fix go mod issue based on Custom checker for half-open state like ReadyToTrip branch

README.md

@@ -2,14 +2,16 @@ gobreaker
 =========
 
 [![GoDoc](https://godoc.org/github.com/sony/gobreaker?status.svg)](http://godoc.org/github.com/sony/gobreaker)
+[![Build Status](https://travis-ci.org/sony/gobreaker.svg?branch=master)](https://travis-ci.org/sony/gobreaker)
+[![Coverage Status](https://coveralls.io/repos/sony/gobreaker/badge.svg?branch=master&service=github)](https://coveralls.io/github/sony/gobreaker?branch=master)
 
 [gobreaker][repo-url] implements the [Circuit Breaker pattern](https://msdn.microsoft.com/en-us/library/dn589784.aspx) in Go.
 
 Installation
 ------------
 
 ```
-go get github.com/sony/gobreaker
+go get github.com/rocyou/gobreaker
 ```
 
 Usage
@@ -27,20 +29,21 @@ You can configure `CircuitBreaker` by the struct `Settings`:
 ```go
 type Settings struct {
 	Name          string
-	MaxRequests   uint32
+	ReadyToClose  func(counts Counts) (bool, bool)
 	Interval      time.Duration
 	Timeout       time.Duration
 	ReadyToTrip   func(counts Counts) bool
 	OnStateChange func(name string, from State, to State)
-	IsSuccessful  func(err error) bool
 }
 ```
 
 - `Name` is the name of the `CircuitBreaker`.
 
-- `MaxRequests` is the maximum number of requests allowed to pass through
-  when the `CircuitBreaker` is half-open.
-  If `MaxRequests` is 0, `CircuitBreaker` allows only 1 request.
+- `ReadyToClose` is called with a copy of `Counts` for each request in the half-open state.
+  If `ReadyToClose` returns true, the `CircuitBreaker` will be placed into the close state.
+  If `ReadyToClose` returns false, the `CircuitBreaker` will be placed into the open state if second returned value is true.
+  If `ReadyToClose` is nil, default `ReadyToClose` is used.
+  Default `ReadyToClose` returns true when the number of consecutive successes is more than 1.
 
 - `Interval` is the cyclic period of the closed state
   for `CircuitBreaker` to clear the internal `Counts`, described later in this section.
@@ -57,11 +60,6 @@ type Settings struct {
 
 - `OnStateChange` is called whenever the state of `CircuitBreaker` changes.
 
