Version 0.6.0 Released - Occurrent - Event Sourcing Utilities for the JVM

Occurrent 0.6.0 is now available. It mainly focuses on reliability improvements to several components to prepare them for production use. Specifically, all blocking subscriptions and subscription position storage modules, now have defaults to retrying failed operations to the datastore and your event handling methods. Retries can be controlled, and disabled, when creating the component (by passing RetryStrategy.none() to the constructor). It’s fine to disable the default retry strategy for a subscription model and handle it in the action (event callback) instead if you want to make it explicit.

Changes are:

Renamed method shutdownSubscribers in DurableSubscriptonModel to shutdown.
Added default subscription name to subscription DSL. You can now do:
```
  subscriptions(subscriptionModel) {
      subscribe<NameDefined> { e ->
          log.info("Hello ${e.name}")
      }
  }
```
The id of the subscription will be “NameDefine” (the unqualified name of the NameDefined class).
Added exists method to EventStoreQueries API (both blocking and reactive). This means that you can easily check if events exists, for example:
```
  val doesSomeTypeExists = eventStoreQueries.exists(type("sometype"))
```
Added retry strategy support to SpringMongoSubscriptionPositionStorage. You can define your own by passing an instance of RetryStrategy to the constructor. By default it’ll add a retry strategy with exponential backoff starting with 100 ms and progressively go up to max 2 seconds wait time between each retry when reading/saving/deleting the subscription position.
Added retry strategy support to NativeMongoSubscriptionPositionStorage. You can define your own by passing an instance of RetryStrategy to the constructor. By default it’ll add a retry strategy with exponential backoff starting with 100 ms and progressively go up to max 2 seconds wait time between each retry when reading/saving/deleting the subscription position.
Added retry strategy support to SpringRedisSubscriptionPositionStorage. You can define your own by passing an instance of RetryStrategy to the constructor. By default it’ll add a retry strategy with exponential backoff starting with 100 ms and progressively go up to max 2 seconds wait time between each retry when reading/saving/deleting the subscription position.
Added retry strategy support to SpringMongoSubscriptionModel. You can define your own by passing an instance of RetryStrategy to the constructor. By default it’ll add a retry strategy with exponential backoff starting with 100 ms and progressively go up to max 2 seconds wait time between each retry when exceptions are thrown from the action callback (the callback that you implement to handle a CloudEvent instance from a subscription).
All blocking subscription models will throw an IllegalArgumentException if a subscription is registered more than once.

Occurrent 0.6.0 released