Add cron jobs (#60)

* feat: finish up cron jobs

* feat: clean up

api/backend/job/cron_scheduling/cron_scheduling.py

@@ -0,0 +1,100 @@
+import datetime
+from typing import Any
+import uuid
+from api.backend.database.common import insert, query
+from api.backend.models import CronJob
+from apscheduler.schedulers.background import BackgroundScheduler  # type: ignore
+from apscheduler.triggers.cron import CronTrigger  # type: ignore
+
+from api.backend.job import insert as insert_job
+import logging
+
+LOG = logging.getLogger("Cron Scheduler")
+
+
+def insert_cron_job(cron_job: CronJob):
+    query = """
+    INSERT INTO cron_jobs (id, user_email, job_id, cron_expression, time_created, time_updated)
+    VALUES (?, ?, ?, ?, ?, ?)
+    """
+    values = (
+        cron_job.id,
+        cron_job.user_email,
+        cron_job.job_id,
+        cron_job.cron_expression,
+        cron_job.time_created,
+        cron_job.time_updated,
+    )
+
+    insert(query, values)
+
+    return True
+
+
+def delete_cron_job(id: str, user_email: str):
+    query = """
+    DELETE FROM cron_jobs
+    WHERE id = ? AND user_email = ?
+    """
+    values = (id, user_email)
+    insert(query, values)
+
+    return True
+
+
+def get_cron_jobs(user_email: str):
+    cron_jobs = query("SELECT * FROM cron_jobs WHERE user_email = ?", (user_email,))
+
+    return cron_jobs
+
+
+def get_all_cron_jobs():
+    cron_jobs = query("SELECT * FROM cron_jobs")
+
+    return cron_jobs
+
+
+def insert_job_from_cron_job(job: dict[str, Any]):
+    insert_job(
+        {
+            **job,
+            "id": uuid.uuid4().hex,
+            "status": "Queued",
+            "result": "",
+            "chat": None,
+            "time_created": datetime.datetime.now(),
+            "time_updated": datetime.datetime.now(),
+        }
+    )
+
+
+def get_cron_job_trigger(cron_expression: str):
+    expression_parts = cron_expression.split()
+
+    if len(expression_parts) != 5:
+        print(f"Invalid cron expression: {cron_expression}")
+        return None
+
+    minute, hour, day, month, day_of_week = expression_parts
+
+    return CronTrigger(
+        minute=minute, hour=hour, day=day, month=month, day_of_week=day_of_week
+    )
+
+
+def start_cron_scheduler(scheduler: BackgroundScheduler):
+    cron_jobs = get_all_cron_jobs()
+
+    LOG.info(f"Cron jobs: {cron_jobs}")
+
+    for job in cron_jobs:
+        queried_job = query("SELECT * FROM jobs WHERE id = ?", (job["job_id"],))
+
+        LOG.info(f"Adding job: {queried_job}")
+
+        scheduler.add_job(
+            insert_job_from_cron_job,
+            get_cron_job_trigger(job["cron_expression"]),
+            id=job["id"],
+            args=[queried_job[0]],
+        )