add key circuitbreaker (#48)

* add circuitbreaker group

Author: lintanghui

circuitbreaker/group.go

@@ -0,0 +1,32 @@
+package circuitbreaker
+
+import (
+	"github.com/go-kratos/aegis/internal/syncmap"
+)
+
+// CircuitBreakerFactory 定义一个闭包类型，用于创建 CircuitBreaker 实例
+type CircuitBreakerFactory func() CircuitBreaker
+
+// Group is a circuit breaker that manages multiple circuit breakers by key.
+type Group struct {
+	requests  syncmap.SyncMap[string, CircuitBreaker]
+	cbFactory CircuitBreakerFactory
+}
+
+// NewGroupCircuitBreaker creates a new Group with the given factory.
+func NewGroup(factory CircuitBreakerFactory) *Group {
+	g := &Group{
+		cbFactory: factory,
+	}
+	return g
+}
+
+// GetCircuitBreaker returns a CircuitBreaker for the given key.
+func (g *Group) GetCircuitBreaker(key string) CircuitBreaker {
+	cb, ok := g.requests.Load(key)
+	if !ok {
+		// 使用传入的闭包创建具体的 CircuitBreaker 实例
+		cb, _ = g.requests.LoadOrStore(key, g.cbFactory())
+	}
+	return cb
+}

circuitbreaker/group_test.go

@@ -0,0 +1,33 @@
+package circuitbreaker_test
+
+import (
+	"testing"
+
+	"github.com/go-kratos/aegis/circuitbreaker"
+	"github.com/go-kratos/aegis/circuitbreaker/sre"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGroup_GetCircuitBreaker(t *testing.T) {
+	g := circuitbreaker.NewGroup(func() circuitbreaker.CircuitBreaker {
+		return sre.NewBreaker()
+	})
+	succ := g.GetCircuitBreaker("succ")
+	assert.NotNil(t, succ)
+	fail := g.GetCircuitBreaker("fail")
+	assert.NotNil(t, fail)
+	markSuccess(succ, 100)
+	markFailed(fail, 10000)
+	assert.Equal(t, succ.Allow(), nil)
+	assert.NotEqual(t, fail.Allow(), nil)
+}
+func markSuccess(cb circuitbreaker.CircuitBreaker, count int) {
+	for i := 0; i < count; i++ {
+		cb.MarkSuccess()
+	}
+}
+func markFailed(cb circuitbreaker.CircuitBreaker, count int) {
+	for i := 0; i < count; i++ {
+		cb.MarkFailed()
+	}
+}