a process specific exporter with the specified |
| 62 | // serviceName and the address of the ocagent to which it will upload |
| 63 | // its telemetry. |
| 64 | func Connect(config *Config) *Exporter { |
| 65 | if config == nil || config.Address == "off" { |
| 66 | return nil |
| 67 | } |
| 68 | resolved := *config |
| 69 | if resolved.Host == "" { |
| 70 | hostname, _ := os.Hostname() |
| 71 | resolved.Host = hostname |
| 72 | } |
| 73 | if resolved.Process == 0 { |
| 74 | resolved.Process = uint32(os.Getpid()) |
| 75 | } |
| 76 | if resolved.Client == nil { |
| 77 | resolved.Client = http.DefaultClient |
| 78 | } |
| 79 | if resolved.Service == "" { |
| 80 | resolved.Service = filepath.Base(os.Args[0]) |
| 81 | } |
| 82 | if resolved.Rate == 0 { |
| 83 | resolved.Rate = 2 * time.Second |
| 84 | } |
| 85 | |
| 86 | connectMu.Lock() |
| 87 | defer connectMu.Unlock() |
| 88 | if exporter, found := exporters[resolved]; found { |
| 89 | return exporter |
| 90 | } |
| 91 | exporter := &Exporter{config: resolved} |
| 92 | exporters[resolved] = exporter |
| 93 | if exporter.config.Start.IsZero() { |
| 94 | exporter.config.Start = time.Now() |
| 95 | } |
| 96 | go func() { |
| 97 | for range time.Tick(exporter.config.Rate) { |
| 98 | exporter.Flush() |
| 99 | } |
| 100 | }() |
| 101 | return exporter |
| 102 | } |
| 103 | |
| 104 | func (e *Exporter) ProcessEvent(ctx context.Context, ev core.Event, lm label.Map) context.Context { |
| 105 | switch { |
| 106 | case event.IsEnd(ev): |
| 107 | e.mu.Lock() |
| 108 | defer e.mu.Unlock() |
| 109 | span := export.GetSpan(ctx) |
| 110 | if span != nil { |
| 111 | e.spans = append(e.spans, span) |
| 112 | } |
| 113 | case event.IsMetric(ev): |
| 114 | e.mu.Lock() |
| 115 | defer e.mu.Unlock() |
| 116 | data := metric.Entries.Get(lm).([]metric.Data) |
| 117 | e.metrics = append(e.metrics, data...) |
| 118 | } |
| 119 | return ctx |
| 120 | } |
| 121 | |
| 122 | func (e *Exporter) Flush() { |
| 123 | e.mu.Lock() |
| 124 | defer e.mu.Unlock() |
| 125 | spans := make([]*wire.Span, len(e.spans)) |
| 126 | for i, s := range e.spans { |
| 127 | spans[i] = convertSpan(s) |
| 128 | } |
| 129 | e.spans = nil |
| 130 | metrics := make([]*wire.Metric, len(e.metrics)) |
| 131 | for i, m := range e.metrics { |
| 132 | metrics[i] = convertMetric(m, e.config.Start) |
| 133 | } |
| 134 | e.metrics = nil |
| 135 | |
| 136 | if len(spans) > 0 { |
| 137 | e.send("/v1/trace", &wire.ExportTraceServiceRequest{ |
| 138 | Node: e.config.buildNode(), |
| 139 | Spans: spans, |
| 140 | //TODO: Resource? |
| 141 | }) |
| 142 | } |
| 143 | if len(metrics) > 0 { |
| 144 | e.send("/v1/metrics", &wire.ExportMetricsServiceRequest{ |
| 145 | Node: e.config.buildNode(), |
| 146 | Metrics: metrics, |
| 147 | //TODO: Resource? |
| 148 | }) |
| 149 | } |
| 150 | } |
| 151 | |
| 152 | func (cfg *Config) buildNode() *wire.Node { |
| 153 | return &wire.Node{ |
| 154 | Identifier: &wire.ProcessIdentifier{ |
| 155 | HostName: cfg.Host, |
| 156 | Pid: cfg.Process, |
| 157 | StartTimestamp: convertTimestamp(cfg.Start), |
| 158 | }, |
| 159 | LibraryInfo: &wire.LibraryInfo{ |
| 160 | Language: wire.LanguageGo, |
| 161 | ExporterVersion: "0.0.1", |
| 162 | CoreLibraryVersion: "x/tools", |
| 163 | }, |
| 164 | ServiceInfo: &wire.ServiceInfo{ |
| 165 | Name: cfg.Service, |
| 166 | }, |
| 167 | } |
| 168 | } |
| 169 | |
| 170 | func (e *Exporter) send(endpoint string, message interface{}) { |
