feat: add backfills logic

backend/src/api/routers/backfill.py

@@ -0,0 +1,119 @@
+import json
+from datetime import datetime
+from typing import Annotated, Any
+
+import asyncpg
+from dishka.integrations.fastapi import DishkaRoute, FromDishka
+from fastapi import APIRouter, HTTPException, Query
+from pydantic import BaseModel
+
+router = APIRouter(prefix="/api", tags=["backfill"], route_class=DishkaRoute)
+
+JOBS_CHANGED_CHANNEL = "jobs_changed"
+
+
+class BackfillRequest(BaseModel):
+    account_id: int
+    chat_id: int
+    media: bool = False
+
+
+class FetchMediaRequest(BaseModel):
+    account_id: int
+    chat_id: int
+    message_id: int
+
+
+class EnqueueResponse(BaseModel):
+    job_id: int
+
+
+class JobView(BaseModel):
+    id: int
+    account_id: int
+    kind: str
+    status: str
+    params: dict[str, Any]
+    cursor: dict[str, Any] | None
+    progress: dict[str, Any]
+    flood_waits: int
+    attempts: int
+    error: str | None
+    created_at: datetime
+    started_at: datetime | None
+    finished_at: datetime | None
+
+
+def _to_view(row: asyncpg.Record) -> JobView:
+    data = dict(row)
+    data["params"] = json.loads(data["params"])
+    data["progress"] = json.loads(data["progress"])
+    data["cursor"] = json.loads(data["cursor"]) if data["cursor"] is not None else None
+    return JobView(**data)
+
+
+async def _enqueue(
+    pool: asyncpg.Pool, account_id: int, kind: str, params: dict[str, Any]
+) -> int:
+    job_id = await pool.fetchval(
+        "INSERT INTO jobs (account_id, kind, params) "
+        "VALUES ($1, $2, $3::jsonb) RETURNING id",
+        account_id,
+        kind,
+        json.dumps(params),
+    )
+    await pool.execute(f"NOTIFY {JOBS_CHANGED_CHANNEL}")
+    return job_id
+
+
+@router.post("/backfill", status_code=201)
+async def enqueue_backfill(
+    pool: FromDishka[asyncpg.Pool], body: BackfillRequest
+) -> EnqueueResponse:
+    job_id = await _enqueue(
+        pool,
+        body.account_id,
+        "backfill",
+        {"chat_id": body.chat_id, "media": body.media},
+    )
+    return EnqueueResponse(job_id=job_id)
+
+
+@router.post("/media/fetch", status_code=201)
+async def enqueue_fetch_media(
+    pool: FromDishka[asyncpg.Pool], body: FetchMediaRequest
+) -> EnqueueResponse:
+    job_id = await _enqueue(
+        pool,
+        body.account_id,
+        "fetch_media",
+        {"chat_id": body.chat_id, "message_id": body.message_id},
+    )
+    return EnqueueResponse(job_id=job_id)
+
+
+@router.get("/jobs")
+async def list_jobs(
+    pool: FromDishka[asyncpg.Pool],
+    account_id: Annotated[int, Query()],
+    status: Annotated[str | None, Query()] = None,
+) -> list[JobView]:
+    if status is None:
+        rows = await pool.fetch(
+            "SELECT * FROM jobs WHERE account_id = $1 ORDER BY id DESC", account_id
+        )
+    else:
+        rows = await pool.fetch(
+            "SELECT * FROM jobs WHERE account_id = $1 AND status = $2 ORDER BY id DESC",
+            account_id,
+            status,
+        )
+    return [_to_view(row) for row in rows]
+
+
+@router.get("/jobs/{job_id}")
+async def get_job(pool: FromDishka[asyncpg.Pool], job_id: int) -> JobView:
+    row = await pool.fetchrow("SELECT * FROM jobs WHERE id = $1", job_id)
+    if row is None:
+        raise HTTPException(status_code=404, detail="job not found")
+    return _to_view(row)