ListRedisScheduleSource do not support schedule_by_interval - schedules are stored but never executed

[BriceMichalski]

Description

When using ListRedisScheduleSource with schedule_by_interval(), the schedule data is stored in Redis (schedule:data:{id}) but the schedule is never executed because it's not added to any index list.

Root Cause

In ListRedisScheduleSource.add_schedule(), only cron and time schedules are indexed:

async def add_schedule(self, schedule: "ScheduledTask") -> None:
    async with Redis(connection_pool=self._connection_pool) as redis:
        await redis.set(
            f"{self._prefix}:data:{schedule.schedule_id}",
            self._serializer.dumpb(model_dump(schedule)),
        )
        if schedule.cron is not None:
            await redis.rpush(self._get_cron_key(), schedule.schedule_id)
        elif schedule.time is not None:
            await redis.rpush(self._get_time_key(schedule.time), schedule.schedule_id)
        # ⚠️ schedule.interval is NOT handled - data is saved but never indexed

Similarly, get_schedules() only retrieves schedules from schedule:cron and schedule:time:{datetime} lists.

Steps to Reproduce

from datetime import timedelta
from taskiq_redis import ListRedisScheduleSource

source = ListRedisScheduleSource(url="redis://localhost:6379/0")

@broker.task
async def my_task():
    pass

# This creates schedule:data:{id} but NOT schedule:interval or similar
schedule = await my_task.schedule_by_interval(
    source=source,
    interval=timedelta(seconds=300),
)

# Returns empty list - schedule is lost
schedules = await source.get_schedules()  # []

Expected Behavior

schedule_by_interval should work with ListRedisScheduleSource, either by:

1. Adding support for interval schedules (e.g., schedule:interval list)

Workaround

Use schedule_by_cron() instead of schedule_by_interval():

# Convert interval to cron expression
# 300 seconds = */5 * * * *
schedule = await my_task.schedule_by_cron(
    source=source,
    cron="*/5 * * * *",
)

However, cron cannot go below minutes, for example, every 10 seconds.

Environment

• taskiq-redis version: 1.2.0
• Python version: 3.13.1

[s3rius]

That is a quite critical problem. Okay, will update tomorrow.