Method getCache

src/utils/img-caches.js:49–80

(signature)

    const parts = String(stamp).match(/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})Z$/)
    if (!parts) return null
    const signedAt = Date.UTC(+parts[1], +parts[2] - 1, +parts[3], +parts[4], +parts[5], +parts[6])
    if (!Number.isFinite(signedAt)) return null
    return signedAt + expires * 1000
  } catch {
    return null
  }
}

/**
 * ¿Sigue sirviendo esta URL cacheada? Manda la caducidad firmada; si la URL no la lleva,
 * manda la antigüedad de la entrada.
 *
 * @param {string} url
 * @param {number|null} cachedAt - epoch ms en que se guardó, o null si no se sabe (modo file)
 * @returns {boolean}
 */
const cachedUrlIsUsable = (url, cachedAt) => {
  const expiry = presignedUrlExpiryMs(url)
  if (expiry !== null) return Date.now() + EXPIRY_SAFETY_MARGIN_MS < expiry
  if (!Number.isFinite(cachedAt)) return false
  return Date.now() - cachedAt <= UNKNOWN_EXPIRY_TTL_MS
}
// ~500 B por entrada (clave hex de 64 + URL) → 512 entradas < 0.5 MB.
const IMAGE_CACHE_MAX_ENTRIES = 512

class imgCacheManager {
  constructor() {
    this.cacheMap = new Map()
    if (config.cacheMode === 'file') {
      fs.mkdirSync(resolveRuntimePath('caches'), { recursive: true })
    }
  }

  cacheIsExist(signature) {
    try {