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Diffstat (limited to 'vendor/golang.org/x/net/trace/trace.go')
| -rw-r--r-- | vendor/golang.org/x/net/trace/trace.go | 1111 |
1 files changed, 0 insertions, 1111 deletions
diff --git a/vendor/golang.org/x/net/trace/trace.go b/vendor/golang.org/x/net/trace/trace.go deleted file mode 100644 index f00d869..0000000 --- a/vendor/golang.org/x/net/trace/trace.go +++ /dev/null @@ -1,1111 +0,0 @@ -// Copyright 2015 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -/* -Package trace implements tracing of requests and long-lived objects. -It exports HTTP interfaces on /debug/requests and /debug/events. - -A trace.Trace provides tracing for short-lived objects, usually requests. -A request handler might be implemented like this: - - func fooHandler(w http.ResponseWriter, req *http.Request) { - tr := trace.New("mypkg.Foo", req.URL.Path) - defer tr.Finish() - ... - tr.LazyPrintf("some event %q happened", str) - ... - if err := somethingImportant(); err != nil { - tr.LazyPrintf("somethingImportant failed: %v", err) - tr.SetError() - } - } - -The /debug/requests HTTP endpoint organizes the traces by family, -errors, and duration. It also provides histogram of request duration -for each family. - -A trace.EventLog provides tracing for long-lived objects, such as RPC -connections. - - // A Fetcher fetches URL paths for a single domain. - type Fetcher struct { - domain string - events trace.EventLog - } - - func NewFetcher(domain string) *Fetcher { - return &Fetcher{ - domain, - trace.NewEventLog("mypkg.Fetcher", domain), - } - } - - func (f *Fetcher) Fetch(path string) (string, error) { - resp, err := http.Get("http://" + f.domain + "/" + path) - if err != nil { - f.events.Errorf("Get(%q) = %v", path, err) - return "", err - } - f.events.Printf("Get(%q) = %s", path, resp.Status) - ... - } - - func (f *Fetcher) Close() error { - f.events.Finish() - return nil - } - -The /debug/events HTTP endpoint organizes the event logs by family and -by time since the last error. The expanded view displays recent log -entries and the log's call stack. -*/ -package trace // import "golang.org/x/net/trace" - -import ( - "bytes" - "fmt" - "html/template" - "io" - "log" - "net" - "net/http" - "net/url" - "runtime" - "sort" - "strconv" - "sync" - "sync/atomic" - "time" - - "golang.org/x/net/internal/timeseries" -) - -// DebugUseAfterFinish controls whether to debug uses of Trace values after finishing. -// FOR DEBUGGING ONLY. This will slow down the program. -var DebugUseAfterFinish = false - -// AuthRequest determines whether a specific request is permitted to load the -// /debug/requests or /debug/events pages. -// -// It returns two bools; the first indicates whether the page may be viewed at all, -// and the second indicates whether sensitive events will be shown. -// -// AuthRequest may be replaced by a program to customize its authorization requirements. -// -// The default AuthRequest function returns (true, true) if and only if the request -// comes from localhost/127.0.0.1/[::1]. -var AuthRequest = func(req *http.Request) (any, sensitive bool) { - // RemoteAddr is commonly in the form "IP" or "IP:port". - // If it is in the form "IP:port", split off the port. - host, _, err := net.SplitHostPort(req.RemoteAddr) - if err != nil { - host = req.RemoteAddr - } - switch host { - case "localhost", "127.0.0.1", "::1": - return true, true - default: - return false, false - } -} - -func init() { - _, pat := http.DefaultServeMux.Handler(&http.Request{URL: &url.URL{Path: "/debug/requests"}}) - if pat != "" { - panic("/debug/requests is already