n8n-nodes-imap-advanced

Advanced, generic IMAP community nodes for n8n (Mailcow, Dovecot, Gmail IMAP, Outlook IMAP, etc.).

This package is focused on practical email automation patterns that are hard to build with the default n8n email nodes alone:

• message threading from headers (References, In-Reply-To)
• robust flag/tag updates (including custom IMAP keywords)
• optional attachment download as n8n binary data
• trigger with auto | idle | poll behavior

Included nodes

1) IMAP Advanced

Resource-based action node with these operations:

• Message
  • get
  • search
  • updateFlags
  • move
  • copy
  • delete (adds \Deleted)
  • undelete (removes \Deleted)
  • expunge
• Thread
  • getByMessage
• Mailbox
  • list
  • status

2) IMAP Advanced Trigger

New message trigger with:

• modes: auto, idle, poll
• output formats: headersSnippet, full, raw
• attachment modes: none, metadataOnly, binary
• optional post-processing: mark seen, add flags, move message

Credentials

This package reuses n8n built-in IMAP credentials:

• credential type: imap
• no custom IMAP credential is required

Installation

Community package in n8n

Install as a regular npm package where n8n runs:

npm install n8n-nodes-imap-advanced

or from a local tarball:

npm install /path/to/n8n-nodes-imap-advanced-0.1.0.tgz

Then restart n8n.

Quick workflow example (thread + attachments)

1. IMAP Advanced Trigger (mode=auto, mailbox=INBOX)
2. IMAP Advanced (resource=thread, operation=getByMessage)
3. loop over thread messages
4. IMAP Advanced (resource=message, operation=get, attachmentsMode=binary)
5. process content / attachments
6. IMAP Advanced (resource=message, operation=updateFlags or move)

Threading behavior

Thread:getByMessage strategy:

1. parse References
2. fallback to In-Reply-To
3. optional subject fallback (Subject Fallback = true)

Notes:

• IMAP has no universal thread API like Gmail API.
• Header-based threading is best effort and may vary across servers/mailboxes.

Attachments behavior

For Message:get and Trigger output:

• none: no attachment metadata/content
• metadataOnly: metadata only (filename, mime, size)
• binary: adds n8n binary fields (attachment_0, attachment_1, ... by default)

Attachment filtering options:

• max size (MB)
• allowed MIME list (CSV)
• filename regex

Flags / tags

IMAP “tags” are flags/keywords:

• system flags: \Seen, \Answered, \Flagged, \Deleted, \Draft
• custom keywords: e.g. $n8n_processed, ai-replied

Use Message:updateFlags with:

• add
• remove
• replace

Move behavior

Message:move:

• uses IMAP MOVE capability when server supports it
• otherwise falls back to COPY + \Deleted + expunge equivalent flow

Development

npm install
npm run build

Current limitations

• expunge is mailbox-level in current implementation.
• Threading is single-mailbox oriented.
• IDLE mode includes practical polling safety to remain robust across server behaviors.

License

MIT