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Build & Publish Docker Image / build-and-push (push) Failing after 11s
63 lines
1.8 KiB
Go
63 lines
1.8 KiB
Go
package middleware
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import (
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"fmt"
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"log"
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"net/http"
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"strings"
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"time"
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"emly-api-go/internal/timing"
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)
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// Timing is a middleware that measures per-request step durations.
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//
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// It injects a *timing.Timer into the request context so that handlers can
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// record named checkpoints with timing.Mark(r.Context(), "step_name").
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// After the handler returns, it logs a single line of the form:
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//
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// [TIMING] METHOD /path step1=1.2ms step2=18ms total=20ms
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//
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// Each step duration is measured from the previous checkpoint (or request
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// start for the first one), so the values add up to the total.
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func Timing(next http.Handler) http.Handler {
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return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
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ctx, t := timing.NewContext(r.Context())
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next.ServeHTTP(w, r.WithContext(ctx))
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total := time.Since(t.Start)
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checkpoints := t.Checkpoints()
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if len(checkpoints) == 0 {
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// No checkpoints: just log the total so every request is visible.
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log.Printf("[TIMING] %s %s total=%s", r.Method, r.URL.Path, round(total))
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return
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}
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parts := make([]string, 0, len(checkpoints)+1)
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prev := t.Start
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for _, cp := range checkpoints {
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parts = append(parts, fmt.Sprintf("%s=%s", cp.Name, round(cp.At.Sub(prev))))
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prev = cp.At
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}
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// Remainder after the last checkpoint.
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if tail := total - prev.Sub(t.Start); tail > 0 {
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parts = append(parts, fmt.Sprintf("response=%s", round(tail)))
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}
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parts = append(parts, fmt.Sprintf("total=%s", round(total)))
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log.Printf("[TIMING] %s %s %s", r.Method, r.URL.Path, strings.Join(parts, " "))
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})
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}
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func round(d time.Duration) string {
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switch {
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case d < time.Microsecond:
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return fmt.Sprintf("%dns", d.Nanoseconds())
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case d < time.Millisecond:
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return fmt.Sprintf("%.2fµs", float64(d.Nanoseconds())/1e3)
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default:
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return fmt.Sprintf("%.2fms", float64(d.Nanoseconds())/1e6)
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}
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}
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