Search Management

Example Code

Search Master

Introduction

The SearchMasterService is the main entry point to the functionality of the search engine. It contains the elements that will organize the execution of the search operators for the various tasks the Search engine is responsible for.

The SearchMasterService is responsible for the first stage of query processing. This stage produces a query execution plan, which in the DILIGENT implementation is a directed acyclic graph of SearchOperator invocations. This element is responsible for gathering the whole set of information that is expected to be needed by the various search services and provides it as context to the processed query. In this manner, delays for gathering info at the various services are significantly reduced and assist responsiveness.

The information gathered is produced by various components or services of the DILIGENT Infrastructure. They include the Diligent Information Service (DIS), Content and Metadata Management, Indexing service etc. The process of gathering all needed information proves to be very time consuming. To this end, the SearchMasterService keeps a cache of previously discovered information and state.

The SearchMaster validates the received Query using Search Library elements. It validates the user supplied query against the elements of the specific Digital Library Instance. This ensures that content collections are available, metadata elements (e.g. fields) are present, operators (i.e. services) are accessible etc.

DL Description

Through the Search Master, external services can receive a structured overview of the Digital Library resources available and usable during a search operation. An example of this summarization is shown bellow:

  <SearchConfig>
    <collections>
      <collection name="Example Collection Name 1" id="1fc1fbf0-fa3c-11db-82de-905c553f17c3">
        <TYPE>DATA</TYPE>
        <ASSOCIATEDWITH>d510a060-fa3c-11db-aa91-f715cb72c9ff</ASSOCIATEDWITH>
        <ASSOCIATEDWITH>g45612f7-dth5-23fg-45df-45dfg5b1r34s</ASSOCIATEDWITH>
      </collection>
      <collection name="Example Collection Name 2" id="c3f685b0-fdb6-11db-a573-e4518f2111ab">
        <TYPE>DATA</TYPE>
        <ASSOCIATEDWITH>7bb87410-fdb7-11db-8476-f715cb72c9ff</ASSOCIATEDWITH>
        <INDEX>FEATURE</INDEX>
      </collection>
      <collection name="Example Collection Name 3" id="d510a060-fa3c-11db-aa91-f715cb72c9ff">
        <TYPE>METADATA</TYPE>
        <LANGUAGE>en</LANGUAGE>
        <SCHEMA>dc</SCHEMA>
        <ASSOCIATEDWITH>1fc1fbf0-fa3c-11db-82de-905c553f17c3</ASSOCIATEDWITH>
        <INDEX>FTS</INDEX>
        <INDEX>XML</INDEX>
      </collection>
      <collection name="Example Collection Name 4" id="g45612f7-dth5-23fg-45df-45dfg5b1r34s">
        <TYPE>METADATA</TYPE>
        <LANGUAGE>en</LANGUAGE>
        <SCHEMA>tei</SCHEMA>
        <ASSOCIATEDWITH>1fc1fbf0-fa3c-11db-82de-905c553f17c3</ASSOCIATEDWITH>
        <INDEX>FTS</INDEX>
        <INDEX>XML</INDEX>
      </collection>
      <collection name="Example Collection Name 5" id="7bb87410-fdb7-11db-8476-f715cb72c9ff">
        <TYPE>METADATA</TYPE>
        <LANGUAGE>en</LANGUAGE>
        <SCHEMA>dc</SCHEMA>
        <ASSOCIATEDWITH>c3f685b0-fdb6-11db-a573-e4518f2111ab</ASSOCIATEDWITH>
        <INDEX>FTS</INDEX>
        <INDEX>XML</INDEX>
      </collection>
    </collections>
  </SearchConfig>

Search Management

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