2.3.1. Echo Participant

This Participant prints in stdout all the discovery information and/or user data that is received by the DDS Router.

In the case of discovery traces, messages such as the following will be displayed:

New endpoint discovered: Endpoint{<endpoint_guid>;<endpoint_kind>;<topic>}.

For data reception messages, the traces show the following information:

Received data in Participant: <participant_id> in topic: <topic>.

These logs contain the Participant Name of the participant that has originally received the message, and the Topic where this message has been received. Additionally, extra information such as the data Payload (in hexadecimal format) and source Endpoint Guid is displayed in verbose mode:

In Endpoint: <endpoint_guid> from Participant: <participant_id> in topic: <topic> payload received: <payload> with specific qos: <specific_qos>.

Notice that this Payload is the same that a standard DDS DataReader will receive if it is connected to one of the Participants of the DDS Router.

Note

This Participant does not perform any discovery or data reception functionality.

2.3.1.1. Use case

Use this Participant in order to see in stdout the data that is being relayed by the router, as well as information regarding discovery events. All the data received by any of the Participants of the router will be printed (if data is true) with its topic and source guid, along with the payload (in verbose mode).

2.3.1.2. Kind aliases

  • echo

2.3.1.3. Configuration

The Echo Participant accepts three different optional parameters:

  • discovery: Whether to echo information regarding discovery events. Defaults to true.

  • data: Whether to echo information regarding user data reception. Defaults to false.

  • verbose: Display detailed information about the user data received (if data set to true). Defaults to false.

2.3.1.4. Configuration Example

- name: echo_participant     # Participant Name = echo_participant
  kind: echo
  data: true                 # Print a trace with every arrival of user data
  verbose: true              # Show detailed information on user data reception
  discovery: false           # Do not print traces regarding discovery events