registered. You may have two independent copies of " + - "golang.org/x/net/trace in your binary, trying to maintain separate state. This may " + - "involve a vendored copy of golang.org/x/net/trace.") - } - - // TODO(jbd): Serve Traces from /debug/traces in the future? - // There is no requirement for a request to be present to have traces. - http.HandleFunc("/debug/requests", Traces) - http.HandleFunc("/debug/events", Events) -} - -// Traces responds with traces from the program. -// The package initialization registers it in http.DefaultServeMux -// at /debug/requests. -// -// It performs authorization by running AuthRequest. -func Traces(w http.ResponseWriter, req *http.Request) { - any, sensitive := AuthRequest(req) - if !any { - http.Error(w, "not allowed", http.StatusUnauthorized) - return - } - w.Header().Set("Content-Type", "text/html; charset=utf-8") - Render(w, req, sensitive) -} - -// Events responds with a page of events collected by EventLogs. -// The package initialization registers it in http.DefaultServeMux -// at /debug/events. -// -// It performs authorization by running AuthRequest. -func Events(w http.ResponseWriter, req *http.Request) { - any, sensitive := AuthRequest(req) - if !any { - http.Error(w, "not allowed", http.StatusUnauthorized) - return - } - w.Header().Set("Content-Type", "text/html; charset=utf-8") - RenderEvents(w, req, sensitive) -} - -// Render renders the HTML page typically served at /debug/requests. -// It does not do any auth checking. The request may be nil. -// -// Most users will use the Traces handler. -func Render(w io.Writer, req *http.Request, sensitive bool) { - data := &struct { - Families []string - ActiveTraceCount map[string]int - CompletedTraces map[string]*family - - // Set when a bucket has been selected. - Traces traceList - Family string - Bucket int - Expanded bool - Traced bool - Active bool - ShowSensitive bool // whether to show sensitive events - - Histogram template.HTML - HistogramWindow string // e.g. "last minute", "last hour", "all time" - - // If non-zero, the set of traces is a partial set, - // and this is the total number. - Total int - }{ - CompletedTraces: completedTraces, - } - - data.ShowSensitive = sensitive - if req != nil { - // Allow show_sensitive=0 to force hiding of sensitive data for testing. - // This only goes one way; you can't use show_sensitive=1 to see things. - if req.FormValue("show_sensitive") == "0" { - data.ShowSensitive = false - } - - if exp, err := strconv.ParseBool(req.FormValue("exp")); err == nil { - data.Expanded = exp - } - if exp, err := strconv.ParseBool(req.FormValue("rtraced")); err == nil { - data.Traced = exp - } - } - - completedMu.RLock() - data.Families = make([]string, 0, len(completedTraces)) - for fam := range completedTraces { - data.Families = append(data.Families, fam) - } - completedMu.RUnlock() - sort.Strings(data.Families) - - // We are careful here to minimize the time spent locking activeMu, - // since that lock is required every time an RPC starts and finishes. - data.ActiveTraceCount = make(map[string]int, len(data.Families)) - activeMu.RLock() - for fam, s := range activeTraces { - data.ActiveTraceCount[fam] = s.Len() - } - activeMu.RUnlock() - - var ok bool - data.Family, data.Bucket, ok = parseArgs(req) - switch { - case !ok: - // No-op - case data.Bucket == -1: - data.Active = true - n := data.ActiveTraceCount[data.Family] - data.Traces = getActiveTraces(data.Family) - if len(data.Traces) < n { - data.Total = n - } - case data.Bucket < bucketsPerFamily: - if b := lookupBucket(data.Family, data.Bucket); b != nil { - data.Traces = b.Copy(data.Traced) - } - default: - if f := getFamily(data.Family, false); f != nil { - var obs timeseries.Observable - f.LatencyMu.RLock() - switch o := data.Bucket - bucketsPerFamily; o { - case 0: - obs = f.Latency.Minute() - data.HistogramWindow = "last minute" - case 1: - obs = f.Latency.Hour() - data.HistogramWindow = "last hour" - case 2: - obs = f.Latency.Total() - data.HistogramWindow = "all time" - } - f.LatencyMu.RUnlock() - if obs != nil { - data.Histogram = obs.