100 lines
1.6 KiB
Go
100 lines
1.6 KiB
Go
package cache
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import (
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"github.com/go-redis/redis/v7"
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"github.com/miekg/dns"
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"meow.tf/joker/godns/settings"
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"time"
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)
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func NewRedisCache(c settings.RedisSettings, expire time.Duration) *RedisCache {
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rc := redis.NewClient(&redis.Options{Addr: c.Addr(), DB: c.DB, Password: c.Password})
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return &RedisCache{
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backend: rc,
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expire: expire,
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}
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}
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type RedisCache struct {
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Cache
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backend *redis.Client
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expire time.Duration
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}
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func (m *RedisCache) Set(key string, msg *dns.Msg) error {
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var val []byte
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var err error
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key = "cache:" + key
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// handle cases for negacache where it sets nil values
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if msg == nil {
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val = []byte("nil")
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} else {
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val, err = msg.Pack()
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}
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if err != nil {
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err = SerializerError{err}
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}
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return m.backend.Set(key, val, m.expire).Err()
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}
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func (m *RedisCache) Get(key string) (*dns.Msg, error) {
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var msg dns.Msg
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var err error
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key = "cache:" + key
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item, err := m.backend.Get(key).Bytes()
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if err != nil {
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err = KeyNotFound{key}
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return &msg, err
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}
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err = msg.Unpack(item)
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if err != nil {
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err = SerializerError{err}
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}
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return &msg, err
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}
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func (m *RedisCache) Exists(key string) bool {
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res, err := m.backend.Exists(key).Result()
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if err != nil {
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return true
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}
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return res == 1
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}
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func (m *RedisCache) Remove(key string) error {
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return m.backend.Del(key).Err()
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}
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func (m *RedisCache) Full() bool {
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// redis is never full (LRU)
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return false
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}
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func (m *RedisCache) Purge() error {
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iter := m.backend.Scan(0, "cache:*", 0).Iterator()
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if iter.Err() != nil {
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return iter.Err()
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}
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var err error
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for iter.Next() {
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err = m.backend.Del(iter.Val()).Err()
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if err != nil {
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return err
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}
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}
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return nil
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} |