92 lines
1.8 KiB
Go
92 lines
1.8 KiB
Go
/*
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Copyright 2024 Adora Laura Kalb <adora@lila.network>
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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 cache
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import (
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"net/netip"
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"sync"
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"time"
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)
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var (
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GlobalScoreCache *ScoreCache
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cacheExpiredAfter = 5 * time.Minute
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)
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type ServerScore struct {
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expiresAt time.Time
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Score float64
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}
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type ScoreCache struct {
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stop chan struct{}
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mu sync.RWMutex
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scores map[netip.Addr]ServerScore
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}
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type CacheMissError struct{}
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func (m *CacheMissError) Error() string {
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return "User is not in cache!"
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}
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func newCacheMissError() *CacheMissError {
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return &CacheMissError{}
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}
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func NewLocalCache() *ScoreCache {
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lc := &ScoreCache{
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scores: make(map[netip.Addr]ServerScore),
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stop: make(chan struct{}),
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}
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return lc
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}
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func (sc *ScoreCache) Add(score float64, ip netip.Addr, ts time.Time) {
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ssc := ServerScore{Score: score, expiresAt: ts.Add(cacheExpiredAfter)}
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sc.mu.Lock()
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sc.scores[ip] = ssc
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sc.mu.Unlock()
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}
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func (lc *ScoreCache) Get(ip netip.Addr) (ServerScore, error) {
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now := time.Now()
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lc.mu.RLock()
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defer lc.mu.RUnlock()
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cachedScore, ok := lc.scores[ip]
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if !ok {
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return ServerScore{}, newCacheMissError()
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}
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if now.After(cachedScore.expiresAt) {
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lc.delete(ip)
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return ServerScore{}, newCacheMissError()
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}
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return cachedScore, nil
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}
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func (lc *ScoreCache) delete(ip netip.Addr) {
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lc.mu.Lock()
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delete(lc.scores, ip)
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lc.mu.Unlock()
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}
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