Using DPSE With Mixed Connext Micro and Professional Applications

This example contains a Connext Micro-based publishing application and two subscribing applications. Connext Micro 2.4.14 was used.

for a simple IDL-defined data type. "example_subscriber_1" uses a listener to be notified of events, and "example_subscriber_2" uses a WaitSet.

The purpose of this example is to demonstrate how static endpoint discovery (DPSE) can be used between a publisher and subscriber.

Note that actual safety-certified libraries generated from the RTI Connext Micro Cert product only implement the static DPSE discovery plugin, so DPDE is not an option.

Source Overview

A simple "example" type, containing a message string, is defined in example.idl.

For the type to be useable by Connext Micro, type-support files must be generated that implement a type-plugin interface. rtiddsgen can be invoked manually, with an example command like this:

%RTIMEHOME%/rtiddsgen/scripts/rtiddsgen -micro -language C -create typefiles ./example.idl

The generated source files are example.c, exampleSupport.c, and examplePlugin.c. Associated header files are also generated.

The DataWriter and DataReaders for this type are created and used in example_publisher.c and example_subscriber_1.c and example_subscriber_2.c, respectively. Each application has its own DomainParticipant since the intent is that the executables may run independently of each other.

Generated Files Overview

example_publisher.c: This file contains the logic for creating a Publisher and a DataWriter, and sending data.

example_subscriber_1.c: This file contains the logic for creating a Subscriber and a DataReader, a DataReaderListener, and listening for data.

example_subscriber_2.c: This file contains the logic for creating a Subscriber and a DataReader, a WaitSet, and how to use the WaitSet to be notified of events.

examplePlugin.c: This file creates the plugin for the example data type. This file contains the code for serializing and deserializing the example type, creating, copying, printing and deleting the example type, determining the size of the serialized type, and handling hashing a key, and creating the plug-in.

exampleSupport.c This file defines the example type and its typed DataWriter, DataReader, and Sequence.

example.c This file contains the APIs for managing the example type.

Compiling w/ cmake

The following assumptions are made:

On Windows

> cd your\project\directory 
> %RTIMEHOME%\resource\scripts\rtime-make --config Release --build --name x64Win64VS2017 --target Windows --source-dir . -G "Visual Studio 15 2017 Win64" --delete

The executables can be found in the objs<architecture>\Release directory

Note that there a few variables at the top of main() in both the publisher and subscriber code that may need to be changed to match your system:

// user-configurable values
char *peer = "127.0.0.1";
char *loopback_name = "Loopback Pseudo-Interface 1";
char *eth_nic_name = "Wireless LAN adapter Wi-Fi";
int domain_id = 100;

By default, the remote peer is set to the loopback address (allowing the examples to discover each other on the same machine only) and DDS Domain 100 is used. The names of the network interfaces should match the actual host where the example is running (the defaults work for a Windows 10 machine.)

Running example_publisher and example_subscriber

Using a Windows10 system as the example, run the first subscriber in one terminal with the command:

> objs\x64Win64VS2017\Release\example_subscriber_1.exe 

Run the second subscriber in another terminal with the command:

> objs\x64Win64VS2017\Release\example_subscriber_2.exe 

And run the publisher in a third terminal with the command:

> objs\x64Win64VS2017\Release\example_publisher.exe