lotus/journal/registry.go
2020-08-26 16:09:37 +01:00

58 lines
1.3 KiB
Go

package journal
import "sync"
// EventTypeRegistry is a component that constructs tracked EventType tokens,
// for usage with a Journal.
type EventTypeRegistry interface {
// RegisterEventType introduces a new event type to a journal, and
// returns an EventType token that components can later use to check whether
// journalling for that type is enabled/suppressed, and to tag journal
// entries appropriately.
RegisterEventType(system, event string) EventType
}
// eventTypeRegistry is an embeddable mixin that takes care of tracking disabled
// event types, and returning initialized/safe EventTypes when requested.
type eventTypeRegistry struct {
sync.Mutex
m map[string]EventType
}
var _ EventTypeRegistry = (*eventTypeRegistry)(nil)
func NewEventTypeRegistry(disabled DisabledEvents) EventTypeRegistry {
ret := &eventTypeRegistry{
m: make(map[string]EventType, len(disabled)+32), // + extra capacity.
}
for _, et := range disabled {
et.enabled, et.safe = false, true
ret.m[et.System+":"+et.Event] = et
}
return ret
}
func (d *eventTypeRegistry) RegisterEventType(system, event string) EventType {
d.Lock()
defer d.Unlock()
key := system + ":" + event
if et, ok := d.m[key]; ok {
return et
}
et := EventType{
System: system,
Event: event,
enabled: true,
safe: true,
}
d.m[key] = et
return et
}