qmlutil

Utilities for QuakeML

In a perfect world, all professional seismological applications speak QuakeML. This is for when that doesn't happen.

About

This is the Nevada Seismological Lab's python package for dealing with "QML", the QuakeML Model Language schema. It mostly contains housekeeping classes and functions for dealing with python dicts and lists adhering to the QuakeML v1.2 schema. It contains some schema converter classes, and a few plugins for using 3rd party libraries.

This module is a work-in-progress, and may change until a 1.0 release. That said, the goal is to keep the current methods and API stable up to and through the 1.0. NSL is currently using this lib in production, so it behooves us not to change the API as much as possible. More/better doc to come, hopefully.

NSL builds all python libraries as wheels; to build qmlutil, clone the repo and build an installable wheel in the top-level directory:

% git clone https://github.com/NVSeismoLab/qmlutil
% pip wheel -w /tmp ./

Philosophy

This module aims to:

be written in pure python
have zero (or minimal) dependencies
prefer python data structures over classes

Rather than map classes to classes, and have to write custom JSON, XML, etc encoders, this module attempts to do schema translation using python dicts, lists, etc as fundamental units of records, rows, and documents. There are many good existing implementations of QuakeML classes, including those distributed by quakeml.org, and the excellent ObsPy framework. Those or other custom classes can easily be built using the structures from this module. Being in pure python allows this lib to be used by other interpreters, i.e. pypy. Another goal of this project is to produce structures which can easily be serialized to other wire formats, i.e. JSON, msgpack, Avro, or Protocol Buffers.

The core of this module has no external dependencies. Serialization to XML is done through the xmltodict module, which is included in this package. There are plugins, which do have external dependencies. For instance, serialization to XML is pure python, but the XSD schema validator currently depends on the lxml package (validating is highly recommended in production).

Description

Core

qmlutil.css - Convert between CSS3.0 and QML1.2 schemas (currently only CSS->QML)
qmlutil.ichinose - Convert Ichinose moment tensor text output to QML1.2
qmlutil.lib - Contains vendored packages
qmlutil.xml - Serialize a python QML structure (dicts + lists) to XML/QuakeML

Require other python libs

qmlutil.plugins.antelope_db - Contains converter classes for Antelope CSS databases
qmlutil.plugins.xml - Contains classes for more advanced XML tasks that require libxml2

Dependencies

We use obspy to convert quakeml to seiscomp3ml. obspy has the following system level requirements: sudo apt-get install libxml2-dev libxslt1-dev

There are no deps for core. The plugins modules have various vendor reqs:

The antelope_db plugin requires the proprietary antelope packages and NSL's curds2 DBAPI driver
The xml plugin requires the lxml package

License

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0