message_size_limit should block incoming messages exceeding that limit

[alepez]

Start a broker with option message_size_limit set to 512
Publish a message of 10MB

Expected:

Broker stop handling the message when 512 bytes of payload has arrived, then drop the message.

Actual:

Broker receives 10MB of data, then drop the message. Process' memory usage increase of at least 10MB.

[karlp]

it has to receive the message to drop it. The remote client is still sending that data, you've got to swallow it, or disconnect the client.

[alepez]

I guess there isn't any option to make the broker to disconnect clients not respecting payload size, am I right?

[ralight]

You are correct, but actually this should be possible in 1.5.

[jamesmyatt]

I assume that currently messages that exceed message_size_limit will just be swallowed. Is this correct?

If you're going to disconnect clients for exceeding message_size_limit, then you also need an option to prevent a bridge from sending messages that exceed the limit too, e.g. bridge_outgoing_message_size_limit.

[ralight]

I'm bumping this to 1.6 as it got mised in 1.5, sorry for that.

[ralight]

max_packet_size was added in version 1.6. Bridge control will be in 1.7.