Function fetchNewEmails

apps/sim/lib/webhooks/polling/imap.ts:239–342

(
  client: ImapFlow,
  config: ImapWebhookConfig,
  requestId: string,
  logger: Logger
)

}

async function fetchNewEmails(
  client: ImapFlow,
  config: ImapWebhookConfig,
  requestId: string,
  logger: Logger
) {
  const emails: Array<{
    uid: number
    mailboxPath: string
    envelope: FetchMessageObject['envelope']
    bodyStructure: FetchMessageObject['bodyStructure']
    source?: Buffer
  }> = []

  const mailboxes = getMailboxesToCheck(config)
  const latestUidByMailbox: Record<string, number> = { ...(config.lastProcessedUidByMailbox || {}) }
  const uidValidityByMailbox: Record<string, string> = { ...(config.uidValidityByMailbox || {}) }

  const maxEmails = config.maxEmailsPerPoll || 25
  let totalEmailsCollected = 0

  for (const mailboxPath of mailboxes) {
    if (totalEmailsCollected >= maxEmails) break

    try {
      const mailbox = await client.mailboxOpen(mailboxPath)

      const currentUidValidity = mailbox.uidValidity.toString()
      const storedUidValidity = uidValidityByMailbox[mailboxPath]

      if (storedUidValidity && storedUidValidity !== currentUidValidity) {
        logger.warn(
          `[${requestId}] UIDVALIDITY changed for ${mailboxPath} (${storedUidValidity} -> ${currentUidValidity}), discarding stored UID`
        )
        delete latestUidByMailbox[mailboxPath]
      }
      uidValidityByMailbox[mailboxPath] = currentUidValidity

      let searchCriteria: Record<string, unknown> = { unseen: true }
      if (config.searchCriteria) {
        if (typeof config.searchCriteria === 'object') {
          searchCriteria = config.searchCriteria
        } else if (typeof config.searchCriteria === 'string') {
          try {
            searchCriteria = JSON.parse(config.searchCriteria)
          } catch {
            logger.warn(`[${requestId}] Invalid search criteria JSON, using default`)
          }
        }
      }

      const lastUidForMailbox = latestUidByMailbox[mailboxPath]

      if (lastUidForMailbox) {
        searchCriteria = { ...searchCriteria, uid: `${lastUidForMailbox + 1}:*` }
      }

      if (config.lastCheckedTimestamp) {