Ubuntu启动RQ Worker报错：时间数据格式不匹配求助

问题场景 #

在Ubuntu系统中执行rq worker启动RQ Worker时触发报错，任务已成功加入本地Redis队列，但Worker无法正常运行，系统显示0个Worker。

错误栈信息 #

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/rq/utils.py", line 169, in utcparse
    return datetime.datetime.strptime(string, _TIMESTAMP_FORMAT)
  File "/usr/lib/python3.8/_strptime.py", line 568, in _strptime_datetime
    tt, fraction, gmtoff_fraction = _strptime(data_string, format)
  File "/usr/lib/python3.8/_strptime.py", line 349, in _strptime
    raise ValueError("time data %r does not match format %r" %
ValueError: time data '' does not match format '%Y-%m-%dT%H:%M:%S.%fZ'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/rq/worker.py", line 508, in work
    result = self.dequeue_job_and_maintain_ttl(timeout)
  File "/usr/lib/python3/dist-packages/rq/worker.py", line 574, in dequeue_job_and_maintain_ttl
    result = self.queue_class.dequeue_any(self.queues, timeout,
  File "/usr/lib/python3/dist-packages/rq/queue.py", line 539, in dequeue_any
    job = job_class.fetch(job_id, connection=connection)
  File "/usr/lib/python3/dist-packages/rq/job.py", line 303, in fetch
    job.refresh()
  File "/usr/lib/python3/dist-packages/rq/job.py", line 515, in refresh
    self.restore(data)
  File "/usr/lib/python3/dist-packages/rq/job.py", line 478, in restore
    self.started_at = str_to_date(obj.get('started_at'))

相关代码 #

任务定义（hello.py） #

def add(x, y):
    return x + y

主程序（main.py） #

from flask import Flask
from redis import Redis

from hello import add
from rq import Queue

q = Queue(connection=Redis())


app = Flask(__name__)

@app.route("/")
def hello():
    q.enqueue(add, 3, 7)
    return "Task enqueued"


if __name__ == "__main__":
    app.run(debug=True)

解决方案 #

这个错误是因为Redis队列中存在损坏的任务数据——某个任务的started_at字段是空字符串，RQ解析时无法匹配时间格式导致崩溃。

解决步骤：

• 清理Redis中的损坏任务数据：
  1. 进入Redis命令行：redis-cli
  2. 查看所有RQ相关键：KEYS "rq:*"
  3. 删除相关队列和任务键，比如默认队列：DEL rq:queue:default，或具体任务ID对应的键：DEL rq:job:xxx
     （如果数据无保留价值，可直接执行FLUSHDB清空当前Redis数据库，谨慎操作）
• 重启RQ Worker：rq worker
• 重新触发任务，验证Worker运行状态

另外，旧版本RQ可能存在空时间字段处理的bug，建议升级到最新稳定版：pip install --upgrade rq

内容的提问来源于stack exchange，提问作者Gaming Fury