| 171 | blob, err := json.Marshal(message) |
| 172 | if err != nil { |
| 173 | errorInExport("ocagent failed to marshal message for %v: %v", endpoint, err) |
| 174 | return |
| 175 | } |
| 176 | uri := e.config.Address + endpoint |
| 177 | req, err := http.NewRequest("POST", uri, bytes.NewReader(blob)) |
| 178 | if err != nil { |
| 179 | errorInExport("ocagent failed to build request for %v: %v", uri, err) |
| 180 | return |
| 181 | } |
| 182 | req.Header.Set("Content-Type", "application/json") |
| 183 | res, err := e.config.Client.Do(req) |
| 184 | if err != nil { |
| 185 | errorInExport("ocagent failed to send message: %v \n", err) |
| 186 | return |
| 187 | } |
| 188 | if res.Body != nil { |
| 189 | res.Body.Close() |
| 190 | } |
| 191 | } |
| 192 | |
| 193 | func errorInExport(message string, args ...interface{}) { |
| 194 | // This function is useful when debugging the exporter, but in general we |
| 195 | // want to just drop any export |
| 196 | } |
| 197 | |
| 198 | func convertTimestamp(t time.Time) wire.Timestamp { |
| 199 | return t.Format(time.RFC3339Nano) |
| 200 | } |
| 201 | |
| 202 | func toTruncatableString(s string) *wire.TruncatableString { |
| 203 | if s == "" { |
| 204 | return nil |
| 205 | } |
| 206 | return &wire.TruncatableString{Value: s} |
| 207 | } |
| 208 | |
| 209 | func convertSpan(span *export.Span) *wire.Span { |
| 210 | result := &wire.Span{ |
| 211 | TraceID: span.ID.TraceID[:], |
| 212 | SpanID: span.ID.SpanID[:], |
| 213 | TraceState: nil, //TODO? |
| 214 | ParentSpanID: span.ParentID[:], |
| 215 | Name: toTruncatableString(span.Name), |
| 216 | Kind: wire.UnspecifiedSpanKind, |
| 217 | StartTime: convertTimestamp(span.Start().At()), |
| 218 | EndTime: convertTimestamp(span.Finish().At()), |
| 219 | Attributes: convertAttributes(span.Start(), 1), |
| 220 | TimeEvents: convertEvents(span.Events()), |
| 221 | SameProcessAsParentSpan: true, |
| 222 | //TODO: StackTrace? |
| 223 | //TODO: Links? |
| 224 | //TODO: Status? |
| 225 | //TODO: Resource? |
| 226 | } |
| 227 | return result |
| 228 | } |
| 229 | |
| 230 | func convertMetric(data metric.Data, start time.Time) *wire.Metric { |
| 231 | descriptor := dataToMetricDescriptor(data) |
| 232 | timeseries := dataToTimeseries(data, start) |
| 233 | |
| 234 | if descriptor == nil && timeseries == nil { |
| 235 | return nil |
| 236 | } |
| 237 | |
| 238 | // TODO: handle Histogram metrics |
| 239 | return &wire.Metric{ |
| 240 | MetricDescriptor: descriptor, |
| 241 | Timeseries: timeseries, |
| 242 | // TODO: attach Resource? |
| 243 | } |
| 244 | } |
| 245 | |
| 246 | func skipToValidLabel(list label.List, index int) (int, label.Label) { |
| 247 | // skip to the first valid label |
| 248 | for ; list.Valid(index); index++ { |
| 249 | l := list.Label(index) |
| 250 | if !l.Valid() || l.Key() == keys.Label { |
| 251 | continue |
| 252 | } |
| 253 | return index, l |
| 254 | } |
| 255 | return -1, label.Label{} |
| 256 | } |
| 257 | |
| 258 | func convertAttributes(list label.List, index int) *wire.Attributes { |
| 259 | index, l := skipToValidLabel(list, index) |
| 260 | if !l.Valid() { |
| 261 | return nil |
| 262 | } |
| 263 | attributes := make(map[string]wire.Attribute) |
| 264 | for { |
| 265 | if l.Valid() { |
| 266 | attributes[l.Key().Name()] = convertAttribute(l) |
| 267 | } |
| 268 | index++ |
| 269 | if !list.Valid(index) { |
