Robotics Service Bus

h1. First Steps

h2. Introduction

After having installed RSB, trying some of the included example programs and generally making sure everything works as it should may be a good next step. This page describes some initial experiments that can be carried out after installing RSB.

h2. Starting RSB Programs

Currently, RSB uses "the Spread group communication framework":www.spread.org as its default network transport. Spread requires a dedicated daemon process to be running on at least one host of the network segment. Installation of the Spread libraries and daemon is explained on the [[Installation|installation page]].

# Starting the Spread daemon

If only a single machine is involved, the Spread daemon can be started using the following command:

<pre>

$ /SPREAD_INSTALL_PREFIX/sbin/spread -n localhost

/===========================================================================\

| The Spread Toolkit.                                                       |

| Copyright (c) 1993-2006 Spread Concepts LLC                               |

| All rights reserved.                                                      |

[...]

</pre>

# Starting an RSB Example Program

After the Spread is running, connecting to it can be tested using one the example programs. For instance:

<pre>

$ /RSB_CPP_SOURCE_DIRECTORY/core/build/build/rsb_informer

Elapsed time for 1200 messages sent: 0.06 s

</pre>

If everything goes well, the output should look similar to the above. If the connection to the Spread daemon fails, the output will look similar to the following:

<pre>

$ /RSB_CPP_SOURCE_DIRECTORY/core/build/build/rsb_informer

1311067154364 rsb.spread.SpreadConnection [FATAL]: spread connect error: connection to spread daemon failed due to socket errors

SP_error: (-2) Could not connect. Is Spread running?

terminate called after throwing an instance of 'rsb::CommException'

  what():  Error during connection to spread daemon

Aborted

</pre>

h2. Exchanging Events between two Processes

A more interesting experiment can be conducted by adding a receiving process. The easiest way to do this is using one shell for each process.

# Starting the Receiving Process

<pre>

$ /RSB_CPP_SOURCE_DIRECTORY/core/build/build/rsb_listener

Listener setup finished. Waiting for messages on scope Scope[/example/informer/]

</pre>

# Starting the Informer Process

Like before

<pre>

$ /RSB_CPP_SOURCE_DIRECTORY/core/build/build/rsb_informer

Elapsed time for 1200 messages sent: 0.06 s

</pre>

The @rsb_listener@ process should start to print lots of messages like

<pre>

blub

blub

[...]

</pre>

h2. Observing Events using the @rsblogger@ Program

TBD

More information regarding RSB tools can be found on [[Tools|this page]].