Delete message on receive

[fiznool]

Thanks for a great queue library!

For my application, I'm looking to delete a message as it is received. I can currently do this by issuing a deleteMessage straight after a receiveMessage, but I'd like to go one step further and add support for this in the receiveMessage lua script, so that the delete happens atomically.

I was wondering whether you'd accept a PR which implements this functionality.

Here's what I'm thinking:

• Allow a vt of -1 - this indicates that a message should be deleted when it is pulled off the queue.
• Check if vt is -1 in the lua script - if so, run the zrem and hdel operations to delete the message.

If reusing the vt variable isn't desirable, perhaps a new option could be used instead, for example remove_on_receive.

[smrchy]

This is a good enhancement. I will implement it hopefully this week.

[smrchy]

I added a 'popMessage' method.

Docs: https://github.com/smrchy/rsmq#popmessage

Hope this does what you need.

[fiznool]

Marvellous. I'll test this out right away. Thanks for the speedy implementation!

[smrchy]

Please close this issue if it works for you.

[fiznool]

Works great, thanks!

[markotom]

Is it a good approach to set a TTL to each message?

[smrchy]

If you need a TTL (only valid till some_timestamp) then you should probably add this from within your application. Just add a ttl to your message payload. If the ttl is reached just delete the message and don't work on it.

A TTL feature for RSMQ is not planned as this would make regular housekeeping necessary which is something i'd like to avoid.