From de6d2c524430287c699aaa898c1325da6afea539 Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Wed, 20 Jun 2018 22:39:07 +0100 Subject: Update dependencies --- vendor/go.opencensus.io/stats/view/worker.go | 233 +++++++++++++++++++++++++++ 1 file changed, 233 insertions(+) create mode 100644 vendor/go.opencensus.io/stats/view/worker.go (limited to 'vendor/go.opencensus.io/stats/view/worker.go') diff --git a/vendor/go.opencensus.io/stats/view/worker.go b/vendor/go.opencensus.io/stats/view/worker.go new file mode 100644 index 0000000..ba9d7fc --- /dev/null +++ b/vendor/go.opencensus.io/stats/view/worker.go @@ -0,0 +1,233 @@ +// Copyright 2017, OpenCensus Authors +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// + +package view + +import ( + "fmt" + "time" + + "go.opencensus.io/stats" + "go.opencensus.io/stats/internal" + "go.opencensus.io/tag" +) + +func init() { + defaultWorker = newWorker() + go defaultWorker.start() + internal.DefaultRecorder = record +} + +type measureRef struct { + measure string + views map[*viewInternal]struct{} +} + +type worker struct { + measures map[string]*measureRef + views map[string]*viewInternal + startTimes map[*viewInternal]time.Time + + timer *time.Ticker + c chan command + quit, done chan bool +} + +var defaultWorker *worker + +var defaultReportingDuration = 10 * time.Second + +// Find returns a subscribed view associated with this name. +// If no subscribed view is found, nil is returned. +func Find(name string) (v *View) { + req := &getViewByNameReq{ + name: name, + c: make(chan *getViewByNameResp), + } + defaultWorker.c <- req + resp := <-req.c + return resp.v +} + +// Register begins collecting data for the given views. +// Once a view is subscribed, it reports data to the registered exporters. +func Register(views ...*View) error { + for _, v := range views { + if err := v.canonicalize(); err != nil { + return err + } + } + req := ®isterViewReq{ + views: views, + err: make(chan error), + } + defaultWorker.c <- req + return <-req.err +} + +// Unregister the given views. Data will not longer be exported for these views +// after Unregister returns. +// It is not necessary to unregister from views you expect to collect for the +// duration of your program execution. +func Unregister(views ...*View) { + names := make([]string, len(views)) + for i := range views { + names[i] = views[i].Name + } + req := &unregisterFromViewReq{ + views: names, + done: make(chan struct{}), + } + defaultWorker.c <- req + <-req.done +} + +// RetrieveData gets a snapshot of the data collected for the the view registered +// with the given name. It is intended for testing only. +func RetrieveData(viewName string) ([]*Row, error) { + req := &retrieveDataReq{ + now: time.Now(), + v: viewName, + c: make(chan *retrieveDataResp), + } + defaultWorker.c <- req + resp := <-req.c + return resp.rows, resp.err +} + +func record(tags *tag.Map, ms interface{}) { + req := &recordReq{ + tm: tags, + ms: ms.([]stats.Measurement), + } + defaultWorker.c <- req +} + +// SetReportingPeriod sets the interval between reporting aggregated views in +// the program. If duration is less than or +// equal to zero, it enables the default behavior. +func SetReportingPeriod(d time.Duration) { + // TODO(acetechnologist): ensure that the duration d is more than a certain + // value. e.g. 1s + req := &setReportingPeriodReq{ + d: d, + c: make(chan bool), + } + defaultWorker.c <- req + <-req.c // don't return until the timer is set to the new duration. +} + +func newWorker() *worker { + return &worker{ + measures: make(map[string]*measureRef), + views: make(map[string]*viewInternal), + startTimes: make(map[*viewInternal]time.Time), + timer: time.NewTicker(defaultReportingDuration), + c: make(chan command, 1024), + quit: make(chan bool), + done: make(chan bool), + } +} + +func (w *worker) start() { + for { + select { + case cmd := <-w.c: + cmd.handleCommand(w) + case <-w.timer.C: + w.reportUsage(time.Now()) + case <-w.quit: + w.timer.Stop() + close(w.c) + w.done <- true + return + } + } +} + +func (w *worker) stop() { + w.quit <- true + <-w.done +} + +func (w *worker) getMeasureRef(name string) *measureRef { + if mr, ok := w.measures[name]; ok { + return mr + } + mr := &measureRef{ + measure: name, + views: make(map[*viewInternal]struct{}), + } + w.measures[name] = mr + return mr +} + +func (w *worker) tryRegisterView(v *View) (*viewInternal, error) { + vi, err := newViewInternal(v) + if err != nil { + return nil, err + } + if x, ok := w.views[vi.view.Name]; ok { + if !x.view.same(vi.view) { + return nil, fmt.Errorf("cannot subscribe view %q; a different view with the same name is already subscribed", v.Name) + } + + // the view is already registered so there is nothing to do and the + // command is considered successful. + return x, nil + } + w.views[vi.view.Name] = vi + ref := w.getMeasureRef(vi.view.Measure.Name()) + ref.views[vi] = struct{}{} + return vi, nil +} + +func (w *worker) reportUsage(now time.Time) { + for _, v := range w.views { + if !v.isSubscribed() { + continue + } + rows := v.collectedRows() + _, ok := w.startTimes[v] + if !ok { + w.startTimes[v] = now + } + // Make sure collector is never going + // to mutate the exported data. + rows = deepCopyRowData(rows) + viewData := &Data{ + View: v.view, + Start: w.startTimes[v], + End: time.Now(), + Rows: rows, + } + exportersMu.Lock() + for e := range exporters { + e.ExportView(viewData) + } + exportersMu.Unlock() + } +} + +func deepCopyRowData(rows []*Row) []*Row { + newRows := make([]*Row, 0, len(rows)) + for _, r := range rows { + newRows = append(newRows, &Row{ + Data: r.Data.clone(), + Tags: r.Tags, + }) + } + return newRows +} -- cgit v1.2.3