/
holder.go
64 lines (49 loc) · 1.2 KB
/
holder.go
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package container
import (
"context"
"fmt"
"sync"
)
type ctxHolder struct{}
var ctxHolderKey = &ctxHolder{}
type holder struct {
currentlyInCreation map[string]struct{}
mu sync.RWMutex
}
func newHolder() *holder {
return &holder{
currentlyInCreation: map[string]struct{}{},
}
}
func (h *holder) isCurrentlyInCreation(name string) bool {
defer h.mu.Unlock()
h.mu.Lock()
if _, ok := h.currentlyInCreation[name]; ok {
return true
}
return false
}
func (h *holder) beforeCreation(name string) error {
defer h.mu.Unlock()
h.mu.Lock()
if _, ok := h.currentlyInCreation[name]; ok {
return fmt.Errorf("container: instance with name %s is currently in creation, maybe it has got circular dependency cycle", name)
}
h.currentlyInCreation[name] = struct{}{}
return nil
}
func (h *holder) afterCreation(name string) {
defer h.mu.Unlock()
h.mu.Lock()
delete(h.currentlyInCreation, name)
}
func holderFromContext(ctx context.Context) *holder {
return ctx.Value(ctxHolderKey).(*holder)
}
func contextWithHolder(parent context.Context) context.Context {
h := parent.Value(ctxHolderKey)
if h != nil {
return parent
}
return context.WithValue(parent, ctxHolderKey, newHolder())
}