mirror of
https://github.com/hibiken/asynq.git
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548 lines
16 KiB
Go
548 lines
16 KiB
Go
// Copyright 2020 Kentaro Hibino. All rights reserved.
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// Use of this source code is governed by a MIT license
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// that can be found in the LICENSE file.
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// Package rdb encapsulates the interactions with redis.
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package rdb
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import (
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"encoding/json"
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"errors"
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"fmt"
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"time"
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"github.com/go-redis/redis/v7"
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"github.com/hibiken/asynq/internal/base"
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"github.com/spf13/cast"
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)
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var (
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// ErrNoProcessableTask indicates that there are no tasks ready to be processed.
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ErrNoProcessableTask = errors.New("no tasks are ready for processing")
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// ErrTaskNotFound indicates that a task that matches the given identifier was not found.
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ErrTaskNotFound = errors.New("could not find a task")
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// ErrDuplicateTask indicates that another task with the same unique key holds the uniqueness lock.
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ErrDuplicateTask = errors.New("task already exists")
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)
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const statsTTL = 90 * 24 * time.Hour // 90 days
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// RDB is a client interface to query and mutate task queues.
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type RDB struct {
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client *redis.Client
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}
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// NewRDB returns a new instance of RDB.
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func NewRDB(client *redis.Client) *RDB {
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return &RDB{client}
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}
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// Close closes the connection with redis server.
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func (r *RDB) Close() error {
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return r.client.Close()
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}
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// KEYS[1] -> asynq:queues:<qname>
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// KEYS[2] -> asynq:queues
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// ARGV[1] -> task message data
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var enqueueCmd = redis.NewScript(`
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redis.call("LPUSH", KEYS[1], ARGV[1])
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redis.call("SADD", KEYS[2], KEYS[1])
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return 1`)
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// Enqueue inserts the given task to the tail of the queue.
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func (r *RDB) Enqueue(msg *base.TaskMessage) error {
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bytes, err := json.Marshal(msg)
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if err != nil {
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return err
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}
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key := base.QueueKey(msg.Queue)
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return enqueueCmd.Run(r.client, []string{key, base.AllQueues}, bytes).Err()
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}
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// KEYS[1] -> unique key in the form <type>:<payload>:<qname>
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// KEYS[2] -> asynq:queues:<qname>
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// KEYS[2] -> asynq:queues
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// ARGV[1] -> task ID
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// ARGV[2] -> uniqueness lock TTL
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// ARGV[3] -> task message data
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var enqueueUniqueCmd = redis.NewScript(`
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local ok = redis.call("SET", KEYS[1], ARGV[1], "NX", "EX", ARGV[2])
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if not ok then
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return 0
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end
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redis.call("LPUSH", KEYS[2], ARGV[3])
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redis.call("SADD", KEYS[3], KEYS[2])
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return 1
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`)
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// EnqueueUnique inserts the given task if the task's uniqueness lock can be acquired.
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// It returns ErrDuplicateTask if the lock cannot be acquired.
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func (r *RDB) EnqueueUnique(msg *base.TaskMessage, ttl time.Duration) error {
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bytes, err := json.Marshal(msg)
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if err != nil {
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return err
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}
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key := base.QueueKey(msg.Queue)
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res, err := enqueueUniqueCmd.Run(r.client,
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[]string{msg.UniqueKey, key, base.AllQueues},
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msg.ID.String(), int(ttl.Seconds()), bytes).Result()
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if err != nil {
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return err
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}
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n, ok := res.(int64)
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if !ok {
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return fmt.Errorf("could not cast %v to int64", res)
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}
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if n == 0 {
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return ErrDuplicateTask
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}
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return nil
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}
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// Dequeue queries given queues in order and pops a task message if there is one and returns it.
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// If all queues are empty, ErrNoProcessableTask error is returned.
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func (r *RDB) Dequeue(qnames ...string) (*base.TaskMessage, error) {
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var data string
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var err error
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if len(qnames) == 1 {
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data, err = r.dequeueSingle(base.QueueKey(qnames[0]))
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} else {
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var keys []string
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for _, q := range qnames {
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keys = append(keys, base.QueueKey(q))
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}
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data, err = r.dequeue(keys...)
