mirror of https://github.com/k3s-io/k3s
58 lines
1.6 KiB
Go
58 lines
1.6 KiB
Go
/*
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Copyright 2017 The Kubernetes Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package eventratelimit
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import (
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"github.com/hashicorp/golang-lru"
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"k8s.io/client-go/util/flowcontrol"
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)
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// cache is an interface for caching the limits of a particular type
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type cache interface {
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// get the rate limiter associated with the specified key
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get(key interface{}) flowcontrol.RateLimiter
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}
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// singleCache is a cache that only stores a single, constant item
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type singleCache struct {
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// the single rate limiter held by the cache
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rateLimiter flowcontrol.RateLimiter
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}
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func (c *singleCache) get(key interface{}) flowcontrol.RateLimiter {
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return c.rateLimiter
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}
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// lruCache is a least-recently-used cache
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type lruCache struct {
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// factory to use to create new rate limiters
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rateLimiterFactory func() flowcontrol.RateLimiter
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// the actual LRU cache
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cache *lru.Cache
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}
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func (c *lruCache) get(key interface{}) flowcontrol.RateLimiter {
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value, found := c.cache.Get(key)
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if !found {
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rateLimter := c.rateLimiterFactory()
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c.cache.Add(key, rateLimter)
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return rateLimter
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}
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return value.(flowcontrol.RateLimiter)
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}
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