Data Services Newsletter

Volume 19 : No 2 : Summer 2017

IRIS Federator updates to support more use cases and flexibility

The IRIS DMC is pleased to announce important new updates to our irisws-fedcatalog web service, the public interface to the IRIS Federator. The IRIS Federator is a database and web service that gives users the ability to find distributed time series metadata holdings from FDSN data centers around the world. Since its introduction in 2015, the catalog has grown to include listings for 16 data centers. The catalog is refreshed, by harvesting metadata from each center, every 24 hours.

The most recent release offers additional flexibility in searching and filtering time series metadata listings from multiple data centers. A key update is the ability to request a station listing in addition to the channel listing previously offered. Also, users can now limit the results to a list of selected data centers.

As before, the results of a query to the Federator are in a form ready for submission to the respective data centers. Support for the Federator has been integrated into some of the IRIS DMC’s tools, notably FetchData (command line) and irisFetch.m (MATLAB) with more to come in the future.

The irisws-fedcatalog v1.1.1 web service release offers the following new features:

(1) The “station” option for the level query parameter.

e.g., &level=station

With this option metadata are returned at the station-level, offering a quick summary of the holdings available for a particular time range or network selection.

(2) The datacenter query parameter

e.g., &datacenter=IRIS

The user can specify one or more datacenters to limit search results. Wildcards and the negation symbol (-) are permitted.

(3) The datacenters endpoint now offers a format query parameter

e.g., datacenters?format=JSON

Datacenter information can now be returned in TEXT, HTML, or JSON formats (JSON is the default).

The irisws-fedcatalog documentation page and extra help contain additional information and examples of how you can incorporate this service into your scripts. The URL builder offers a graphical interface into generating Fedcatalog requests. Take it for a spin at http://service.iris.edu/irisws/fedcatalog/docs/1/builder/.

by Chad Trabant (IRIS Data Management Center)