Function resolveOne

src/bridge/inboundAttachments.ts:68–117

* Fetch + write one attachment. Returns the absolute path on success, * undefined on any failure.

(att: InboundAttachment)

 * undefined on any failure.
 */
async function resolveOne(att: InboundAttachment): Promise<string | undefined> {
  const token = getBridgeAccessToken()
  if (!token) {
    debug('skip: no oauth token')
    return undefined
  }

  let data: Buffer
  try {
    // getOauthConfig() (via getBridgeBaseUrl) throws on a non-allowlisted
    // CLAUDE_CODE_CUSTOM_OAUTH_URL — keep it inside the try so a bad
    // FedStart URL degrades to "no @path" instead of crashing print.ts's
    // reader loop (which has no catch around the await).
    const url = `${getBridgeBaseUrl()}/api/oauth/files/${encodeURIComponent(att.file_uuid)}/content`
    const response = await axios.get(url, {
      headers: { Authorization: `Bearer ${token}` },
      responseType: 'arraybuffer',
      timeout: DOWNLOAD_TIMEOUT_MS,
      validateStatus: () => true,
    })
    if (response.status !== 200) {
      debug(`fetch ${att.file_uuid} failed: status=${response.status}`)
      return undefined
    }
    data = Buffer.from(response.data)
  } catch (e) {
    debug(`fetch ${att.file_uuid} threw: ${e}`)
    return undefined
  }

  // uuid-prefix makes collisions impossible across messages and within one
  // (same filename, different files). 8 chars is enough — this isn't security.
  const safeName = sanitizeFileName(att.file_name)
  const prefix = (
    att.file_uuid.slice(0, 8) || randomUUID().slice(0, 8)
  ).replace(/[^a-zA-Z0-9_-]/g, '_')
  const dir = uploadsDir()
  const outPath = join(dir, `${prefix}-${safeName}`)

  try {
    await mkdir(dir, { recursive: true })
    await writeFile(outPath, data)
  } catch (e) {
    debug(`write ${outPath} failed: ${e}`)
    return undefined
  }

  debug(`resolved ${att.file_uuid} → ${outPath} (${data.length} bytes)`)
  return outPath
}

/**
 * Resolve all attachments on an inbound message to a prefix string of