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}
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if err == redis.Nil {
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return nil, ErrNoProcessableTask
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}
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if err != nil {
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return nil, err
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}
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var msg base.TaskMessage
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err = json.Unmarshal([]byte(data), &msg)
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if err != nil {
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return nil, err
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}
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return &msg, nil
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}
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func (r *RDB) dequeueSingle(queue string) (data string, err error) {
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// timeout needed to avoid blocking forever
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return r.client.BRPopLPush(queue, base.InProgressQueue, time.Second).Result()
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}
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// KEYS[1] -> asynq:in_progress
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// ARGV -> List of queues to query in order
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var dequeueCmd = redis.NewScript(`
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local res
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for _, qkey in ipairs(ARGV) do
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res = redis.call("RPOPLPUSH", qkey, KEYS[1])
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if res then
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return res
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end
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end
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return res`)
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func (r *RDB) dequeue(queues ...string) (data string, err error) {
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var args []interface{}
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for _, qkey := range queues {
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args = append(args, qkey)
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}
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res, err := dequeueCmd.Run(r.client, []string{base.InProgressQueue}, args...).Result()
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if err != nil {
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return "", err
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}
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return cast.ToStringE(res)
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}
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// KEYS[1] -> asynq:in_progress
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// KEYS[2] -> asynq:processed:<yyyy-mm-dd>
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// KEYS[3] -> unique key in the format <type>:<payload>:<qname>
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// ARGV[1] -> base.TaskMessage value
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// ARGV[2] -> stats expiration timestamp
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// ARGV[3] -> task ID
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// Note: LREM count ZERO means "remove all elements equal to val"
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var doneCmd = redis.NewScript(`
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redis.call("LREM", KEYS[1], 0, ARGV[1])
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local n = redis.call("INCR", KEYS[2])
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if tonumber(n) == 1 then
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redis.call("EXPIREAT", KEYS[2], ARGV[2])
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end
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if string.len(KEYS[3]) > 0 and redis.call("GET", KEYS[3]) == ARGV[3] then
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redis.call("DEL", KEYS[3])
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end
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return redis.status_reply("OK")
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`)
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// Done removes the task from in-progress queue to mark the task as done.
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// It removes a uniqueness lock acquired by the task, if any.
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func (r *RDB) Done(msg *base.TaskMessage) error {
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bytes, err := json.Marshal(msg)
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if err != nil {
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return err
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}
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now := time.Now()
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processedKey := base.ProcessedKey(now)
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expireAt := now.Add(statsTTL)
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return doneCmd.Run(r.client,
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[]string{base.InProgressQueue, processedKey, msg.UniqueKey},
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bytes, expireAt.Unix(), msg.ID.String()).Err()
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}
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// KEYS[1] -> asynq:in_progress
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// KEYS[2] -> asynq:queues:<qname>
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// ARGV[1] -> base.TaskMessage value
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// Note: Use RPUSH to push to the head of the queue.
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var requeueCmd = redis.NewScript(`
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redis.call("LREM", KEYS[1], 0, ARGV[1])
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redis.call("RPUSH", KEYS[2], ARGV[1])
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return redis.status_reply("OK")`)
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// Requeue moves the task from in-progress queue to the specified queue.
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func (r *RDB) Requeue(msg *base.TaskMessage) error {
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bytes, err := json.Marshal(msg)
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if err != nil {
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return err
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}
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return requeueCmd.Run(r.client,
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[]string{base.InProgressQueue, base.QueueKey(msg.Queue)},
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string(bytes)).Err()
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}
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// KEYS[1] -> asynq:scheduled
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// KEYS[2] -> asynq:queues
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// ARGV[1] -> score (process_at timestamp)
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// ARGV[2] -> task message
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// ARGV[3] -> queue key
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var scheduleCmd = redis.NewScript(`
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redis.call("ZADD", KEYS[1], ARGV[1], ARGV[2])
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redis.call("SADD", KEYS[2], ARGV[3])
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return 1
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`)
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// Schedule adds the task to the backlog queue to be processed in the future.
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func (r *RDB) Schedule(msg *base.TaskMessage, processAt time.Time) error {
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bytes, err := json.Marshal(msg)
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if err != nil {
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return err
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}
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qkey := base.QueueKey(msg.Queue)
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score := float64(processAt.Unix())
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return scheduleCmd.Run(r.client,
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[]string{base.ScheduledQueue, base.AllQueues},
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score, bytes, qkey).Err()
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}
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// KEYS[1] -> unique key in the format <type>:<payload>:<qname>
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// KEYS[2] -> asynq:scheduled
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// KEYS[3] -> asynq:queues
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// ARGV[1] -> task ID
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// ARGV[2] -> uniqueness lock TTL
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// ARGV[3] -> score (process_at timestamp)
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// ARGV[4] -> task message
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// ARGV[5] -> queue key
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var scheduleUniqueCmd = redis.NewScript(`
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local ok = redis.call("SET", KEYS[1], ARGV[1], "NX", "EX", ARGV[2])
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if not ok then
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return 0
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end
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redis.call("ZADD", KEYS[2], ARGV[3], ARGV[4])
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redis.call("SADD", KEYS[3], ARGV[5])
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return 1
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`)
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// ScheduleUnique adds the task to the backlog queue to be processed in the future if the uniqueness lock can be acquired.