(*histogram).html() - } - } - } - - if data.Traces != nil { - defer data.Traces.Free() - sort.Sort(data.Traces) - } - - completedMu.RLock() - defer completedMu.RUnlock() - if err := pageTmpl().ExecuteTemplate(w, "Page", data); err != nil { - log.Printf("net/trace: Failed executing template: %v", err) - } -} - -func parseArgs(req *http.Request) (fam string, b int, ok bool) { - if req == nil { - return "", 0, false - } - fam, bStr := req.FormValue("fam"), req.FormValue("b") - if fam == "" || bStr == "" { - return "", 0, false - } - b, err := strconv.Atoi(bStr) - if err != nil || b < -1 { - return "", 0, false - } - - return fam, b, true -} - -func lookupBucket(fam string, b int) *traceBucket { - f := getFamily(fam, false) - if f == nil || b < 0 || b >= len(f.Buckets) { - return nil - } - return f.Buckets[b] -} - -type contextKeyT string - -var contextKey = contextKeyT("golang.org/x/net/trace.Trace") - -// Trace represents an active request. -type Trace interface { - // LazyLog adds x to the event log. It will be evaluated each time the - // /debug/requests page is rendered. Any memory referenced by x will be - // pinned until the trace is finished and later discarded. - LazyLog(x fmt.Stringer, sensitive bool) - - // LazyPrintf evaluates its arguments with fmt.Sprintf each time the - // /debug/requests page is rendered. Any memory referenced by a will be - // pinned until the trace is finished and later discarded. - LazyPrintf(format string, a ...interface{}) - - // SetError declares that this trace resulted in an error. - SetError() - - // SetRecycler sets a recycler for the trace. - // f will be called for each event passed to LazyLog at a time when - // it is no longer required, whether while the trace is still active - // and the event is discarded, or when a completed trace is discarded. - SetRecycler(f func(interface{})) - - // SetTraceInfo sets the trace info for the trace. - // This is currently unused. - SetTraceInfo(traceID, spanID uint64) - - // SetMaxEvents sets the maximum number of events that will be stored - // in the trace. This has no effect if any events have already been - // added to the trace. - SetMaxEvents(m int) - - // Finish declares that this trace is complete. - // The trace should not be used after calling this method. - Finish() -} - -type lazySprintf struct { - format string - a []interface{} -} - -func (l *lazySprintf) String() string { - return fmt.Sprintf(l.format, l.a...) -} - -// New returns a new Trace with the specified family and title. -func New(family, title string) Trace { - tr := newTrace() - tr.ref() - tr.Family, tr.Title = family, title - tr.Start = time.Now() - tr.maxEvents = maxEventsPerTrace - tr.events = tr.eventsBuf[:0] - - activeMu.RLock() - s := activeTraces[tr.Family] - activeMu.RUnlock() - if s == nil { - activeMu.Lock() - s = activeTraces[tr.Family] // check again - if s == nil { - s = new(traceSet) - activeTraces[tr.Family] = s - } - activeMu.Unlock() - } - s.Add(tr) - - // Trigger allocation of the completed trace structure for this family. - // This will cause the family to be present in the request page during - // the first trace of this family. We don't care