Deprecated

This was an early prototype and is no longer in development. Current work is being done at https://github.com/ros2/ros2

ros_dds

Prototype system using DDS as the middleware for a ROS like API.

System requirements

You need to install OpenSplice. For now, we're only concerned with the C++ bindings (both API and message generation); the other languages supported by OpenSplice are excluded by these installation instructions.

Ubuntu Linux

At the time of writing, we have packaged OpenSplice 6.3 for 64-bit Ubuntu Precise, Quantal, and Raring. To install on one of those systems, you need to add the OSRF apt repo to your system then install libopensplice63:

# Add the appropriate apt repo (substitute `precise` for the right value):
sudo sh -c 'echo "deb http://packages.osrfoundation.org/gazebo/ubuntu precise main" >  /etc/apt/sources.list.d/gazebo-latest.list'
# Add the osrfoundation.org package repository key
wget http://packages.osrfoundation.org/gazebo.key -O - | sudo apt-key add -
# Update your list of packages
sudo apt-get update
# Install opensplice
sudo apt-get install libopensplice63

Mac OSX

Homebrew

Assuming you have Homebrew installed already, you can do this to get opensplice:

brew tap osrf/ros2
brew install opensplice

The above should download and "pour" a binary bottle on OS X 10.8 and 10.9. You can, however, build it with debug symbols like this:

brew install --with-debug opensplice

Generic build from source

Clone our fork of opensplice, then use our CMake wrapper around their oddball build system:

# Install build-time prerequisites, which on Linux are:
# (see http://www.prismtech.com/opensplice/opensplice-dds-community/building for the full list)
sudo apt-get install gawk flex bison perl
git clone https://github.com/osrf/opensplice.git
cd build
cmake .. -DCMAKE_INSTALL_PREFIX=/tmp/opensplice
make install
# Tell CMake to look there for CMake configuration files
export CMAKE_PREFIX_PATH=/tmp/opensplice:$CMAKE_PREFIX_PATH

Talker / listener example

In the cpp subdirectory, there's a first version of a simplified DDS API, along with example publisher and subscriber applications. It builds like vanilla CMake (assuming that you've already followed one of the installation paths described above):

cd cpp
mkdir build
cd build
cmake ..
make

To run the subscriber:

cd cpp/build
. setup.sh
./subscriber mytopic

To run the publisher:

cd cpp/build
. setup.sh
./publisher mytopic mystring 1000

You should expect to see output like this from the subscriber:

mytopic: mystring
mytopic: mystring
mytopic: mystring
mytopic: mystring

Known limitations

• We're only dealing with string messages (see the definition in cpp/idl/StringMsg.idl).
• The publisher publishes a finite number of messages at a fixed frequency, then stops.
• The subscriber can only subscribe to one topic and it takes several seconds to shut down on Ctrl-C because OpenSplice's internal tear-down handlers are running.
• Before running an OpenSplice program, you need to source the generated cpp/build/setup.sh file (if you don't, you'll get an error like Error in DDS::DomainParticipantFactory::create_participant: Creation failed: invalid handle). The setup.sh is simple, in that it just sets the OSPL_URI environment variable to point to the default XML configuration file. But we need to think about to handle configuration in general.

Releasing a new Ubuntu package

To release a new version of the libopensplice63 debian (rough sketch; we should really use bloom for this step):

• Clone the opensplice-release repo. Update opensplice-release/*/debian/changelog to list the new version.
• Clone the opensplice repo. In there, git submodule init; git submodule update to pull in the submodule content that's required.
• Clone the release-tools repo.
• In the opensplice directory, run: ../release-tools/release.py -r <releasenumber> -a libopensplice63 opensplice <major.minor.patch> <buildpassword>