Rivendell includes full support for the origination and transmission of program associated data (PAD) in realtime, including a Python module (PyPAD) that can be used to create scripts for interfacing Rivendell's PAD feed to most any arbitrary external system. All Rivendell PAD updates are emitted as JSON documents of type padUpdate via TCP port 34289. A typical update looks like: Rivendell ships with a Python 3 module called "pypad" that automates away most of the work involved in reading, parsing and processing the raw JSON data feed described above. A copiously commented example script can be found in the Rivendell source tree at apis/pypad/tests/now_and_next.py. Rivendell can be configured to start one or more PyPAD scripts automatically whenever the "rivendell" systemd service is (re)started. In order to support this, a PyPAD script must meet the following requirements: Accept exactly three command-line arguments as follows: script host-name port-num config The config value should be passed to the pypad.Receiver.setConfigFile() method, and host-name and port-num values should be passed to the pypad.Receiver().start() method. See any of the production PyPAD scripts in the Rivendell sources in apis/pypad/scripts/ for an example. If the script is configurable via a configuration file, provide a sample copy of the configuration file, using wherever possible sane default values along with comments documenting what the various parameters do. The file should have the the same base name as that of the script, but have an .exemplar extension. For example, if the script is called myscript.py, the sample configuration file would be called myscript.exemplar. Install a copy of the script, along with a copy of the sample configuration file (if needed) in the Rivendell PyPAD script directory $(libdir)/rivendell/pypad/. In the RHEL/CentOS reference installation, this directory is /usr/lib64/rivendell/pypad/. The $(libdir) path component evaluates to the value used for the --libdir switch that was passed to the "configure" script when Rivendell was built [default value: /usr/local/lib]. All PyPAD scripts started in this manner will be run under the user/group specified by the PypadOwner= and PypadGroup= directives in the [Identity] section of the rd.conf5 configuration file. See for instructions on enabling a script that has been prepared in this manner.