LIGO-Virgo Alert System
The LIGO-Virgo Alert System (LVAlert) is a prototype notification service built on the xmpp (jabber) protocol and the pubsub extension. It provides a basic notification tool which allows multiple producers and consumers of notifications. To use the service, you must first visit the
account activation web page to set your LVAlert password. Client tools are provided in LSCSoft to send notifications, to administer subscriptions and nodes in the service, and to listen for notifications. You can read about using the service at the
LVAlertHowto page. There is also a page with
technical information for administrators.
How it works
An entity publishes information to a node (think of it like a channel). Other entities subscribe to that node (channel) and then listen for content published on the channel. The listener can be configured to take an action upon receipt of an alert.
Example use cases
Sample use case #1: a GRB alert arrives and gets published to the
external_swift_grb
node, and the CBC and Burst groups each have listeners waiting for the alerts. The CBC group listener is configured to run an inspiral search if the GRB alert indicates either a short GRB or has no duration information. The burst group listener is configured to run an X-Pipeline search for each GRB alert.
Sample use case #2: an entity (person, group or service) publishes a candidate event into the Gravitational Wave Candidate Event Database (
GraceDB). The
GraceDB service, at the time of receiving the event, sends a notice to the pubsub service. People who are interested in following up such candidates can listen for the notification and take the appropriate action upon receipt of the notification. For example, a sky-localization or parameter estimate job might be carried out.
Project Librarian
Tanner Prestegard
<tanner.prestegard@ligo.org> and Alexander Pace
<alexander.pace@ligo.org> are the LVAlert project librarians.
Documentation
You can read about using the service at the
LVAlertHowto page.
You can set or re-set your LVAlert password on the
account activation web page.
There is also some
documentation for administrators.
Downloading / Installing
Scientific Linux
Follow the
instructions on configuring your machine to use the LSCSoft yum repository up to but not including the
yum groupinstall
. After configuring your yum repository, execute
yum install ligo-lvalert
and you are done.
Debian
Follow the
instructions for configuring your machine to use the LSCSoft Debian repository, up to but not including the
aptitude install lscsoft-all
command. Once this is done, execute
aptitude install python-ligo-lvalert
to install the LVAlert client package.
MacPorts
The LVAlert client tools are available in MacPorts as
ligo-lvalert
.
PyPI (the Python Package Index)
The client tools are also available via
PyPI:
pip install ligo-lvalert
NOTE:I had some trouble installing the client with pip in a virtual environment on El Capitan 10.11.4, with Python 2.7.11. Here is the sequence of steps I used:
sudo port install py27-pip
sudo port select --set python python27
sudo port select --set python2 python27
sudo port select --set pip pip27
sudo port install py27-virtualenv
cd /opt/local/bin
sudo ln -s /opt/local/Library/Frameworks/Python.framework/Versions/2.7/bin/virtualenv virtualenv
sudo port install libxml2
sudo port install py27-libxml2
sudo port install swig
sudo port install py27-m2crypto
cd ~/
virtualenv --system-site-packages my_virtual_env
source my_virtual_env/bin/activate
pip install ligo-lvalert
Tarball / Git Repository
Source tarballs are available on
software.ligo.org (look for ligo-lvalert-X.Y.tar.gz).
The
GraceDB client package is available in the lscsoft group at git.ligo.org:
Note that code at the head of the git repository may be volatile or unstable. One should know what they are doing if using this option.
Once downloaded, installation is the normal python distutils procedure; cd into the source directory and execute
python setup.py install [--prefix=/TARGET/INSTALLATION/DIRECTORY]
.
Bug Reporting
Please report bugs using the
LVAlert Redmine area.
Mailing Lists
Discussion of the LVAlert software and service should be directed to the
DASWG mailing list.
Contributors
- Patrick Brady
- Brian Moe
- Branson Stephens
- Kipp Cannon
- Reed Essick
- Alexander Pace
- Tanner Prestegard
--
BransonStephens - 18 Aug 2015