proxy is a multi-topic, on-demand repeater for message streams.

Usage

Start the proxy with your desired prefix:

$ rosrun proxy proxy _prefix:=/proxy

Subscribe to a repeated topic (suppose you have a topic /scan):

$ rostopic echo /proxy/scan

Notes

If you do not need support for multiple topics or on-demand subscription, you could use the relay node from topic_tools.

proxy will only relay topics whose messages are defined on the system where proxy runs. This limitation exists because publishers are required to advertise some information that is not available through the rosmaster API, such as the message hash and message definition.

If you run multiple proxy instances, the proxies will repeat each other's topics, but they will not create a loop. You can use this to create message chains like the following:

/proxy3/proxy2/proxy1/scan

When you first subscribe to that topic, proxy 3 will subscribe to proxy 2, which will subscribe to proxy 1, which will read in the original message.