question Re: ConsumeIMAP - Reset State? in Support Questions

ConsumeIMAP - Reset State?

JohnA — Mon, 15 Jun 2020 08:23:44 GMT

Consumer IMAP - Reset State?

Can anyone tell me how to control state on Consume IMAP (v1.11.4)
I have successfully implemented a flow where I receive emails using the ConsumeIMAP ExtractEmailHeaders and ExtractEmailAttachements, all is working as expected.

I have set the properties:

Delete Messages = false
Mark Message as Read = false

so my emails remain in the INBOX.

I would like a way to "reset" - so that the processor would receive all the emails again, however I can't seem to find where state is controlled.

Stopping and starting the processor does not reset;

Stopping/Starting Nifi does not reset.

Does this processor hold some other state or does it query my provenance to workout where it is up to? Would I need to delete the provenance to reset it?

I was expecting some kinds of state similar to ListSFTP?

Any help appreciated

John

Re: ConsumeIMAP - Reset State?

stevenmatison — Mon, 15 Jun 2020 15:02:07 GMT

@JohnA

Per documentation: https://nifi.apache.org/docs/nifi-docs/components/org.apache.nifi/nifi-email-nar/1.11.0/org.apache.nifi.processors.email.ConsumeIMAP/

State management:

This component does not store state.

If you click Additional Details: https://nifi.apache.org/docs/nifi-docs/components/org.apache.nifi/nifi-email-nar/1.11.0/org.apache.nifi.processors.email.ConsumeIMAP/additionalDetails.html

It goes into some debug steps that may help you understand what is going on.

Unfortunately I think the only way to reset it, would be to delete and create again.

Re: ConsumeIMAP - Reset State?

architect — Thu, 06 Aug 2020 15:42:17 GMT

In reality despite ConsumeIMAP is stateless, the IMAP server holds /Recent flag that is system read-only flag (theoretically within IMAP session, but how Gmail detect unique session is a BlackBox and I was not able to manage it with NiFi ConsumeIMAP client).

If you want to re-fetch all your historical emails I recommend using ConsumePOP3 NiFi component, with the following setting on Gmail server:

Gmail - settings - all - forwarding - Enable POP for all mail

After performing such historical fetch you can disable ConsumePOP3 and continue to work with ConsumeIMAP to consume new messages.