# Ads Redis Key Inventory

| Key pattern | Writer(s) | Reader(s) | Value type | TTL | Notes |
| --- | --- | --- | --- | --- | --- |
| `box:app:adpool:{adType}` | `AdPoolService.rebuildPoolForType` (via `CacheSyncService.rebuildAdsCacheByType`/warm cache) | `readAdPoolEntriesWithLegacySupport` → used by `AdService.getAdForPlacement` and `HomepageService.getAdsByType` | JSON array of `AdPoolEntry` | none | Canonical pool keyed by `AdType`. Writers select `[id,adType,advertiser,title,adsContent,adsCoverImg,adsUrl,imgSource,startDt,expiryDt,seq]` and preserve `seq`-ascending order. Legacy module-keyed pool is rehydrated once and deleted after a warm rebuild.
| `app:adpool:{adsModuleId}` | *None (legacy)* | `readAdPoolEntriesWithLegacySupport` (fallback path that looks up `AdsModule` by `adType`) | JSON array (legacy schema) | none | Transitional key used only when the new `box:app:adpool` pool is missing. The helper logs a warning, writes the normalized entries into the `adType` pool, and never falls back again.
| `app:ad:by-id:{adId}` | `CacheSyncService.rebuildSingleAdCache` (triggered by `AdsService.scheduleAdRefresh`) | `AdService.fetchAdDetails` (placement), `HomepageService.fetchAdDetails` | JSON object (per-ad payload: `id,advertiser,title,adsContent,adsCoverImg,adsUrl,imgSource,adType,startDt,expiryDt,seq`) | ~300s (`CacheSyncService.AD_CACHE_TTL`) | Per-ad cache entry with short TTL to keep metadata fresh. Writers delete the key when the ad is inactive or missing.

No Ads keys currently live without writers/readers except for the legacy `app:adpool:{adsModuleId}` fallback. The canonical `box:app:adpool:{adType}` should remain the single source of truth once caches rebuild and the legacy key is pruned.