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// It returns ErrDuplicateTask if the lock cannot be acquired.
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func (r *RDB) ScheduleUnique(msg *base.TaskMessage, processAt time.Time, ttl time.Duration) error {
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bytes, err := json.Marshal(msg)
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if err != nil {
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return err
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}
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qkey := base.QueueKey(msg.Queue)
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score := float64(processAt.Unix())
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res, err := scheduleUniqueCmd.Run(r.client,
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[]string{msg.UniqueKey, base.ScheduledQueue, base.AllQueues},
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msg.ID.String(), int(ttl.Seconds()), score, bytes, qkey).Result()
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if err != nil {
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return err
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}
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n, ok := res.(int64)
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if !ok {
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return fmt.Errorf("could not cast %v to int64", res)
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}
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if n == 0 {
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return ErrDuplicateTask
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}
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return nil
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}
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// KEYS[1] -> asynq:in_progress
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// KEYS[2] -> asynq:retry
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// KEYS[3] -> asynq:processed:<yyyy-mm-dd>
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// KEYS[4] -> asynq:failure:<yyyy-mm-dd>
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// ARGV[1] -> base.TaskMessage value to remove from base.InProgressQueue queue
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// ARGV[2] -> base.TaskMessage value to add to Retry queue
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// ARGV[3] -> retry_at UNIX timestamp
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// ARGV[4] -> stats expiration timestamp
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var retryCmd = redis.NewScript(`
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redis.call("LREM", KEYS[1], 0, ARGV[1])
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redis.call("ZADD", KEYS[2], ARGV[3], ARGV[2])
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local n = redis.call("INCR", KEYS[3])
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if tonumber(n) == 1 then
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redis.call("EXPIREAT", KEYS[3], ARGV[4])
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end
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local m = redis.call("INCR", KEYS[4])
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if tonumber(m) == 1 then
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redis.call("EXPIREAT", KEYS[4], ARGV[4])
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end
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return redis.status_reply("OK")`)
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// Retry moves the task from in-progress to retry queue, incrementing retry count
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// and assigning error message to the task message.
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func (r *RDB) Retry(msg *base.TaskMessage, processAt time.Time, errMsg string) error {
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bytesToRemove, err := json.Marshal(msg)
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if err != nil {
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return err
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}
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modified := *msg
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modified.Retried++
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modified.ErrorMsg = errMsg
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bytesToAdd, err := json.Marshal(&modified)
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if err != nil {
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return err
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}
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now := time.Now()
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processedKey := base.ProcessedKey(now)
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failureKey := base.FailureKey(now)
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expireAt := now.Add(statsTTL)
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return retryCmd.Run(r.client,
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[]string{base.InProgressQueue, base.RetryQueue, processedKey, failureKey},
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string(bytesToRemove), string(bytesToAdd), processAt.Unix(), expireAt.Unix()).Err()
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}
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const (
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maxDeadTasks = 10000
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deadExpirationInDays = 90
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)
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// KEYS[1] -> asynq:in_progress
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// KEYS[2] -> asynq:dead
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// KEYS[3] -> asynq:processed:<yyyy-mm-dd>
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// KEYS[4] -> asynq.failure:<yyyy-mm-dd>
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// ARGV[1] -> base.TaskMessage value to remove from base.InProgressQueue queue
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// ARGV[2] -> base.TaskMessage value to add to Dead queue
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// ARGV[3] -> died_at UNIX timestamp
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// ARGV[4] -> cutoff timestamp (e.g., 90 days ago)
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// ARGV[5] -> max number of tasks in dead queue (e.g., 100)
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// ARGV[6] -> stats expiration timestamp
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var killCmd = redis.NewScript(`
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redis.call("LREM", KEYS[1], 0, ARGV[1])
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redis.call("ZADD", KEYS[2], ARGV[3], ARGV[2])
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redis.call("ZREMRANGEBYSCORE", KEYS[2], "-inf", ARGV[4])
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redis.call("ZREMRANGEBYRANK", KEYS[2], 0, -ARGV[5])
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local n = redis.call("INCR", KEYS[3])
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if tonumber(n) == 1 then
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redis.call("EXPIREAT", KEYS[3], ARGV[6])
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end
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local m = redis.call("INCR", KEYS[4])
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if tonumber(m) == 1 then
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redis.call("EXPIREAT", KEYS[4], ARGV[6])
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end
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return redis.status_reply("OK")`)
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// Kill sends the task to "dead" queue from in-progress queue, assigning
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// the error message to the task.