about the return value, - // nor is there any need for this to run inline, so we execute it in its - // own goroutine, but only if the family isn't allocated yet. - completedMu.RLock() - if _, ok := completedTraces[tr.Family]; !ok { - go allocFamily(tr.Family) - } - completedMu.RUnlock() - - return tr -} - -func (tr *trace) Finish() { - elapsed := time.Now().Sub(tr.Start) - tr.mu.Lock() - tr.Elapsed = elapsed - tr.mu.Unlock() - - if DebugUseAfterFinish { - buf := make([]byte, 4<<10) // 4 KB should be enough - n := runtime.Stack(buf, false) - tr.finishStack = buf[:n] - } - - activeMu.RLock() - m := activeTraces[tr.Family] - activeMu.RUnlock() - m.Remove(tr) - - f := getFamily(tr.Family, true) - tr.mu.RLock() // protects tr fields in Cond.match calls - for _, b := range f.Buckets { - if b.Cond.match(tr) { - b.Add(tr) - } - } - tr.mu.RUnlock() - - // Add a sample of elapsed time as microseconds to the family's timeseries - h := new(histogram) - h.addMeasurement(elapsed.Nanoseconds() / 1e3) - f.LatencyMu.Lock() - f.Latency.Add(h) - f.LatencyMu.Unlock() - - tr.unref() // matches ref in New -} - -const ( - bucketsPerFamily = 9 - tracesPerBucket = 10 - maxActiveTraces = 20 // Maximum number of active traces to show. - maxEventsPerTrace = 10 - numHistogramBuckets = 38 -) - -var ( - // The active traces. - activeMu sync.RWMutex - activeTraces = make(map[string]*traceSet) // family -> traces - - // Families of completed traces. - completedMu sync.RWMutex - completedTraces = make(map[string]*family) // family -> traces -) - -type traceSet struct { - mu sync.RWMutex - m map[*trace]bool - - // We could avoid the entire map scan in FirstN by having a slice of all the traces - // ordered by start time, and an index into that from the trace struct, with a periodic - // repack of the slice after enough traces finish; we could also use a skip list or similar. - // However, that would shift some of the expense from /debug/requests time to RPC time, - // which is probably the wrong trade-off. -} - -func (ts *traceSet) Len() int { - ts.mu.RLock() - defer ts.mu.RUnlock() - return len(ts.m) -} - -func (ts *traceSet) Add(tr *trace) { - ts.mu.Lock() - if ts.m == nil { - ts.m = make(map[*trace]bool) - } - ts.m[tr] = true - ts.mu.Unlock() -} - -func (ts *traceSet) Remove(tr *trace) { - ts.mu.Lock() - delete(ts.m, tr) - ts.mu.Unlock() -} - -// FirstN returns the first n traces ordered by time. -func (ts *traceSet) FirstN(n int) traceList { - ts.mu.RLock() - defer ts.mu.RUnlock() - - if n > len(ts.m) { - n = len(ts.m) - } - trl := make(traceList, 0, n) - - // Fast path for when no selectivity is needed. - if n == len(ts.m) { - for tr := range ts.m { - tr.ref() - trl = append(trl, tr) - } - sort.Sort(trl) - return trl - } - - // Pick the oldest n traces. - // This is inefficient. See the comment in the traceSet struct. - for tr := range ts.m { - // Put the first n traces into trl in the order they occur. - // When we have n, sort trl, and thereafter maintain its order. - if len(trl) < n { - tr.ref() - trl = append(trl, tr) - if len(trl) == n { - // This is guaranteed to happen exactly once during this loop. - sort.Sort(trl) - } - continue - } - if tr.Start.After(trl[n-1].Start) { - continue - } - - // Find where to insert this one. - tr.ref() - i := sort.Search(n, func(i int) bool { return trl[i].Start.After(tr.Start) }) - trl[n-1].unref() - copy(trl[i+1:], trl[i:]) - trl[i] = tr - } - - return trl -} - -func getActiveTraces(fam string) traceList { - activeMu.RLock() - s := activeTraces[fam] - activeMu.RUnlock() - if s == nil { - return nil - } - return s.FirstN(maxActiveTraces) -} - -func