| 270 | return &wire.Attributes{AttributeMap: attributes} |
| 271 | } |
| 272 | l = list.Label(index) |
| 273 | } |
| 274 | } |
| 275 | |
| 276 | func convertAttribute(l label.Label) wire.Attribute { |
| 277 | switch key := l.Key().(type) { |
| 278 | case *keys.Int: |
| 279 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 280 | case *keys.Int8: |
| 281 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 282 | case *keys.Int16: |
| 283 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 284 | case *keys.Int32: |
| 285 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 286 | case *keys.Int64: |
| 287 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 288 | case *keys.UInt: |
| 289 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 290 | case *keys.UInt8: |
| 291 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 292 | case *keys.UInt16: |
| 293 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 294 | case *keys.UInt32: |
| 295 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 296 | case *keys.UInt64: |
| 297 | return wire.IntAttribute{IntValue: int64(key.From(l))} |
| 298 | case *keys.Float32: |
| 299 | return wire.DoubleAttribute{DoubleValue: float64(key.From(l))} |
| 300 | case *keys.Float64: |
| 301 | return wire.DoubleAttribute{DoubleValue: key.From(l)} |
| 302 | case *keys.Boolean: |
| 303 | return wire.BoolAttribute{BoolValue: key.From(l)} |
| 304 | case *keys.String: |
| 305 | return wire.StringAttribute{StringValue: toTruncatableString(key.From(l))} |
| 306 | case *keys.Error: |
| 307 | return wire.StringAttribute{StringValue: toTruncatableString(key.From(l).Error())} |
| 308 | case *keys.Value: |
| 309 | return wire.StringAttribute{StringValue: toTruncatableString(fmt.Sprint(key.From(l)))} |
| 310 | default: |
| 311 | return wire.StringAttribute{StringValue: toTruncatableString(fmt.Sprintf("%T", key))} |
| 312 | } |
| 313 | } |
| 314 | |
| 315 | func convertEvents(events []core.Event) *wire.TimeEvents { |
| 316 | //TODO: MessageEvents? |
| 317 | result := make([]wire.TimeEvent, len(events)) |
| 318 | for i, event := range events { |
| 319 | result[i] = convertEvent(event) |
| 320 | } |
| 321 | return &wire.TimeEvents{TimeEvent: result} |
| 322 | } |
| 323 | |
| 324 | func convertEvent(ev core.Event) wire.TimeEvent { |
| 325 | return wire.TimeEvent{ |
| 326 | Time: convertTimestamp(ev.At()), |
| 327 | Annotation: convertAnnotation(ev), |
| 328 | } |
| 329 | } |
| 330 | |
| 331 | func getAnnotationDescription(ev core.Event) (string, int) { |
| 332 | l := ev.Label(0) |
| 333 | if l.Key() != keys.Msg { |
| 334 | return "", 0 |
| 335 | } |
| 336 | if msg := keys.Msg.From(l); msg != "" { |
| 337 | return msg, 1 |
| 338 | } |
| 339 | l = ev.Label(1) |
| 340 | if l.Key() != keys.Err { |
| 341 | return "", 1 |
| 342 | } |
| 343 | if err := keys.Err.From(l); err != nil { |
| 344 | return err.Error(), 2 |
| 345 | } |
| 346 | return "", 2 |
| 347 | } |
| 348 | |
| 349 | func convertAnnotation(ev core.Event) *wire.Annotation { |
| 350 | description, index := getAnnotationDescription(ev) |
| 351 | if _, l := skipToValidLabel(ev, index); !l.Valid() && description == "" { |
| 352 | return nil |
| 353 | } |
| 354 | return &wire.Annotation{ |
| 355 | Description: toTruncatableString(description), |
| 356 | Attributes: convertAttributes(ev, index), |
| 357 | } |
| 358 | } |
| 359 |
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