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// It also trims the set by timestamp and set size.
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func (r *RDB) Kill(msg *base.TaskMessage, errMsg string) error {
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bytesToRemove, err := json.Marshal(msg)
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if err != nil {
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return err
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}
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modified := *msg
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modified.ErrorMsg = errMsg
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bytesToAdd, err := json.Marshal(&modified)
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if err != nil {
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return err
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}
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now := time.Now()
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limit := now.AddDate(0, 0, -deadExpirationInDays).Unix() // 90 days ago
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processedKey := base.ProcessedKey(now)
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failureKey := base.FailureKey(now)
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expireAt := now.Add(statsTTL)
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return killCmd.Run(r.client,
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[]string{base.InProgressQueue, base.DeadQueue, processedKey, failureKey},
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string(bytesToRemove), string(bytesToAdd), now.Unix(), limit, maxDeadTasks, expireAt.Unix()).Err()
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}
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// KEYS[1] -> asynq:in_progress
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// ARGV[1] -> queue prefix
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var requeueAllCmd = redis.NewScript(`
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local msgs = redis.call("LRANGE", KEYS[1], 0, -1)
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for _, msg in ipairs(msgs) do
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local decoded = cjson.decode(msg)
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local qkey = ARGV[1] .. decoded["Queue"]
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redis.call("RPUSH", qkey, msg)
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redis.call("LREM", KEYS[1], 0, msg)
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end
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return table.getn(msgs)`)
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// RequeueAll moves all tasks from in-progress list to the queue
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// and reports the number of tasks restored.
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func (r *RDB) RequeueAll() (int64, error) {
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res, err := requeueAllCmd.Run(r.client, []string{base.InProgressQueue}, base.QueuePrefix).Result()
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if err != nil {
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return 0, err
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}
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n, ok := res.(int64)
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if !ok {
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return 0, fmt.Errorf("could not cast %v to int64", res)
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}
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return n, nil
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}
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// CheckAndEnqueue checks for all scheduled tasks and enqueues any tasks that
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// have to be processed.
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//
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// qnames specifies to which queues to send tasks.
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func (r *RDB) CheckAndEnqueue(qnames ...string) error {
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delayed := []string{base.ScheduledQueue, base.RetryQueue}
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for _, zset := range delayed {
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var err error
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if len(qnames) == 1 {
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err = r.forwardSingle(zset, base.QueueKey(qnames[0]))
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} else {
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err = r.forward(zset)
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}
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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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}
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// KEYS[1] -> source queue (e.g. scheduled or retry queue)
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// ARGV[1] -> current unix time
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// ARGV[2] -> queue prefix
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var forwardCmd = redis.NewScript(`
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local msgs = redis.call("ZRANGEBYSCORE", KEYS[1], "-inf", ARGV[1])
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for _, msg in ipairs(msgs) do
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local decoded = cjson.decode(msg)
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local qkey = ARGV[2] .. decoded["Queue"]
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redis.call("LPUSH", qkey, msg)
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redis.call("ZREM", KEYS[1], msg)
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end
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return msgs`)
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// forward moves all tasks with a score less than the current unix time
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// from the src zset.
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func (r *RDB) forward(src string) error {
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now := float64(time.Now().Unix())
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return forwardCmd.Run(r.client,
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[]string{src}, now, base.QueuePrefix).Err()
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}
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// KEYS[1] -> source queue (e.g. scheduled or retry queue)
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// KEYS[2] -> destination queue
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var forwardSingleCmd = redis.NewScript(`
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local msgs = redis.call("ZRANGEBYSCORE", KEYS[1], "-inf", ARGV[1])
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for _, msg in ipairs(msgs) do
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redis.call("LPUSH", KEYS[2], msg)
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redis.call("ZREM", KEYS[1], msg)
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end
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return msgs`)
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// forwardSingle moves all tasks with a score less than the current unix time
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// from the src zset to dst list.