getFamily(fam string, allocNew bool) *family { - completedMu.RLock() - f := completedTraces[fam] - completedMu.RUnlock() - if f == nil && allocNew { - f = allocFamily(fam) - } - return f -} - -func allocFamily(fam string) *family { - completedMu.Lock() - defer completedMu.Unlock() - f := completedTraces[fam] - if f == nil { - f = newFamily() - completedTraces[fam] = f - } - return f -} - -// family represents a set of trace buckets and associated latency information. -type family struct { - // traces may occur in multiple buckets. - Buckets [bucketsPerFamily]*traceBucket - - // latency time series - LatencyMu sync.RWMutex - Latency *timeseries.MinuteHourSeries -} - -func newFamily() *family { - return &family{ - Buckets: [bucketsPerFamily]*traceBucket{ - {Cond: minCond(0)}, - {Cond: minCond(50 * time.Millisecond)}, - {Cond: minCond(100 * time.Millisecond)}, - {Cond: minCond(200 * time.Millisecond)}, - {Cond: minCond(500 * time.Millisecond)}, - {Cond: minCond(1 * time.Second)}, - {Cond: minCond(10 * time.Second)}, - {Cond: minCond(100 * time.Second)}, - {Cond: errorCond{}}, - }, - Latency: timeseries.NewMinuteHourSeries(func() timeseries.Observable { return new(histogram) }), - } -} - -// traceBucket represents a size-capped bucket of historic traces, -// along with a condition for a trace to belong to the bucket. -type traceBucket struct { - Cond cond - - // Ring buffer implementation of a fixed-size FIFO queue. - mu sync.RWMutex - buf [tracesPerBucket]*trace - start int // < tracesPerBucket - length int // <= tracesPerBucket -} - -func (b *traceBucket) Add(tr *trace) { - b.mu.Lock() - defer b.mu.Unlock() - - i := b.start + b.length - if i >= tracesPerBucket { - i -= tracesPerBucket - } - if b.length == tracesPerBucket { - // "Remove" an element from the bucket. - b.buf[i].unref() - b.start++ - if b.start == tracesPerBucket { - b.start = 0 - } - } - b.buf[i] = tr - if b.length < tracesPerBucket { - b.length++ - } - tr.ref() -} - -// Copy returns a copy of the traces in the bucket. -// If tracedOnly is true, only the traces with trace information will be returned. -// The logs will be ref'd before returning; the caller should call -// the Free method when it is done with them. -// TODO(dsymonds): keep track of traced requests in separate buckets. -func (b *traceBucket) Copy(tracedOnly bool) traceList { - b.mu.RLock() - defer b.mu.RUnlock() - - trl := make(traceList, 0, b.length) - for i, x := 0, b.start; i < b.length; i++ { - tr := b.buf[x] - if !tracedOnly || tr.spanID != 0 { - tr.ref() - trl = append(trl, tr) - } - x++ - if x == b.length { - x = 0 - } - } - return trl -} - -func (b *traceBucket) Empty() bool { - b.mu.RLock() - defer b.mu.RUnlock() - return b.length == 0 -} - -// cond represents a condition on a trace. -type cond interface { - match(t *trace) bool - String() string -} - -type minCond time.Duration - -func (m minCond) match(t *trace) bool { return t.Elapsed >= time.Duration(m) } -func (m minCond) String() string { return fmt.Sprintf("≥%gs", time.Duration(m).Seconds()) } - -type errorCond struct{} - -func (e errorCond) match(t *trace) bool { return t.IsError } -func (e errorCond) String() string { return "errors" } - -type traceList []*trace - -// Free calls unref on each element of the list. -func (trl traceList) Free() { - for _, t := range trl { - t.unref() - } -} - -// traceList may be sorted in reverse chronological order. -func (trl traceList) Len() int { return len(trl) } -func (trl traceList) Less(i, j int) bool { return trl[i].Start.After(trl[j].Start) } -func (trl traceList) Swap(i, j int) { trl[i], trl[j] = trl[j], trl[i] } - -// An event is a