mirror of https://github.com/yunginnanet/Rate5
66 lines
1.9 KiB
Go
66 lines
1.9 KiB
Go
package rate5
|
|
|
|
import (
|
|
"fmt"
|
|
"sync"
|
|
|
|
"github.com/patrickmn/go-cache"
|
|
)
|
|
|
|
const (
|
|
// DefaultWindow is the standard window of time ratelimit triggers are observed in seconds.
|
|
DefaultWindow = 25
|
|
// DefaultBurst is the standard amount of triggers observed within Window before ratelimiting occurs.
|
|
DefaultBurst = 25
|
|
)
|
|
|
|
// Identity is an interface that allows any arbitrary type to be used for a unique key in ratelimit checks when implemented.
|
|
type Identity interface {
|
|
UniqueKey() string
|
|
}
|
|
|
|
// IdentityStringer is an implentation of Identity that acts as a shim for types that implement fmt.Stringer.
|
|
type IdentityStringer struct {
|
|
stringer fmt.Stringer
|
|
}
|
|
|
|
func (i IdentityStringer) UniqueKey() string {
|
|
return i.stringer.String()
|
|
}
|
|
|
|
const (
|
|
DebugDisabled uint32 = iota
|
|
DebugEnabled
|
|
)
|
|
|
|
// Limiter implements an Enforcer to create an arbitrary ratelimiter.
|
|
type Limiter struct {
|
|
// Patrons gives access to the underlying cache type that powers the ratelimiter.
|
|
// It is exposed for testing purposes.
|
|
Patrons *cache.Cache
|
|
|
|
// Ruleset determines the Policy which is used to determine whether or not to ratelimit.
|
|
// It consists of a Window and Burst, see Policy for more details.
|
|
Ruleset Policy
|
|
|
|
debug uint32
|
|
debugChannel chan string
|
|
debugLost int64
|
|
known map[interface{}]*int64
|
|
debugMutex *sync.RWMutex
|
|
*sync.RWMutex
|
|
}
|
|
|
|
// Policy defines the mechanics of our ratelimiter.
|
|
type Policy struct {
|
|
// Window defines the duration in seconds that we should keep track of ratelimit triggers,
|
|
Window int64
|
|
// Burst is the amount of times that Check will not trigger a limit within the duration defined by Window.
|
|
Burst int64
|
|
// Strict mode punishes triggers of the ratelimitter by increasing the wait time upon every trigger of the limiter.
|
|
Strict bool
|
|
// Hardcore mode implies strict mode but instead of using addition when adding to the wait time, it uses multiplication.
|
|
// This will cause exponential ratelimiting.
|
|
Hardcore bool
|
|
}
|