Input Parameters
Description
The input content sent to OpenCalais is accompanied by a set of parameters (in XML format) that includes processing directives, user directives and external metadata. Please note that paramsXML are case-sensitive and must be HTTP encoded (escaped).
The input parameters for the API call are summarized here:
| Parameter | Section | Definition | Values | Default |
| contentType | Processing Directives | Format of the input content (see details below) | "TEXT/XML" "TEXT/HTML" "TEXT/HTMLRAW" "TEXT/RAW" |
(none) |
| outputFormat | Processing Directives | Format of the returned results |
"XML/RDF", "Text/Simple" or "Text/Microformats" or "Application/JSON" |
XML/RDF |
| reltagBaseURL | Processing Directives | Base URL to be put in rel-tag microformats | <the base URL>, for example "http://myblog.com/tag" | (none) |
| calculateRelevanceScore | Processing Directives | Indicates whether the extracted metadata will include relevance score for each unique entity | "true" or "false" | true |
| enableMetadataType | Processing Directives | Indicates whether output will include Generic Relation extractions (RDF) and/or SocialTags | "GenericRelations" - to enable Generic Relations; "SocialTags" - to enable Social Tags (could combine comma-separated options: "GenericRelations,SocialTags" |
(none) |
| docRDFaccessible | Processing Directives | Indicates whether entire XML/RDF document is saved in the Calais Linked Data repository | "true" or "false" | (none) |
| allowDistribution | User Directives | Indicates whether the extracted metadata can be distributed | "true" or "false" | false |
| allowSearch | User Directives | Indicates whether future searches can be performed on the extracted metadata | "true" or "false" | false |
| externalID | User Directives | User-generated ID for the submission | any string | (none) |
| submitter | User Directives | Identifier for the content submitter | any string | (none) |
In addition, users can add external metadata that will be returned in the response. This can be done by embedding an RDF representation of the user's metadata in the externalMetadata node. Please be sure to embed RDF-compliant metadata (will be supported in future versions).
Check the example in the next section that shows how the parameters XML should look. Of course, you may change the parameter values and the user's external metadata as explained above.
Please note that paramsXML must start with the root element "<c:params>" ("c" can be replaced with any other prefix but the namespace must still be "http://s.opencalais.com/1/pred").
Example Parameter File
<c:params xmlns:c="http://s.opencalais.com/1/pred/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<c:processingDirectives c:contentType="text/txt" c:enableMetadataType="GenericRelations" c:outputFormat="xml/rdf" c:docRDFaccesible="true" >
</c:processingDirectives>
<c:userDirectives c:allowDistribution="true" c:allowSearch="true" c:externalID="17cabs901" c:submitter="ABC">
</c:userDirectives>
<c:externalMetadata>
</c:externalMetadata>
</c:params>