timestamped log entry in a trace. -type event struct { - When time.Time - Elapsed time.Duration // since previous event in trace - NewDay bool // whether this event is on a different day to the previous event - Recyclable bool // whether this event was passed via LazyLog - Sensitive bool // whether this event contains sensitive information - What interface{} // string or fmt.Stringer -} - -// WhenString returns a string representation of the elapsed time of the event. -// It will include the date if midnight was crossed. -func (e event) WhenString() string { - if e.NewDay { - return e.When.Format("2006/01/02 15:04:05.000000") - } - return e.When.Format("15:04:05.000000") -} - -// discarded represents a number of discarded events. -// It is stored as *discarded to make it easier to update in-place. -type discarded int - -func (d *discarded) String() string { - return fmt.Sprintf("(%d events discarded)", int(*d)) -} - -// trace represents an active or complete request, -// either sent or received by this program. -type trace struct { - // Family is the top-level grouping of traces to which this belongs. - Family string - - // Title is the title of this trace. - Title string - - // Start time of the this trace. - Start time.Time - - mu sync.RWMutex - events []event // Append-only sequence of events (modulo discards). - maxEvents int - recycler func(interface{}) - IsError bool // Whether this trace resulted in an error. - Elapsed time.Duration // Elapsed time for this trace, zero while active. - traceID uint64 // Trace information if non-zero. - spanID uint64 - - refs int32 // how many buckets this is in - disc discarded // scratch space to avoid allocation - - finishStack []byte // where finish was called, if DebugUseAfterFinish is set - - eventsBuf [4]event // preallocated buffer in case we only log a few events -} - -func (tr *trace) reset() { - // Clear all but the mutex. Mutexes may not be copied, even when unlocked. - tr.Family = "" - tr.Title = "" - tr.Start = time.Time{} - - tr.mu.Lock() - tr.Elapsed = 0 - tr.traceID = 0 - tr.spanID = 0 - tr.IsError = false - tr.maxEvents = 0 - tr.events = nil - tr.recycler = nil - tr.mu.Unlock() - - tr.refs = 0 - tr.disc = 0 - tr.finishStack = nil - for i := range tr.eventsBuf { - tr.eventsBuf[i] = event{} - } -} - -// delta returns the elapsed time since the last event or the trace start, -// and whether it spans midnight. -// L >= tr.mu -func (tr *trace) delta(t time.Time) (time.Duration, bool) { - if len(tr.events) == 0 { - return t.Sub(tr.Start), false - } - prev := tr.events[len(tr.events)-1].When - return t.Sub(prev), prev.Day() != t.Day() -} - -func (tr *trace) addEvent(x interface{}, recyclable, sensitive bool) { - if DebugUseAfterFinish && tr.finishStack != nil { - buf := make([]byte, 4<<10) // 4 KB should be enough - n := runtime.Stack(buf, false) - log.Printf("net/trace: trace used after finish:\nFinished at:\n%s\nUsed at:\n%s", tr.finishStack, buf[:n]) - } - - /* - NOTE TO DEBUGGERS - - If you are here because your program panicked in this code, - it is almost definitely the fault of code using this package, - and very unlikely to be the fault of this code. - - The most likely scenario is that some code elsewhere is using - a trace.Trace after its Finish method is called. - You can temporarily set the DebugUseAfterFinish var - to help discover where that is; do not leave that var set, - since it makes this package much less efficient. - */ - - e := event{When: time.Now(), What: x, Recyclable: recyclable, Sensitive: sensitive} - tr.mu.Lock() - e.Elapsed, e.NewDay = tr.delta(e.When) - if len(tr.events) < tr.maxEvents { - tr.events = append(tr.events, e) - } else { - // Discard the middle events. - di := int((tr.maxEvents - 1) / 2) - if d, ok := tr.events[di].What.