redis/example/del-keys-without-ttl/main.go

143 lines
2.2 KiB
Go

package main
import (
"context"
"fmt"
"sync"
"github.com/go-redis/redis/v9"
)
func main() {
ctx := context.Background()
rdb := redis.NewClient(&redis.Options{
Addr: ":6379",
})
ch := make(chan string, 100)
var wg sync.WaitGroup
wg.Add(1)
go func() {
defer wg.Done()
deleted, err := process(ctx, rdb, ch)
if err != nil {
panic(err)
}
fmt.Println("deleted", deleted, "keys")
}()
iter := rdb.Scan(ctx, 0, "", 0).Iterator()
for iter.Next(ctx) {
ch <- iter.Val()
}
if err := iter.Err(); err != nil {
panic(err)
}
close(ch)
wg.Wait()
}
func process(ctx context.Context, rdb *redis.Client, in <-chan string) (int, error) {
var wg sync.WaitGroup
out := make(chan string, 100)
defer func() {
close(out)
wg.Wait()
}()
wg.Add(1)
go func() {
defer wg.Done()
if err := del(ctx, rdb, out); err != nil {
panic(err)
}
}()
var deleted int
keys := make([]string, 0, 100)
for key := range in {
keys = append(keys, key)
if len(keys) < 100 {
continue
}
var err error
keys, err = checkTTL(ctx, rdb, keys)
if err != nil {
return 0, err
}
for _, key := range keys {
out <- key
}
deleted += len(keys)
keys = keys[:0]
}
if len(keys) > 0 {
keys, err := checkTTL(ctx, rdb, keys)
if err != nil {
return 0, err
}
for _, key := range keys {
out <- key
}
deleted += len(keys)
}
return deleted, nil
}
func checkTTL(ctx context.Context, rdb *redis.Client, keys []string) ([]string, error) {
cmds, err := rdb.Pipelined(ctx, func(pipe redis.Pipeliner) error {
for _, key := range keys {
pipe.TTL(ctx, key)
}
return nil
})
if err != nil {
return nil, err
}
for i := len(cmds) - 1; i >= 0; i-- {
d, err := cmds[i].(*redis.DurationCmd).Result()
if err != nil {
return nil, err
}
if d != -1 {
keys = append(keys[:i], keys[i+1:]...)
}
}
return keys, nil
}
func del(ctx context.Context, rdb *redis.Client, in <-chan string) error {
pipe := rdb.Pipeline()
for key := range in {
pipe.Del(ctx, key)
if pipe.Len() < 100 {
continue
}
if _, err := pipe.Exec(ctx); err != nil {
return err
}
}
if _, err := pipe.Exec(ctx); err != nil {
return err
}
return nil
}