drb-metadata 1.3.2

DRB Metadata Extractor

DRB Metadata Extractor

It's an applicative part using DRB allowing to extract metadata from data according its topic.

Metadata

How to extract metadata ?

from drb.metadata import MetadataAddon
import drb.topics.resolver as resolver


if __name__ == '__main__':
    topic, node = resolver.resolve('<my_resource_url>')
    # topic keyword argument is not mandatory
    metadata = MetadataAddon().apply(node, topic=topic)
    for md_name, md in metadata.items():
        print(md_name, ' -- ', md.extract())

How to define metadata ?

Metadata are defined in a cortex.yaml file following the template:

drbItemClass: <topic_uuid>           # target topic
variables:                           # variable list
  - name: <var_name>                   # variable name
    <extractor>: <extractor_content>   # an extractor
metadata:                            # metadata list
  - name: my_metadata                  # metadata name
    <extractor>: <extractor_content>   # an extractor

• metadata are applied to their target topic and its derivatives
• inherited metadata is override if it's redefined in a derivative topic
• variables are not transitive between a topic and its derivatives

Packaging

The package python containing metadata of a DRB topic must have the following instruction:

• a drb.metadata entry point whose its value is the targeted Python package containing the cortex.yaml file