1  """
 2  dashboard_cache table reader.
 3  
 4  The precompute-dashboard.js cron populates this table every 10 minutes.
 5  FastAPI reads it first; falls back to live queries on miss.
 6  """
 7  
 8  import json
 9  from db import fetchone
10  
11  
12  async def get_cached(key: str) -> dict | list | None:
13      """Return parsed JSON from dashboard_cache if fresh, else None."""
14      row = await fetchone(
15          "SELECT cache_value FROM dashboard_cache "
16          "WHERE cache_key = $1 AND expires_at > NOW()",
17          key,
18      )
19      if row and row.get("cache_value"):
20          return json.loads(row["cache_value"])
21      return None
22  
23  
24  async def get_many(keys: list[str]) -> dict:
25      """Fetch multiple cache keys in one call. Returns {key: value} for hits."""
26      if not keys:
27          return {}
28      from db import fetchall
29      placeholders = ", ".join(f"${i+1}" for i in range(len(keys)))
30      rows = await fetchall(
31          f"SELECT cache_key, cache_value FROM dashboard_cache "
32          f"WHERE cache_key IN ({placeholders}) AND expires_at > NOW()",
33          *keys,
34      )
35      return {r["cache_key"]: json.loads(r["cache_value"]) for r in rows}