Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
Showing
9 changed files
with
150 additions
and
235 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file was deleted.
Oops, something went wrong.
This file was deleted.
Oops, something went wrong.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -1,171 +1,19 @@ | ||
| package sentry | ||
|
|
||
| import ( | ||
| "fmt" | ||
|
|
||
| "github.com/getsentry/sentry-go/internal/crypto/randutil" | ||
| ) | ||
|
|
||
| // A TracesSampler makes sampling decisions for spans. | ||
| // | ||
| // In addition to the sampling context passed to the Sample method, | ||
| // implementations may keep and use internal state to make decisions. | ||
| // | ||
| // Sampling is one of the last steps when starting a new span, such that the | ||
| // sampler can inspect most of the state of the span to make a decision. | ||
| // | ||
| // Implementations must be safe for concurrent use by multiple goroutines. | ||
| type TracesSampler interface { | ||
| Sample(ctx SamplingContext) Sampled | ||
| } | ||
|
|
||
| // Implementation note: | ||
| // | ||
| // TracesSampler.Sample return type is Sampled (instead of bool or float64), so | ||
| // that we can compose samplers by letting a sampler return SampledUndefined to | ||
| // defer the decision to the next sampler. | ||
| // | ||
| // For example, a hypothetical InheritFromParentSampler would return | ||
| // SampledUndefined if there is no parent span in the SamplingContext, deferring | ||
| // the sampling decision to another sampler, like a UniformSampler. | ||
| // | ||
| // var _ TracesSampler = sentry.TracesSamplers{ | ||
| // sentry.InheritFromParentSampler, | ||
| // sentry.UniformTracesSampler(0.1), | ||
| // } | ||
| // | ||
| // Another example, we can provide a sampler that returns SampledFalse if the | ||
| // SamplingContext matches some condition, and SampledUndefined otherwise: | ||
| // | ||
| // var _ TracesSampler = sentry.TracesSamplers{ | ||
| // sentry.IgnoreTransaction(regexp.MustCompile(`^\w+ /(favicon.ico|healthz)`), | ||
| // sentry.InheritFromParentSampler, | ||
| // sentry.UniformTracesSampler(0.1), | ||
| // } | ||
| // | ||
| // If after running all samplers the decision is still undefined, the | ||
| // span/transaction is not sampled. | ||
|
|
||
| // A SamplingContext is passed to a TracesSampler to determine a sampling | ||
| // decision. | ||
| // | ||
| // TODO(tracing): possibly expand SamplingContext to include custom / | ||
| // user-provided data. | ||
| type SamplingContext struct { | ||
| Span *Span // The current span, always non-nil. | ||
| Parent *Span // The parent span, may be nil. | ||
| } | ||
|
|
||
| // TODO(tracing): possibly expand SamplingContext to include custom / | ||
| // user-provided data. | ||
| // | ||
| // Unlike in other SDKs, the current http.Request is not part of the | ||
| // SamplingContext to avoid bloating it with possibly unnecessary values that | ||
| // could confuse people or have negative performance consequences. | ||
| // | ||
| // For the request to be provided in a SamplingContext, a request pointer would | ||
| // most likely need to be stored in the span context and it would open precedent | ||
| // for more arbitrary data like fasthttp.Request. | ||
| // | ||
| // Users wanting to influence the sampling decision based on the request can | ||
| // still do so, either by updating the transaction directly on their HTTP | ||
| // handler: | ||
| // | ||
| // func(w http.ResponseWriter, r *http.Request) { | ||
| // transaction := sentry.TransactionFromContext(r.Context()) | ||
| // if r.Header.Get("X-Custom-Sampling") == "yes" { | ||
| // transaction.Sampled = sentry.SampledTrue | ||
| // } else { | ||
| // transaction.Sampled = sentry.SampledFalse | ||
