Function loadInstallCountsCache

src/utils/plugins/installCounts.ts:62–143

* Load the install counts cache from disk. * Returns null if the file doesn't exist, is invalid, or is stale (>24h old).

()

 * Returns null if the file doesn't exist, is invalid, or is stale (>24h old).
 */
async function loadInstallCountsCache(): Promise<InstallCountsCache | null> {
  const cachePath = getInstallCountsCachePath()

  try {
    const content = await readFile(cachePath, { encoding: 'utf-8' })
    const parsed = jsonParse(content) as unknown

    // Validate basic structure
    if (
      typeof parsed !== 'object' ||
      parsed === null ||
      !('version' in parsed) ||
      !('fetchedAt' in parsed) ||
      !('counts' in parsed)
    ) {
      logForDebugging('Install counts cache has invalid structure')
      return null
    }

    const cache = parsed as {
      version: unknown
      fetchedAt: unknown
      counts: unknown
    }

    // Validate version
    if (cache.version !== INSTALL_COUNTS_CACHE_VERSION) {
      logForDebugging(
        `Install counts cache version mismatch (got ${cache.version}, expected ${INSTALL_COUNTS_CACHE_VERSION})`,
      )
      return null
    }

    // Validate fetchedAt and counts
    if (typeof cache.fetchedAt !== 'string' || !Array.isArray(cache.counts)) {
      logForDebugging('Install counts cache has invalid structure')
      return null
    }

    // Validate fetchedAt is a valid date
    const fetchedAt = new Date(cache.fetchedAt).getTime()
    if (Number.isNaN(fetchedAt)) {
      logForDebugging('Install counts cache has invalid fetchedAt timestamp')
      return null
    }

    // Validate count entries have required fields
    const validCounts = cache.counts.every(
      (entry): entry is { plugin: string; unique_installs: number } =>
        typeof entry === 'object' &&
        entry !== null &&
        typeof entry.plugin === 'string' &&
        typeof entry.unique_installs === 'number',
    )
    if (!validCounts) {
      logForDebugging('Install counts cache has malformed entries')
      return null
    }