KEFCore: KafkaDbContext

KafkaDbContext is a special class which helps to define the DbContext and use Entity Framework Core provider for Apache Kafka™:

KafkaDbContext inherits from DbContext: to define the model, and/or creating the database, see getting started in the docs and KEFCore usage
KafkaDbContext defines the following properties:
- KeySerDesSelectorType: the .NET type to be used to allocate an external serializer for Apache Kafka™ record key
- ValueSerDesSelectorType: the .NET type to be used to allocate an external serializer for Apache Kafka™ record value
- ValueContainerType: the .NET type to be used to allocate an external container class for Apache Kafka™ record value
- UseNameMatching: set to false to avoid Entity matching based on Name
- BootstrapServers: the server hosting the broker of Apache Kafka™
- ApplicationId: the application identifier used to identify the context
- DatabaseName: the user defined name which declares the database name, it is used to prepend every Topic which belongs to this database
- DefaultNumPartitions: the default number of partitions used when topics are created for each entity
- DefaultReplicationFactor: the replication factor to use when data are stored in Apache Kafka™
- DefaultConsumerInstances: the consumer instances to be allocated when UseCompactedReplicator is true
- UsePersistentStorage: set to true to use a persistent storage between multiple application startup
- UseEnumeratorWithPrefetch: set to true to prefer enumerator instances able to do a prefetch on data speeding up execution, used if UseKNetStreams is true and UseCompactedReplicator is false
- UseByteBufferDataTransfer: set to true to prefer data exchange in serializer instances
- UseDeletePolicyForTopic: set to true to enable delete cleanup policy
- UseCompactedReplicator: Use KNetCompactedReplicator instead of Apache Kafka™ Streams to manage data to or from topics
- UseKNetStreams: Use KNet version of Apache Kafka™ Streams instead of standard Apache Kafka™ Streams, used if UseCompactedReplicator is false
- ConsumerConfig: parameters to use for Producer
- ProducerConfig: parameters to use for Producer
- StreamsConfig: parameters to use for Apche Kafka™ Streams application
- TopicConfig: parameters to use on topic creation for each entity
- OnChangeEvent: handler to receive change events from back-end

How to use `KafkaDbContext` class

The most simple example of usage can be found in KEFCore usage. By default, KafkaDbContext automatically manages OnConfiguring method of DbContext:

KafkaDbContext checks the mandatory options like BootstrapServers and DbName
KafkaDbContext setup the options needed to use an Apache Kafka™ cluster:
- default ConsumerConfig can be overridden using ConsumerConfig property of KafkaDbContext
- default ProducerConfig can be overridden using ProducerConfig property of KafkaDbContext
- default StreamsConfig can be overridden using StreamsConfig property of KafkaDbContext
- default TopicConfig can be overridden using TopicConfig property of KafkaDbContext

Default ConsumerConfig

Over the Apache Kafka™ defaults it applies:

EnableAutoCommit is true
AutoOffsetReset set to EARLIEST
AllowAutoCreateTopics set to false

Default ProducerConfig

Does not change anything over the Apache Kafka™ defaults

Default StreamsConfig