71 lines
1.4 KiB
Go

package event
import (
"log/slog"
"sync"
)
const defaultChannelSize = 64
type Name string
const (
EventNameMediaServerStarted Name = "media_server_started"
)
type Event interface {
name() Name
}
// MediaServerStartedEvent is emitted when the mediaserver component starts successfully.
type MediaServerStartedEvent struct {
RTMPURL string
RTMPSURL string
}
func (e MediaServerStartedEvent) name() Name {
return "media_server_started"
}
// Bus is an event bus.
type Bus struct {
consumers map[Name][]chan Event
mu sync.Mutex
logger *slog.Logger
}
// NewBus returns a new event bus.
func NewBus(logger *slog.Logger) *Bus {
return &Bus{
consumers: make(map[Name][]chan Event),
logger: logger,
}
}
// Register registers a consumer for a given event.
func (b *Bus) Register(name Name) <-chan Event {
b.mu.Lock()
defer b.mu.Unlock()
ch := make(chan Event, defaultChannelSize)
b.consumers[name] = append(b.consumers[name], ch)
return ch
}
// Send sends an event to all registered consumers.
func (b *Bus) Send(evt Event) {
// The mutex is needed to ensure the backing array of b.consumers cannot be
// modified under our feet. There is probably a more efficient way to do this
// but this should be ok.
b.mu.Lock()
defer b.mu.Unlock()
for _, ch := range b.consumers[evt.name()] {
select {
case ch <- evt:
default:
b.logger.Warn("Event dropped", "name", evt.name())
}
}
}