How to import Stack Exchange Data into Apache Solr

The Apache Solr platform is a popular, blazing-fast, open source enterprise search solution built on Apache Lucene.

Apache Solr is equipped with the Data Import Handler (DIH), which can import data from databases and, XML, CSV, and JSON files. When paired with the CData JDBC Driver for Stack Exchange, you can easily import Stack Exchange data to Apache Solr. In this article, we show step-by-step how to use CData JDBC Driver in Apache Solr Data Import Handler and import Stack Exchange data for use in enterprise search.

Create an Apache Solr Core and a Schema for Importing Stack Exchange

1. Run Apache Solr and create a Core.

   > solr create -c CDataCore

   For this article, Solr is running as a standalone instance in the local environment and you can access the core at this URL: http://localhost:8983/solr/#/CDataCore/core-overview
2. Create a schema consisting of "field" objects to represent the columns of the Stack Exchange data to be imported and a unique key for the entity. LastModifiedDate, if it exists in Stack Exchange, is used for incremental updates. If it does not exist, you cannot do the deltaquery in the later section. Save the schema in the managed-schema file created by Apache Solr.

	APIUniqueKey
	
	
	
	
	
	
	
	   
	


3. Install the CData Stack Exchange JDBC Driver. Copy the JAR and license file (cdata.api.jar and cdata.jdbc.api.lic) to the Solr directory.
   
   • CData JDBC JAR file: C:\Program Files\CData\CData JDBC Driver for Stack Exchange ####\lib
   • Apache Solr: solr-8.5.2\server\lib

Now we are ready to use Stack Exchange data in Solr.

Define an Import of Stack Exchange to Apache Solr

In this section, we walk through configuring the Data Import Handler.

1. Modify the Config file of the created Core. Add the JAR file reference and add the DIH RequestHander definition.

   	
   
   	<lib dir="${solr.install.dir:../../../..}/dist/" regex="solr-dataimporthandler-.*\.jar" />
   
   	<requestHandler name="/dataimport" class="org.apache.solr.handler.dataimport.DataImportHandler">
   		<lst name="defaults">
   			<str name="config">solr-data-config.xml</str>
   		</lst>
   	</requestHandler>

2. Next, create a solr-data-config.xml at the same level. In this article, we retrieve a table from Stack Exchange, but you can use a custom SQL query to request data as well. The Driver Class and a sample JDBC Connection string are in the sample code below.

   	
   	<dataConfig>
   		<dataSource driver="cdata.jdbc.api.APIDriver" url="jdbc:api:Profile=C:\profiles\StackExchange.apip;ProfileSettings='APIKey=your_api_key;Site=stackoverflow';">
   		</dataSource> 
   		<document> 
   			<entity name="Answers" 
   				query="SELECT Id,APIColumn1,APIColumn2,APIColumn3,APIColumn4,APIColumn5,APIColumn6,APIColumn7,LastModifiedDate FROM Answers"
   				deltaQuery="SELECT Id FROM Answers where LastModifiedDate >= '${dataimporter.last_index_time}'"
   				deltaImportQuery="SELECT Id,APIColumn1,APIColumn2,APIColumn3,APIColumn4,APIColumn5,APIColumn6,APIColumn7,LastModifiedDate FROM Answers where Id=${dataimporter.delta.Id}">
   				<field column="Id" name="Id" ></field>
   				<field column="APIColumn1" name="APIColumn1" ></field>
   				<field column="APIColumn2" name="APIColumn2" ></field>
   				<field column="APIColumn3" name="APIColumn3" ></field>
   				<field column="APIColumn4" name="APIColumn4" ></field>
   				<field column="APIColumn5" name="APIColumn5" ></field>
   				<field column="APIColumn6" name="APIColumn6" ></field>
   				<field column="APIColumn7" name="APIColumn7" ></field>
   				<field column="LastModifiedDate" name="LastModifiedDate" ></field>   
   			</entity>
   		</document>
   	</dataConfig>

3. In the query section, set the SQL query that select the data from Stack Exchange. deltaQuery and deltaImportquery define the ID and the conditions when using incremental updates from the second import of the same entity.
4. After all settings are done, restart Solr.

   	> solr stop -all
   	> solr start
   	

Run a DataImport of Stack Exchange Data.

1. Execute DataImport from the URL below:
   http://localhost:8983/solr/#/CDataCore/dataimport//dataimport
2. Select the "full-import" Command, choose the table from Entity, and click "Execute."
3. Check the result of the import from the Query.
4. Try an incremental update using deltaQuery. Modify some data in the original Stack Exchange data set. Select the "delta-import" command this time from DataImport window and click "Execute."
5. Check the result of the incremental update.

Using the CData JDBC Driver for Stack Exchange you are able to create an automated import of Stack Exchange data into Apache Solr. Download a free, 30 day trial of any of the hundreds of CData JDBC Drivers and get started today.