Rate5/models.go

package rate5

import (
	"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
}

// Limiter implements an Enforcer to create an arbitrary ratelimiter.
type Limiter struct {
	// Source is the implementation of the Identity interface. It is used to create a unique key for each request.
	Source Identity
	// 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        bool
	debugChannel chan string
	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
}