(*discarded); ok { - (*d)++ - } else { - // disc starts at two to count for the event it is replacing, - // plus the next one that we are about to drop. - tr.disc = 2 - if tr.recycler != nil && tr.events[di].Recyclable { - go tr.recycler(tr.events[di].What) - } - tr.events[di].What = &tr.disc - } - // The timestamp of the discarded meta-event should be - // the time of the last event it is representing. - tr.events[di].When = tr.events[di+1].When - - if tr.recycler != nil && tr.events[di+1].Recyclable { - go tr.recycler(tr.events[di+1].What) - } - copy(tr.events[di+1:], tr.events[di+2:]) - tr.events[tr.maxEvents-1] = e - } - tr.mu.Unlock() -} - -func (tr *trace) LazyLog(x fmt.Stringer, sensitive bool) { - tr.addEvent(x, true, sensitive) -} - -func (tr *trace) LazyPrintf(format string, a ...interface{}) { - tr.addEvent(&lazySprintf{format, a}, false, false) -} - -func (tr *trace) SetError() { - tr.mu.Lock() - tr.IsError = true - tr.mu.Unlock() -} - -func (tr *trace) SetRecycler(f func(interface{})) { - tr.mu.Lock() - tr.recycler = f - tr.mu.Unlock() -} - -func (tr *trace) SetTraceInfo(traceID, spanID uint64) { - tr.mu.Lock() - tr.traceID, tr.spanID = traceID, spanID - tr.mu.Unlock() -} - -func (tr *trace) SetMaxEvents(m int) { - tr.mu.Lock() - // Always keep at least three events: first, discarded count, last. - if len(tr.events) == 0 && m > 3 { - tr.maxEvents = m - } - tr.mu.Unlock() -} - -func (tr *trace) ref() { - atomic.AddInt32(&tr.refs, 1) -} - -func (tr *trace) unref() { - if atomic.AddInt32(&tr.refs, -1) == 0 { - tr.mu.RLock() - if tr.recycler != nil { - // freeTrace clears tr, so we hold tr.recycler and tr.events here. - go func(f func(interface{}), es []event) { - for _, e := range es { - if e.Recyclable { - f(e.What) - } - } - }(tr.recycler, tr.events) - } - tr.mu.RUnlock() - - freeTrace(tr) - } -} - -func (tr *trace) When() string { - return tr.Start.Format("2006/01/02 15:04:05.000000") -} - -func (tr *trace) ElapsedTime() string { - tr.mu.RLock() - t := tr.Elapsed - tr.mu.RUnlock() - - if t == 0 { - // Active trace. - t = time.Since(tr.Start) - } - return fmt.Sprintf("%.6f", t.Seconds()) -} - -func (tr *trace) Events() []event { - tr.mu.RLock() - defer tr.mu.RUnlock() - return tr.events -} - -var traceFreeList = make(chan *trace, 1000) // TODO(dsymonds): Use sync.Pool? - -// newTrace returns a trace ready to use. -func newTrace() *trace { - select { - case tr := <-traceFreeList: - return tr - default: - return new(trace) - } -} - -// freeTrace adds tr to traceFreeList if there's room. -// This is non-blocking. -func freeTrace(tr *trace) { - if DebugUseAfterFinish { - return // never reuse - } - tr.reset() - select { - case traceFreeList <- tr: - default: - } -} - -func elapsed(d time.Duration) string { - b := []byte(fmt.Sprintf("%.6f", d.Seconds())) - - // For subsecond durations, blank all zeros before decimal point, - // and all zeros between the decimal point and the first non-zero digit. - if d < time.Second { - dot := bytes.IndexByte(b, '.') - for i := 0; i < dot; i++ { - b[i] = ' ' - } - for i := dot + 1; i < len(b); i++ { - if b[i] == '0' { - b[i] = ' ' - } else { - break - } - } - } - - return string(b) -} - -var pageTmplCache *template.Template -var pageTmplOnce sync.Once - -func pageTmpl() *template.Template { - pageTmplOnce.Do(func() { - pageTmplCache = template.Must(template.New("Page").Funcs(template.FuncMap{ - "elapsed": elapsed, - "add": func(a, b int) int { return a + b }, - }).Parse(pageHTML)) - }) - return pageTmplCache -} - -const pageHTML = ` -{{template "Prolog" .