check if topic is being published to without subscribing

edit

In our project we want to write a node to check sensor nodes for possible errors. One of the checked criterion is, if the topics of the node are actually published and not just have publisher.

Is it possible to check for published messages or publishing frequency without actually subscribing? The reason behind it is, that some sensors like cameras publishes large amount of data, which slow down the checknode.

Not suitable solutions:

• "rospy.get_published_topics" does not check, if the publisher is publishing at all.
• rostopic hz subscribes the topic
• time saving solutions require subscription at some point

Thank you.

Edit/Solution:

I'm not sure (hence a comment), but there is a chance you could do this using topic statistics.

by gvdhoorn

This is our solution. Thanks.