ssnolib: Library for the Simple Standard Name Ontology (SSNO)

A Python library to work with the SSNO ontology. It provides Python classes for ontology concepts and facilitates the creation of RDF files (JSON-LD, TTL, XML). RDF files are both human- and machine-readable, and most importantly, machine-actionable. The library can be integrated into your data (conversion) pipelines.

Features

• Python classes for all SSNO ontology concepts
• Easy creation and export of JSON-LD, TTL, and XML files
• Support for Standard Name Tables (SNT)
• Extensible for HDF5, XML, and YAML formats
• Local web apps (Streamlit, Flask) for management and enrichment
• Compatible with Python 3.8–3.12
• Comprehensive documentation and tutorials

Note: The library version matches the supported ontology version. For example, 1.5.0.1 refers to ontology version 1.5.0 and patch version .1 of the library.

Installation

Install the core library:

pip install ssnolib

Quickstart

Describe a Standard Name and dump it to Turtl

import ssnolib

air_temp = ssnolib.StandardName(
    standardName='air_temperature',
    unit='K',
    description='Air temperature is the bulk temperature of the air, not the surface (skin) temperature.@en')
with open('air_temperature.jsonld', 'w') as f:
    f.write(air_temp.model_dump_ttl())

The serialized TTL file looks like this:

@prefix ssno: <https://matthiasprobst.github.io/ssno#> .

[] a ssno:StandardName ;
    ssno:description "Air temperature is the bulk temperature of the air, not the surface (skin) temperature."@en ;
    ssno:standardName "air_temperature" ;
    ssno:unit <http://qudt.org/vocab/unit/K> .

Describe Standard Name Tables

A Standard Name Table (SNT) defines Standard Names and exists as an RDF file (usually in TTL, XML, or JSON-LD format). The SNT itself is modeled by ssnolib.StandardNameTable. In the following example, we define a SNT with one Standard Name (air_temperature) which is stored in a dcat:Dataset with one dcat:Distribution. The distribution points to a TTL file containing the SNT, which can be downloaded.

import ssnolib
from ssnolib.dcat import Dataset, Distribution

distribution = Distribution(
    title='TTL Table@en',
    downloadURL='https://example.org/cf-standard-name-table.ttl',
    mediaType='text/turtle'
)
snt_dataset = Dataset(
    title='CF Standard Name Table Dataset@en',
    description='The CF Standard Name Table is a controlled vocabulary for climate and forecast metadata.@en',
    distribution=distribution
)
snt = ssnolib.StandardNameTable(
    id="https://doi.org/10.5281/zenodo.12345678",
    title='CF Standard Name Table (latest version)@en',
    dataset=snt_dataset,
    created="2023-10-10",
    standardNames=[air_temp,]
)

The serialized version in TTL format can be obtained by:

print(snt.serialize("ttl", base_uri="https://example.org#"))

which results in:

@prefix dcat: <http://www.w3.org/ns/dcat#> .
@prefix dcterms: <http://purl.org/dc/terms/> .
@prefix ssno: <https://matthiasprobst.github.io/ssno#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<https://doi.org/10.5281/zenodo.12345678> a ssno:StandardNameTable ;
    dcterms:created "2023-10-10"^^xsd:date ;
    dcterms:title "CF Standard Name Table (latest version)"@en ;
    ssno:dataset <https://example.org/#N2f15bceee1cf431688c375b242d2c61b> ;
    ssno:standardNames <https://example.org/#N5542e225237745dfa57de897543fa5c8> .

<https://example.org/#N2f15bceee1cf431688c375b242d2c61b> a dcat:Dataset ;
    dcterms:description "The CF Standard Name Table is a controlled vocabulary for climate and forecast metadata."@en ;
    dcterms:title "CF Standard Name Table Dataset"@en ;
    dcat:distribution <https://example.org/#Ncd83fad310144161b45f7c466d6fd7cc> .

<https://example.org/#N5542e225237745dfa57de897543fa5c8> a ssno:StandardName ;
    ssno:description "Air temperature is the bulk temperature of the air, not the surface (skin) temperature."@en ;
    ssno:standardName "air_temperature" ;
    ssno:unit <http://qudt.org/vocab/unit/K> .

<https://example.org/#Ncd83fad310144161b45f7c466d6fd7cc> a dcat:Distribution ;
    dcterms:title "TTL Table"@en ;
    dcat:downloadURL <https://example.org/cf-standard-name-table.ttl> ;
    dcat:mediaType <https://www.iana.org/assignments/media-types/text/turtle> .

Web App Usage

Two simple web-apps exist to manage Standard Name Tables and to semantically enrich HDF5 files with Standard Names.

1. A Streamlit app to semantically enrich HDF5 files (requires hdf extra)
2. A Flask app to create and manage Standard Name Tables (requires app extra)

Install the library with the required extras:

pip install ssnolib[app,hdf]

To start the GUI:

ssnolib --h5sn

or

ssnolib --app

This will start a local development server at https://127.0.0.1:5000/.

Note: The web app is work in progress. Do not expose it to the public. Feedback and contributions are welcome!

Testing

To run tests:

pytest tests

Contribution

Contributions are welcome! Please open an issue or pull request. Guidelines:

• Write clear commit messages
• Add tests for new features
• Document changes in CHANGELOG.md

Citation

Please cite this project using the CITATION.cff.

License

This project is licensed under the MIT License.

Support & Contact

• Report issues: GitHub Issues
• Questions & feedback: matth.probst@gmail.com