}} -{{template "StatusTable" .}} -{{template "Epilog" .}} - -{{define "Prolog"}} -<html> - <head> - <title>/debug/requests</title> - <style type="text/css"> - body { - font-family: sans-serif; - } - table#tr-status td.family { - padding-right: 2em; - } - table#tr-status td.active { - padding-right: 1em; - } - table#tr-status td.latency-first { - padding-left: 1em; - } - table#tr-status td.empty { - color: #aaa; - } - table#reqs { - margin-top: 1em; - } - table#reqs tr.first { - {{if $.Expanded}}font-weight: bold;{{end}} - } - table#reqs td { - font-family: monospace; - } - table#reqs td.when { - text-align: right; - white-space: nowrap; - } - table#reqs td.elapsed { - padding: 0 0.5em; - text-align: right; - white-space: pre; - width: 10em; - } - address { - font-size: smaller; - margin-top: 5em; - } - </style> - </head> - <body> - -<h1>/debug/requests</h1> -{{end}} {{/* end of Prolog */}} - -{{define "StatusTable"}} -<table id="tr-status"> - {{range $fam := .Families}} - <tr> - <td class="family">{{$fam}}</td> - - {{$n := index $.ActiveTraceCount $fam}} - <td class="active {{if not $n}}empty{{end}}"> - {{if $n}}<a href="?fam={{$fam}}&b=-1{{if $.Expanded}}&exp=1{{end}}">{{end}} - [{{$n}} active] - {{if $n}}</a>{{end}} - </td> - - {{$f := index $.CompletedTraces $fam}} - {{range $i, $b := $f.Buckets}} - {{$empty := $b.Empty}} - <td {{if $empty}}class="empty"{{end}}> - {{if not $empty}}<a href="?fam={{$fam}}&b={{$i}}{{if $.Expanded}}&exp=1{{end}}">{{end}} - [{{.Cond}}] - {{if not $empty}}</a>{{end}} - </td> - {{end}} - - {{$nb := len $f.Buckets}} - <td class="latency-first"> - <a href="?fam={{$fam}}&b={{$nb}}">[minute]</a> - </td> - <td> - <a href="?fam={{$fam}}&b={{add $nb 1}}">[hour]</a> - </td> - <td> - <a href="?fam={{$fam}}&b={{add $nb 2}}">[total]</a> - </td> - - </tr> - {{end}} -</table> -{{end}} {{/* end of StatusTable */}} - -{{define "Epilog"}} -{{if $.Traces}} -<hr /> -<h3>Family: {{$.Family}}</h3> - -{{if or $.Expanded $.Traced}} - <a href="?fam={{$.Family}}&b={{$.Bucket}}">[Normal/Summary]</a> -{{else}} - [Normal/Summary] -{{end}} - -{{if or (not $.Expanded) $.Traced}} - <a href="?fam={{$.Family}}&b={{$.Bucket}}&exp=1">[Normal/Expanded]</a> -{{else}} - [Normal/Expanded] -{{end}} - -{{if not $.Active}} - {{if or $.Expanded (not $.Traced)}} - <a href="?fam={{$.Family}}&b={{$.Bucket}}&rtraced=1">[Traced/Summary]</a> - {{else}} - [Traced/Summary] - {{end}} - {{if or (not $.Expanded) (not $.Traced)}} - <a href="?fam={{$.Family}}&b={{$.Bucket}}&exp=1&rtraced=1">[Traced/Expanded]</a> - {{else}} - [Traced/Expanded] - {{end}} -{{end}} - -{{if $.Total}} -<p><em>Showing <b>{{len $.Traces}}</b> of <b>{{$.Total}}</b> traces.</em></p> -{{end}} - -<table id="reqs"> - <caption> - {{if $.Active}}Active{{else}}Completed{{end}} Requests - </caption> - <tr><th>When</th><th>Elapsed (s)</th></tr> - {{range $tr := $.Traces}} - <tr class="first"> - <td class="when">{{$tr.When}}</td> - <td class="elapsed">{{$tr.ElapsedTime}}</td> - <td>{{$tr.Title}}</td> - {{/* TODO: include traceID/spanID */}} - </tr> - {{if $.Expanded}} - {{range $tr.Events}} - <tr> - <td class="when">{{.WhenString}}</td> - <td class="elapsed">{{elapsed .Elapsed}}</td> - <td>{{if or $.ShowSensitive (not .Sensitive)}}... {{.What}}{{else}}<em>[redacted]</em>{{end}}</td> - </tr> - {{end}} - {{end}} - {{end}} -</table> -{{end}} {{/* if $.Traces */}} - -{{if $.Histogram}} -<h4>Latency (µs) of {{$.Family}} over {{$.HistogramWindow}}</h4> -{{$.Histogram}} -{{end}} {{/* if $.Histogram */}} - - </body> -</html> -{{end}} {{/* end of Epilog */}} -` |