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func (r *RDB) forwardSingle(src, dst string) error {
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now := float64(time.Now().Unix())
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return forwardSingleCmd.Run(r.client,
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[]string{src, dst}, now).Err()
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}
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// KEYS[1] -> asynq:servers:<host:pid:sid>
|
|
// KEYS[2] -> asynq:servers
|
|
// KEYS[3] -> asynq:workers<host:pid:sid>
|
|
// keys[4] -> asynq:workers
|
|
// ARGV[1] -> expiration time
|
|
// ARGV[2] -> TTL in seconds
|
|
// ARGV[3] -> process info
|
|
// ARGV[4:] -> alternate key-value pair of (worker id, worker data)
|
|
// Note: Add key to ZSET with expiration time as score.
|
|
// ref: https://github.com/antirez/redis/issues/135#issuecomment-2361996
|
|
var writeProcessInfoCmd = redis.NewScript(`
|
|
redis.call("SETEX", KEYS[1], ARGV[2], ARGV[3])
|
|
redis.call("ZADD", KEYS[2], ARGV[1], KEYS[1])
|
|
redis.call("DEL", KEYS[3])
|
|
for i = 4, table.getn(ARGV)-1, 2 do
|
|
redis.call("HSET", KEYS[3], ARGV[i], ARGV[i+1])
|
|
end
|
|
redis.call("EXPIRE", KEYS[3], ARGV[2])
|
|
redis.call("ZADD", KEYS[4], ARGV[1], KEYS[3])
|
|
return redis.status_reply("OK")`)
|
|
|
|
// WriteServerState writes server state data to redis with expiration set to the value ttl.
|
|
func (r *RDB) WriteServerState(ss *base.ServerState, ttl time.Duration) error {
|
|
info := ss.GetInfo()
|
|
bytes, err := json.Marshal(info)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
var args []interface{} // args to the lua script
|
|
exp := time.Now().Add(ttl).UTC()
|
|
workers := ss.GetWorkers()
|
|
args = append(args, float64(exp.Unix()), ttl.Seconds(), bytes)
|
|
for _, w := range workers {
|
|
bytes, err := json.Marshal(w)
|
|
if err != nil {
|
|
continue // skip bad data
|
|
}
|
|
args = append(args, w.ID.String(), bytes)
|
|
}
|
|
skey := base.ServerInfoKey(info.Host, info.PID, info.ServerID)
|
|
wkey := base.WorkersKey(info.Host, info.PID, info.ServerID)
|
|
return writeProcessInfoCmd.Run(r.client,
|
|
[]string{skey, base.AllServers, wkey, base.AllWorkers},
|
|
args...).Err()
|
|
}
|
|
|
|
// KEYS[1] -> asynq:servers
|
|
// KEYS[2] -> asynq:servers:<host:pid:sid>
|
|
// KEYS[3] -> asynq:workers
|
|
// KEYS[4] -> asynq:workers<host:pid:sid>
|
|
var clearProcessInfoCmd = redis.NewScript(`
|
|
redis.call("ZREM", KEYS[1], KEYS[2])
|
|
redis.call("DEL", KEYS[2])
|
|
redis.call("ZREM", KEYS[3], KEYS[4])
|
|
redis.call("DEL", KEYS[4])
|
|
return redis.status_reply("OK")`)
|
|
|
|
// ClearServerState deletes server state data from redis.
|
|
func (r *RDB) ClearServerState(ss *base.ServerState) error {
|
|
info := ss.GetInfo()
|
|
host, pid, id := info.Host, info.PID, info.ServerID
|
|
skey := base.ServerInfoKey(host, pid, id)
|
|
wkey := base.WorkersKey(host, pid, id)
|
|
return clearProcessInfoCmd.Run(r.client,
|
|
[]string{base.AllServers, skey, base.AllWorkers, wkey}).Err()
|
|
}
|
|
|
|
// CancelationPubSub returns a pubsub for cancelation messages.
|
|
func (r *RDB) CancelationPubSub() (*redis.PubSub, error) {
|
|
pubsub := r.client.Subscribe(base.CancelChannel)
|
|
_, err := pubsub.Receive()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return pubsub, nil
|
|
}
|
|
|
|
// PublishCancelation publish cancelation message to all subscribers.
|
|
// The message is the ID for the task to be canceled.
|
|
func (r *RDB) PublishCancelation(id string) error {
|
|
return r.client.Publish(base.CancelChannel, id).Err()
|
|
}
|