-- `IsSuccessful` is called with the error returned from a request.
-  If `IsSuccessful` returns true, the error is counted as a success.
-  Otherwise the error is counted as a failure.
-  If `IsSuccessful` is nil, default `IsSuccessful` is used, which returns false for all non-nil errors.
-
 The struct `Counts` holds the numbers of requests and their successes/failures:
 
 ```go

example/http_breaker.go

@@ -5,8 +5,9 @@ import (
 	"io/ioutil"
 	"log"
 	"net/http"
+	"time"
 
-	"github.com/sony/gobreaker"
+	"github.com/rocyou/gobreaker"
 )
 
 var cb *gobreaker.CircuitBreaker
@@ -15,10 +16,24 @@ func init() {
 	var st gobreaker.Settings
 	st.Name = "HTTP GET"
 	st.ReadyToTrip = func(counts gobreaker.Counts) bool {
-		failureRatio := float64(counts.TotalFailures) / float64(counts.Requests)
-		return counts.Requests >= 3 && failureRatio >= 0.6
+		return counts.ConsecutiveFailures >= 3
+	}
+	st.Interval = time.Duration(0) * time.Second
+	st.Timeout = time.Duration(3) * time.Second
+	st.ReadyToClose = func(counts gobreaker.Counts) (bool, bool) {
+		if counts.TotalSuccesses >= 2 {
+			return true, true
+		}
+		var nowOpen bool
+		if counts.ConsecutiveFailures >= 3 {
+			nowOpen = true
+		}
+		return false, nowOpen
+	}
+	st.OnStateChange = func(name string, from gobreaker.State, to gobreaker.State) {
+		fmt.Printf("change state from:%+v to:%+v\n", from, to)
+		//implement your action here
 	}
-
 	cb = gobreaker.NewCircuitBreaker(st)
 }
 
@@ -29,19 +44,16 @@ func Get(url string) ([]byte, error) {
 		if err != nil {
 			return nil, err
 		}
-
 		defer resp.Body.Close()
 		body, err := ioutil.ReadAll(resp.Body)
 		if err != nil {
 			return nil, err
 		}
-
 		return body, nil
 	})
 	if err != nil {
 		return nil, err
 	}
-
 	return body.([]byte), nil
 }
 

go.mod

@@ -1,5 +1,5 @@
-module github.com/sony/gobreaker
+module github.com/rocyou/gobreaker
 
-go 1.12
+go 1.16
 
-require github.com/stretchr/testify v1.3.0
+require github.com/stretchr/testify v1.7.0

go.sum

@@ -3,5 +3,9 @@ github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
-github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

gobreaker.go

@@ -20,8 +20,6 @@ const (
 )
 
 var (
-	// ErrTooManyRequests is returned when the CB state is half open and the requests count is over the cb maxRequests
-	ErrTooManyRequests = errors.New("too many requests")
 	// ErrOpenState is returned when the CB state is open
 	ErrOpenState = errors.New("circuit breaker is open")
 )
@@ -80,9 +78,11 @@ func (c *Counts) clear() {
 //
 // Name is the name of the CircuitBreaker.
 //
-// MaxRequests is the maximum number of requests allowed to pass through
-// when the CircuitBreaker is half-open.
-// If MaxRequests is 0, the CircuitBreaker allows only 1 request.
+// ReadyToClose is called with a copy of Counts for each request in the half-open state.
+// If ReadyToClose returns true, the CircuitBreaker will be placed into the close state.
+// If ReadyToClose returns false, the CircuitBreaker will be placed into the open state if second returned value is true.
+// If ReadyToClose is nil, default ReadyToClose is used.
+// Default ReadyToClose returns true when the number of consecutive successes is more than 1.
 //
 // Interval is the cyclic period of the closed state
 // for the CircuitBreaker to clear the internal Counts.
@@ -98,29 +98,22 @@ func (c *Counts) clear() {
 // Default ReadyToTrip returns true when the number of consecutive failures is more than 5.
 //
 // OnStateChange is called whenever the state of the CircuitBreaker changes.
-//
-// IsSuccessful is called with the error returned from a request.
-// If IsSuccessful returns true, the error is counted as a success.
-// Otherwise the error is counted as a failure.
-// If IsSuccessful is nil, default IsSuccessful is used, which returns false for all non-nil errors.
 type Settings struct {
 	Name          string
-	MaxRequests   uint32
+	ReadyToClose  func(counts Counts) (bool, bool)
 	Interval      time.Duration
 	Timeout       time.Duration
 	ReadyToTrip   func(counts Counts) bool
 	OnStateChange func(name string, from State, to State)
