Aleksey Shakhmatov
2ca930236d
Implements circuit breaker as a RoundTripper middleware: - Closed → Open after consecutive failure threshold - Open → HalfOpen after configurable duration - HalfOpen → Closed on success, back to Open on failure - Per-host tracking via sync.Map for independent endpoint isolation
51 lines
1.2 KiB
Go
51 lines
1.2 KiB
Go
package circuitbreaker
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import "time"
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type options struct {
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failureThreshold int // consecutive failures to trip
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openDuration time.Duration // how long to stay open before half-open
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halfOpenMax int // max concurrent requests in half-open
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}
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func defaults() options {
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return options{
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failureThreshold: 5,
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openDuration: 30 * time.Second,
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halfOpenMax: 1,
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}
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}
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// Option configures a Breaker.
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type Option func(*options)
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// WithFailureThreshold sets the number of consecutive failures required to
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// trip the breaker from Closed to Open. Default is 5.
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func WithFailureThreshold(n int) Option {
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return func(o *options) {
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if n > 0 {
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o.failureThreshold = n
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}
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}
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}
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// WithOpenDuration sets how long the breaker stays in the Open state before
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// transitioning to HalfOpen. Default is 30s.
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func WithOpenDuration(d time.Duration) Option {
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return func(o *options) {
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if d > 0 {
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o.openDuration = d
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}
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}
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}
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// WithHalfOpenMax sets the maximum number of concurrent probe requests
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// allowed while the breaker is in the HalfOpen state. Default is 1.
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func WithHalfOpenMax(n int) Option {
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return func(o *options) {
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if n > 0 {
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o.halfOpenMax = n
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}
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}
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}
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