Kafka Connect Solr for writing data to Solr. The SolrSinkTask can be configured with the following configuration.
solr.cluster.url=http://localhost:8983/solr/kafka-solr/update/json?commit=true
solr.cluster.name=kafka-solr-sink-sample
bulk.size=500
action.type=insert
solr.doc.converter=com.apache.kafka.connect.solr.converter.SolrJsonDocConverter
solr.doc.converter is a com.apache.kafka.connect.solr.converter.Converter that needs to be configured. This will take a SinkRecord object and serialize it in to JSON bytes that can be written to Solr.
If the data in Kafka is already in JSON format then you can use the com.apache.kafka.connect.solr.converter.SolrJsonDocConverter that is available with this library.
If the data in Kafka is in Avro format then you can use the com.apache.kafka.connect.solr.converter.SolrAvroJsonDocConverter that is available with this library.