Add retry stats to http retrier

errors/retrier.go

@@ -124,8 +124,21 @@ func (r Retryer[T, E]) Timeout(timeout time.Duration) Retryer[T, E] {
 	return r
 }
 
-// Do will execute the provided functions code and automatically retry using the provided retry function.
+type Stats struct {
+	// Number of failed attempts that were retryable
+	NumAttemptsRetryable uint8
+	// Number of failed attempts that were non retryable (but we retried anyway)
+	NumAttemptsNonRetryable uint8
+}
+
 func (r Retryer[T, E]) Do(ctx context.Context, fn RetryableFn[T, E]) Result[T, E] {
+	ret, _ := r.DoWithStats(ctx, fn)
+	return ret
+}
+
+// Do will execute the provided functions code and automatically retry using the provided retry function.
+func (r Retryer[T, E]) DoWithStats(ctx context.Context, fn RetryableFn[T, E]) (Result[T, E], Stats) {
+	stats := Stats{}
 	var attempt int
 	remaining := r.maxAttempts
 	for {
@@ -141,39 +154,48 @@ func (r Retryer[T, E]) Do(ctx context.Context, fn RetryableFn[T, E]) Result[T, E
 			err := result.Err()
 			isRetryable := r.isRetryableFn(ctx, err)
 			if !isRetryable && r.isEarlyReturnFn != nil && r.isEarlyReturnFn(ctx, err) {
-				return result
+				return result, stats
 			}
 
 			switch r.maxAttemptsMode {
 			case MaxAttemptsUnlimited:
 				goto RETRY
 			case MaxAttemptsNonRetryableReset:
 				if isRetryable {
+					stats.NumAttemptsRetryable++
 					remaining = r.maxAttempts
 					goto RETRY
 				} else if remaining > 0 {
+					stats.NumAttemptsNonRetryable++
 					remaining--
 				}
 			case MaxAttemptsNonRetryable:
 				if isRetryable {
+					stats.NumAttemptsRetryable++
 					goto RETRY
 				} else if remaining > 0 {
+					stats.NumAttemptsNonRetryable++
 					remaining--
 				}
 			case MaxAttempts:
+				if isRetryable {
+					stats.NumAttemptsRetryable++
+				} else {
+					stats.NumAttemptsNonRetryable++
+				}
 				if remaining > 0 {
 					remaining--
 				}
 			}
 			if remaining == 0 {
-				return result
+				return result, stats
 			}
 
 		RETRY:
 			r.bo(ctx, attempt, err)
 			attempt++
 			continue
 		}
-		return result
+		return result, stats
 	}
 }

go.mod

@@ -4,5 +4,6 @@ go 1.18
 
 require (
 	github.com/go-playground/assert/v2 v2.2.0
+	github.com/go-playground/errors/v5 v5.4.0
 	github.com/go-playground/form/v4 v4.2.1
 )

go.sum

@@ -1,5 +1,7 @@
 github.com/go-playground/assert/v2 v2.0.1/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
 github.com/go-playground/assert/v2 v2.2.0 h1:JvknZsQTYeFEAhQwI4qEt9cyV5ONwRHC+lYKSsYSR8s=
 github.com/go-playground/assert/v2 v2.2.0/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
+github.com/go-playground/errors/v5 v5.4.0 h1:BxBxwlRjuclYbRebE4ddrRrMK705lS2mHzHw7BDoDPA=
+github.com/go-playground/errors/v5 v5.4.0/go.mod h1:6aVeVHsT36RNu/m/8AvGdPv8T2J/+KfVv6Su4VvBfpQ=
 github.com/go-playground/form/v4 v4.2.1 h1:HjdRDKO0fftVMU5epjPW2SOREcZ6/wLUzEobqUGJuPw=
 github.com/go-playground/form/v4 v4.2.1/go.mod h1:q1a2BY+AQUUzhl6xA/6hBetay6dEIhMHjgvJiGo6K7U=

net/http/retrier.go

@@ -5,12 +5,12 @@ package httpext
 
 import (
 	"context"
-	"errors"
 	"io"
 	"net/http"
 	"strconv"
 	"time"
 
+	"github.com/go-playground/errors/v5"
 	bytesext "github.com/go-playground/pkg/v5/bytes"
 	errorsext "github.com/go-playground/pkg/v5/errors"
 	ioext "github.com/go-playground/pkg/v5/io"
@@ -210,13 +210,13 @@ func (r Retryer) Timeout(timeout time.Duration) Retryer {
 //
 // NOTE: it is up to the caller to close the response body if a successful request is made.
 func (r Retryer) DoResponse(ctx context.Context, fn BuildRequestFn2, expectedResponseCodes ...int) Result[*http.Response, error] {
-	return errorsext.NewRetryer[*http.Response, error]().
+	result, stats := errorsext.NewRetryer[*http.Response, error]().
 		IsRetryableFn(r.isRetryableFn).
 		MaxAttempts(r.mode, r.maxAttempts).
 		Backoff(r.backoffFn).
 		Timeout(r.timeout).
 		IsEarlyReturnFn(r.isEarlyReturnFn).
-		Do(ctx, func(ctx context.Context) Result[*http.Response, error] {
+		DoWithStats(ctx, func(ctx context.Context) Result[*http.Response, error] {
 			req := fn(ctx)
 			if req.IsErr() {
 				return Err[*http.Response, error](req.Err())
@@ -246,6 +246,10 @@ func (r Retryer) DoResponse(ctx context.Context, fn BuildRequestFn2, expectedRes
 		RETURN:
 			return Ok[*http.Response, error](resp)
 		})
+	if result.IsErr() {
+		return Err[*http.Response, error](errors.Wrapf(result.Err(), "failed with %d retryable attempts, and %d non retryable attempts", stats.NumAttemptsRetryable, stats.NumAttemptsNonRetryable))
+	}
+	return result
 }
 
 // Do will execute the provided functions code and automatically retry using the provided retry function decoding