-	IsSuccessful  func(err error) bool
 }
 
 // CircuitBreaker is a state machine to prevent sending requests that are likely to fail.
 type CircuitBreaker struct {
 	name          string
-	maxRequests   uint32
+	readyToClose  func(counts Counts) (bool, bool)
 	interval      time.Duration
 	timeout       time.Duration
 	readyToTrip   func(counts Counts) bool
-	isSuccessful  func(err error) bool
 	onStateChange func(name string, from State, to State)
 
 	mutex      sync.Mutex
@@ -144,10 +137,10 @@ func NewCircuitBreaker(st Settings) *CircuitBreaker {
 	cb.name = st.Name
 	cb.onStateChange = st.OnStateChange
 
-	if st.MaxRequests == 0 {
-		cb.maxRequests = 1
+	if st.ReadyToClose == nil {
+		cb.readyToClose = defaultReadyToClose
 	} else {
-		cb.maxRequests = st.MaxRequests
+		cb.readyToClose = st.ReadyToClose
 	}
 
 	if st.Interval <= 0 {
@@ -168,12 +161,6 @@ func NewCircuitBreaker(st Settings) *CircuitBreaker {
 		cb.readyToTrip = st.ReadyToTrip
 	}
 
-	if st.IsSuccessful == nil {
-		cb.isSuccessful = defaultIsSuccessful
-	} else {
-		cb.isSuccessful = st.IsSuccessful
-	}
-
 	cb.toNewGeneration(time.Now())
 
 	return cb
@@ -193,8 +180,8 @@ func defaultReadyToTrip(counts Counts) bool {
 	return counts.ConsecutiveFailures > 5
 }
 
-func defaultIsSuccessful(err error) bool {
-	return err == nil
+func defaultReadyToClose(counts Counts) (bool, bool) {
+	return counts.ConsecutiveSuccesses >= 1, true
 }
 
 // Name returns the name of the CircuitBreaker.
@@ -212,14 +199,6 @@ func (cb *CircuitBreaker) State() State {
 	return state
 }
 
-// Counts returns internal counters
-func (cb *CircuitBreaker) Counts() Counts {
-	cb.mutex.Lock()
-	defer cb.mutex.Unlock()
-
-	return cb.counts
-}
-
 // Execute runs the given request if the CircuitBreaker accepts it.
 // Execute returns an error instantly if the CircuitBreaker rejects the request.
 // Otherwise, Execute returns the result of the request.
@@ -240,7 +219,7 @@ func (cb *CircuitBreaker) Execute(req func() (interface{}, error)) (interface{},
 	}()
 
 	result, err := req()
-	cb.afterRequest(generation, cb.isSuccessful(err))
+	cb.afterRequest(generation, err == nil)
 	return result, err
 }
 
@@ -254,11 +233,6 @@ func (tscb *TwoStepCircuitBreaker) State() State {
 	return tscb.cb.State()
 }
 
-// Counts returns internal counters
-func (tscb *TwoStepCircuitBreaker) Counts() Counts {
-	return tscb.cb.Counts()
-}
-
 // Allow checks if a new request can proceed. It returns a callback that should be used to
 // register the success or failure in a separate step. If the circuit breaker doesn't allow
 // requests, it returns an error.
@@ -282,8 +256,6 @@ func (cb *CircuitBreaker) beforeRequest() (uint64, error) {
 
 	if state == StateOpen {
 		return generation, ErrOpenState
-	} else if state == StateHalfOpen && cb.counts.Requests >= cb.maxRequests {
-		return generation, ErrTooManyRequests
 	}
 
 	cb.counts.onRequest()
@@ -313,7 +285,7 @@ func (cb *CircuitBreaker) onSuccess(state State, now time.Time) {
 		cb.counts.onSuccess()
 	case StateHalfOpen:
 		cb.counts.onSuccess()
-		if cb.counts.ConsecutiveSuccesses >= cb.maxRequests {
+		if ok, _ := cb.readyToClose(cb.counts); ok {
 			cb.setState(StateClosed, now)
 		}
 	}
@@ -326,8 +298,13 @@ func (cb *CircuitBreaker) onFailure(state State, now time.Time) {
 		if cb.readyToTrip(cb.counts) {
 			cb.setState(StateOpen, now)
 		}
+
 	case StateHalfOpen:
-		cb.setState(StateOpen, now)
+		cb.counts.onFailure()
+		ok, nowOpen := cb.readyToClose(cb.counts)
+		if !ok && nowOpen {
+			cb.setState(StateOpen, now)
+		}
 	}
 }
 
@@ -337,11 +314,13 @@ func (cb *CircuitBreaker) currentState(now time.Time) (State, uint64) {
 		if !cb.expiry.IsZero() && cb.expiry.Before(now) {
 			cb.toNewGeneration(now)
 		}
+
 	case StateOpen:
 		if cb.expiry.Before(now) {
 			cb.setState(StateHalfOpen, now)
 		}
 	}
+
 	return cb.state, cb.generation
 }
 
@@ -372,8 +351,10 @@ func (cb *CircuitBreaker) toNewGeneration(now time.Time) {
 		} else {
 			cb.expiry = now.Add(cb.interval)
 		}
+
 	case StateOpen:
 		cb.expiry = now.Add(cb.timeout)
+
 	default: // StateHalfOpen
 		cb.expiry = zero
 	}