| // } | ||
| // } | ||
| // | ||
| // Or by having their own middleware that stores arbitrary data in the request | ||
| // context (a pointer to the request itself included): | ||
| // | ||
| // type myContextKey struct{} | ||
| // type myContextData struct { | ||
| // request *http.Request | ||
| // // ... | ||
| // } | ||
| // | ||
| // func middleware(h http.Handler) http.Handler { | ||
| // return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { | ||
| // data := &myContextData{ | ||
| // request: r, | ||
| // } | ||
| // ctx := context.WithValue(r.Context(), myContextKey{}, data) | ||
| // h.ServeHTTP(w, r.WithContext(ctx)) | ||
| // }) | ||
| // } | ||
| // | ||
| // func main() { | ||
| // err := sentry.Init(sentry.ClientOptions{ | ||
| // // A custom TracesSampler can access data from the span's context: | ||
| // TracesSampler: sentry.TracesSamplerFunc(func(ctx sentry.SamplingContext) bool { | ||
| // data, ok := ctx.Span.Context().Value(myContextKey{}).(*myContextData) | ||
| // if !ok { | ||
| // return false | ||
| // } | ||
| // return data.request.URL.Hostname() == "example.com" | ||
| // }), | ||
| // }) | ||
| // // ... | ||
| // } | ||
| // | ||
| // Note, however, that for the middleware to be effective, it would have to run | ||
| // before sentryhttp's own middleware, meaning the middleware itself is not | ||
| // instrumented to send panics to Sentry and it is not part of the timed | ||
| // transaction. | ||
| // | ||
| // If neither of those prove to be sufficient, we can consider including a | ||
| // (possibly nil) *http.Request field to SamplingContext. In that case, the SDK | ||
| // would need to track the request either in the Scope or the Span.Context. | ||
| // | ||
| // Alternatively, add a map-like type or simply a generic interface{} similar to | ||
| // the CustomSamplingContext type in the Java SDK: | ||
| // | ||
| // type SamplingContext struct { | ||
| // Span *Span // The current span, always non-nil. | ||
| // Parent *Span // The parent span, may be nil. | ||
| // CustomData interface{} | ||
| // } | ||
| // | ||
| // func CustomSamplingContext(data interface{}) SpanOption { | ||
| // return func(s *Span) { | ||
| // s.customSamplingContext = data | ||
| // } | ||
| // } | ||
| // | ||
| // func main() { | ||
| // // ... | ||
| // span := sentry.StartSpan(ctx, "op", CustomSamplingContext(data)) | ||
| // // ... | ||
| // } | ||
|
|
||
| // The TracesSamplerFunc type is an adapter to allow the use of ordinary | ||
| // The TracesSample type is an adapter to allow the use of ordinary | ||
| // functions as a TracesSampler. | ||
| type TracesSamplerFunc func(ctx SamplingContext) Sampled | ||
|
|
||
| var _ TracesSampler = TracesSamplerFunc(nil) | ||
| type TracesSampler func(ctx SamplingContext) float64 | ||
|
|
||
| func (f TracesSamplerFunc) Sample(ctx SamplingContext) Sampled { | ||
| func (f TracesSampler) Sample(ctx SamplingContext) float64 { | ||
| return f(ctx) | ||
| } | ||
|
|
||
| // UniformTracesSampler is a TracesSampler that samples root spans randomly at a | ||
| // uniform rate. | ||
| type UniformTracesSampler float64 | ||
|
|
||
| var _ TracesSampler = UniformTracesSampler(0) | ||
|
|
||
| func (s UniformTracesSampler) Sample(ctx SamplingContext) Sampled { | ||
| if s < 0.0 || s > 1.0 { | ||
| panic(fmt.Errorf("sampling rate out of range [0.0, 1.0]: %f", s)) | ||
| } | ||
| if randutil.Float64() < float64(s) { | ||
| return SampledTrue | ||
| } | ||
| return SampledFalse | ||
| } | ||
|
|
||
| // TODO(tracing): implement and export basic TracesSampler implementations: | ||
| // parent-based, span ID / trace ID based, etc. It should be possible to compose | ||
| // parent-based with other samplers. |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.