Package org.apache.cassandra.cdc.schemastore

Class CachingSchemaStore

  • All Implemented Interfaces:
    SchemaStore
    public class CachingSchemaStore
extends java.lang.Object
implements SchemaStore
    Recommended implementation of SchemaStore that detects schema changes and regenerates Avro schema. Pass in a `SchemaStorePublisherFactory` to publish the schema downstream.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      org.apache.avro.generic.GenericDatumReader<org.apache.avro.generic.GenericRecord> getReader​(java.lang.String namespace, java.lang.String name)
      Get the datum reader
      org.apache.avro.Schema getSchema​(java.lang.String namespace, java.lang.String name)
      Get the avro corresponding to the namespace and the name of the schema
      java.util.Map<java.lang.String,​org.apache.avro.Schema> getSchemas()  
      java.lang.String getVersion​(java.lang.String namespace, java.lang.String name)
      Get the schema version corresponding to the namespace and the name of the schema
      org.apache.avro.generic.GenericDatumWriter<org.apache.avro.generic.GenericRecord> getWriter​(java.lang.String namespace, java.lang.String name)
      Get the datum writer
      void initialize()
      `initialize()` must be called on server start-up once all other dependencies are initialized, e.g.
      void onConfigChange()
      `onConfigChange()` should be called whenever the Kafka config is changed and the publisher needs to be rebuilt.
      void onSchemaChange()
      `onSchemaChanged()` should be called whenever a Cassandra CQL schema change is detected.
      protected org.apache.cassandra.cdc.avro.CqlToAvroSchemaConverter schemaConverter()  

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • CachingSchemaStore

        public CachingSchemaStore​(SchemaStoreStats schemaStoreStats,
                          java.util.function.Supplier<org.apache.cassandra.bridge.CassandraVersion> cassandraVersionSupplier,
                          org.apache.cassandra.cdc.api.SchemaSupplier schemaSupplier,
                          SchemaStorePublisherFactory schemaStorePublisherFactory,
                          KafkaOptions kafkaOptions)

    • Method Detail

      • initialize

        public void initialize()
        `initialize()` must be called on server start-up once all other dependencies are initialized, e.g. when Sidecar has fully initialized connections to Cassandra.

      • onConfigChange

        public void onConfigChange()
        `onConfigChange()` should be called whenever the Kafka config is changed and the publisher needs to be rebuilt.

      • onSchemaChange

        public void onSchemaChange()
        `onSchemaChanged()` should be called whenever a Cassandra CQL schema change is detected.

      • schemaConverter

        @NotNull
protected org.apache.cassandra.cdc.avro.CqlToAvroSchemaConverter schemaConverter()

      • getSchema

        public org.apache.avro.Schema getSchema​(java.lang.String namespace,
                                        java.lang.String name)
        Description copied from interface: SchemaStore
        Get the avro corresponding to the namespace and the name of the schema
        Specified by:
        getSchema in interface SchemaStore
        Returns:
        avro schema, or return null if nothing can be found

      • getWriter

        public org.apache.avro.generic.GenericDatumWriter<org.apache.avro.generic.GenericRecord> getWriter​(java.lang.String namespace,
                                                                                                   java.lang.String name)
        Description copied from interface: SchemaStore
        Get the datum writer
        Specified by:
        getWriter in interface SchemaStore
        Returns:
        datum writer or null if schema is not found

      • getReader

        public org.apache.avro.generic.GenericDatumReader<org.apache.avro.generic.GenericRecord> getReader​(java.lang.String namespace,
                                                                                                   java.lang.String name)
        Description copied from interface: SchemaStore
        Get the datum reader
        Specified by:
        getReader in interface SchemaStore
        Returns:
        datum reader or null if schema is not found

      • getVersion

        public java.lang.String getVersion​(java.lang.String namespace,
                                   java.lang.String name)
        Description copied from interface: SchemaStore
        Get the schema version corresponding to the namespace and the name of the schema
        Specified by:
        getVersion in interface SchemaStore
        Returns:
        a type 3 (name based) UUID generated based on the MD5 of the CQL schema, or return null if nothing can be found

      • getSchemas

        public java.util.Map<java.lang.String,​org.apache.avro.Schema> getSchemas()