Index Pipeline Stages

An Index Pipeline takes content and transforms it into a document suitable for indexing by Solr via a series of modularized operations called stages. The objects sent from stage to stage are PipelineDocument objects. Fusion provides many specialized index stages as well as a Javascript Index stage that allows for custom processing via a JavaScript program.The general outline of theExtract/Transform/Load processing performed by an index pipeline is:

  • Raw content is parsed into one or more PipelineDocument objects.

  • Any number of intermediate stages operate on the document fields directly, or, in the case of specialized NLP tools, add annotations to a document.

  • Finally, the PipelineDocument is sent to Solr for indexing.

A pipeline stage definition associates a unique ID with a set of properties. Pipeline definitions are stored in ZooKeeper for reuse across pipelines and search applications. The Fusion UI provides stage-specific panels used to define and configure each pipeline stage. Alternatively, JSON can be used to specify the sequence of pipeline stages and registered via the Fusion REST-API. Some stages require additional resources, e.g., text files which contain lists of names, synonyms, places, or binary files which NLP language models. These resources can be uploaded via the Fusion UI or the REST-API.

Available index pipeline stages are listed below: