@Override
    public String getSchema(SystemStream systemStream) {
      return config.get(String.format(CFG_SOURCE_SCHEMA, systemStream.getSystem(), systemStream.getStream()));
    }
Avro Schema Resolver that uses static config to return a schema for a SystemStream.
Schemas are configured using the config of format {systemName}.{streamName}.schema.
samza-sql/src/main/java/org/apache/samza/sql/avro/ConfigBasedAvroRelSchemaProviderFactory.java