Aleksey Shakhmatov
505c7b8c4f
Implements retry middleware as a RoundTripper wrapper: - Exponential and constant backoff strategies with jitter - RFC 7231 Retry-After header parsing (seconds and HTTP-date) - Default policy retries idempotent methods on 429/5xx and network errors - Body restoration via GetBody, context cancellation, response body cleanup
57 lines
1.4 KiB
Go
57 lines
1.4 KiB
Go
package retry
|
|
|
|
import "time"
|
|
|
|
type options struct {
|
|
maxAttempts int // default 3
|
|
backoff Backoff // default ExponentialBackoff(100ms, 5s, true)
|
|
policy Policy // default: defaultPolicy (retry on 5xx and network errors)
|
|
retryAfter bool // default true, respect Retry-After header
|
|
}
|
|
|
|
// Option configures the retry transport.
|
|
type Option func(*options)
|
|
|
|
func defaults() options {
|
|
return options{
|
|
maxAttempts: 3,
|
|
backoff: ExponentialBackoff(100*time.Millisecond, 5*time.Second, true),
|
|
policy: defaultPolicy{},
|
|
retryAfter: true,
|
|
}
|
|
}
|
|
|
|
// WithMaxAttempts sets the maximum number of attempts (including the first).
|
|
// Values less than 1 are treated as 1 (no retries).
|
|
func WithMaxAttempts(n int) Option {
|
|
return func(o *options) {
|
|
if n < 1 {
|
|
n = 1
|
|
}
|
|
o.maxAttempts = n
|
|
}
|
|
}
|
|
|
|
// WithBackoff sets the backoff strategy used to compute delays between retries.
|
|
func WithBackoff(b Backoff) Option {
|
|
return func(o *options) {
|
|
o.backoff = b
|
|
}
|
|
}
|
|
|
|
// WithPolicy sets the retry policy that decides whether to retry a request.
|
|
func WithPolicy(p Policy) Option {
|
|
return func(o *options) {
|
|
o.policy = p
|
|
}
|
|
}
|
|
|
|
// WithRetryAfter controls whether the Retry-After response header is respected.
|
|
// When enabled and present, the Retry-After delay is used if it exceeds the
|
|
// backoff delay.
|
|
func WithRetryAfter(enable bool) Option {
|
|
return func(o *options) {
|
|
o.retryAfter = enable
|
|
}
|
|
}
|