_ (py27, py34, py35, py36)

This repository is intended to contain the source code for three of the web services of EIDA NG: (i) the federator, (ii) stationlite and (iii) the mediator.

Federator: Federate fdsnws-station, fdsnws-dataselect, and eidaws-wfcatalog requests across all EIDA nodes. This means, a user can issue a request against a federator endpoint without having to know where the data is hosted. In order to discover the information location the eidaws-stationlite web service is used.

StationLite: A lightweight fdsnws-station web service providing routing information. The stream epoch information is returned fully resolved (Stream epochs do not contain wildcard characters anymore.). The information location is harvested making use of eidaws-routing configuration files and fdsnws-station.

Mediator: This service allows queries across different web service domains, e.g., fdsnws-station and fdsnws-dataselect. Example: Retrieve waveform data for all stations within a lat-lon box.

Currently, we provide an alpha version of the federator service for fdsnws-station, fdsnws-dataselect and eidaws-wfcatalog.

Besides an alpha version of the stationlite service is implemented.

• Installation
• Run the Test WSGI servers
• StationLite harvesting
• Logging (application level)
• Missing features and limitations

• Development
• Docker

The examples bellow use the built-in Flask server, which is not recommended to use in production. In production environments the usage of a WSGI server should be preferred. An exemplary setup with mod_wsgi and Apache2 is described in the section Deploying to a webserver <https://github.com/EIDA/mediatorws/tree/master/docs/installing/development.rst#Deploying to a webserver>. Alternatively use Gunicorn or uWSGI.

To launch a local test WSGI server (NOT for production environments) enter:

(venv) $ eida-federator --start-local --tmpdir='/path/to/tmp'

For further configuration options invoke

(venv) $ eida-federator -h

The service currently writes temporary files to the tmpdir. Make sure that plenty of space is available.

To launch a local test WSGI server (NOT for production environments) enter:

(venv) $ eida-stationlite --start-local URL

URL is a database url as described at the SQLAlchemy documentation. For further configuration options invoke

(venv) $ eida-stationlite -h

Add the repository directory to your PYTHONPATH. Then, the server can be started as

$ python -m eidangservices.mediator.server --port=5001 --tmpdir='/path/to/tmp'

The server writes temporary files to the tmpdir, so this directory will fill up. It is recommended to purge this directory regularly, e.g., using a tool like tmpreaper.

The stationlite webservice data is stored in a database which periodically must be harvested. This is done with eida-stationlite-harvest. By means of the eidaws-routing configuration files and the fdsnws-station webservice eida-stationlite-harvest collects and updates the database. Information on how to use eida-stationlite-harvest is available with

(venv) $ eida-stationlite-harvest -h

In addition the software suite contains an empty exemplary preconfigured SQLite database (db/stationlite.db.empty) which must be filled initially after installing the stationlite webservice. I.e.

(venv) $ cd $PATH_INSTALLATION_DIRECTORY/mediatorws/
(venv) $ cp -v db/stationlite.db.empty db/stationlite.db
(venv) $ eida-stationlite-harvest sqlite:///$(pwd)/db/stationlite.db

Note, that harvesting may take some time until completed.

For debugging purposes EIDA NG webservices also provide logging facilities. Simply configure your webservice with a logging configuration file. Use the INI logging configuration file format. In case initialization failed a fallback SysLogHandler is set up:

fallback_handler = logging.handlers.SysLogHandler('/dev/log',
                                                  'local0')
fallback_handler.setLevel(logging.WARN)
fallback_formatter = logging.Formatter(
    fmt=("<XXX> %(asctime)s %(levelname)s %(name)s %(process)d "
         "%(filename)s:%(lineno)d - %(message)s"),
    datefmt="%Y-%m-%dT%H:%M:%S%z")
fallback_handler.setFormatter(fallback_formatter)

An exemplary logging configuration using a SysLogHandler is located at $PATH_INSTALLATION_DIRECTORY/mediatorws/config/syslog.conf. At $PATH_INSTALLATION_DIRECTORY/mediatorws/config/logging.config a StreamHandler is configured.

• AAI of the fdsnws-dataselect service is not implemented yet
• stationlite currently implements the eidaws-routing interface only partly (e.g. format={post,get})
• For issues also visit https://github.com/EIDA/mediatorws/issues.