OpenCalais metadata extraction in Elvis

Open Calais is a Web Service which processes submitted text and returns entities, topic codes, events, relations and social tags.

This service can be integrated in Elvis so that Open Calais metadata fields are automatically populated for an asset.

Note: For an overview of the available fields, see Metadata field information for Elvis 5.

Figure: Open Calais metadata fields populated for a text file.

How it works

This feature works when an asset is imported into Elvis. During this process, the textual content is sent to Open Calais where it is analyzed. The values that are generated by Open Calais are received by Elvis and automatically added to the Open Calais metadata fields in Elvis.

This process is fully automatic and requires no manual steps by the user.

Assets for which this feature can be used

This feature only works for assets that have textual content:

• Text files and documents
• HTML files
• PDFs

Configuration

To enable Open Calais for assets stored in Elvis, do the following:

Step 1. Request an Open Calais API key by visiting the Calais Tagging Quick Start Guide and following the instructions.

Step 2. Add the key to the cluster-config.properties.txt file:

For information about editing this file, see Changing the Elvis 5 Server configuration for a running cluster.

openCalaisAPIKey=yourAPIkey

Step 3. Restart Elvis Server.

Document history

• 4 October 2018: Updated references related to Open Calais.