Core Configuration

WowProperties

• Configuration class: WowProperties
• Prefix: wow

Name	Data Type	Description	Default Value
enabled	Boolean	Enable/disable the Wow framework	true
context-name	String	Bounded context name for the service	Falls back to (required) spring.application.name
shutdown-timeout	Duration	Global deadline for quiescing and stopping the complete Wow runtime	60s
shutdown-quiet-period	Duration	Stable idle period required before dispatcher intake closes; new activity resets it	1s

shutdown-timeout must be positive. shutdown-quiet-period must be non-negative and strictly shorter than shutdown-timeout. Both durations must fit in a signed 64-bit nanosecond value.

wow:
  enabled: true
  context-name: order-service
  shutdown-timeout: 120s
  shutdown-quiet-period: 2s

BusProperties

BusProperties is the shared configuration for CommandBus, EventBus, and StateEventBus.

• Configuration class: BusProperties

Name	Data Type	Description	Default Value
type	BusType	Message bus implementation type	kafka
local-first	LocalFirstProperties	LocalFirst mode configuration

BusType

enum class BusType {
    KAFKA,      // Apache Kafka (recommended for production)
    REDIS,      // Redis Streams
    IN_MEMORY,  // In-memory (for testing)
    NO_OP;      // No-op (for special cases)
}

LocalFirst Mode

LocalFirst mode first attempts local runtime admission while always sending a distributed copy. The copy is marked locally handled only after every targeted local receiver accepts admission; otherwise it remains eligible for distributed processing.

Behavior and failure boundary

1. Reduced latency: locally admitted messages avoid a broker round trip before processing.
2. Admission-aware fallback: no subscriber, closed processing, or local-send failure leaves the distributed copy eligible for processing.
3. No retroactive reroute: after local admission succeeds, a later handler failure follows the normal handler retry and acknowledgement policy; it does not re-enable the distributed copy.

Source: LocalFirstMessageBus.

Name	Data Type	Description	Default Value
local-first.enabled	Boolean	Enable LocalFirst mode	true

Command Bus

• Configuration class: CommandProperties
• Prefix: wow.command.

Name	Data Type	Description	Default Value
bus	BusProperties	Command bus configuration
idempotency	IdempotencyProperties	Command idempotency

wow:
  command:
    bus:
      type: kafka
      local-first:
        enabled: true
    idempotency:
      enabled: true
      bloom-filter:
        expected-insertions: 1000000
        ttl: PT60S
        fpp: 0.00001

IdempotencyProperties

• Configuration class: IdempotencyProperties

Name	Data Type	Description	Default Value
enabled	boolean	Whether to enable	true
bloom-filter	BloomFilter	BloomFilter

BloomFilter

Name	Data Type	Description	Default Value
ttl	Duration	Time to live	Duration.ofMinutes(1)
expected-insertions	Long	Expected number of insertions	1000_000
fpp	Double	False positive probability	0.00001

Event Bus

• Configuration class: EventProperties
• Prefix: wow.event.

Name	Data Type	Description	Default Value
bus	BusProperties	Event bus configuration

wow:
  event:
    bus:
      type: kafka
      local-first:
        enabled: true

Event Sourcing

EventStoreProperties

• Configuration class: EventStoreProperties
• Prefix: wow.eventsourcing.store

Name	Data Type	Description	Default Value
storage	StorageType	Event store storage backend	mongo

wow:
  eventsourcing:
    store:
      storage: mongo

StorageType

The StorageType enum is shared across the event store and snapshot store.

enum class StorageType {
    MONGO,
    REDIS,
    ELASTICSEARCH,
    IN_MEMORY,
    DELAY
    ;
}

SnapshotProperties

• Configuration class: SnapshotProperties
• Prefix: wow.eventsourcing.snapshot

Name	Data Type	Description	Default Value
enabled	Boolean	Whether to enable snapshots	true
strategy	Strategy	Snapshot strategy	all
version-offset	Int	Version offset threshold	5
storage	StorageType	Snapshot storage backend	mongo

wow:
  eventsourcing:
    snapshot:
      enabled: true
      strategy: all
      storage: mongo

Strategy

enum class Strategy {
    ALL,
    VERSION_OFFSET,
    ;
}

The snapshot storage property reuses the shared StorageType enum.

StorageRoutingProperties

Route different aggregates to different storage backends within a single service. When a matching route is configured, Wow installs a RoutingEventStore / RoutingSnapshotStore that dispatches per aggregate to the bound store, falling back to the default storage (wow.eventsourcing.store.storage / wow.eventsourcing.snapshot.storage) for unlisted aggregates.

• Configuration class: StorageRoutingProperties
• Prefix: wow.eventsourcing.storage-routing

Name	Data Type	Description	Default Value
aggregates	Map<String, AggregateStorageRouteProperties>	Per-aggregate route keyed by aggregate name	{} (empty)

Each aggregate route accepts an event and/or snapshot channel. A configured channel must set exactly one of storage or binding — an empty channel (e.g. event: {}) fails fast at startup. Omitting a channel entirely is what falls back to the default store.

Name	Data Type	Description	Default Value
storage	StorageType	Storage backend for this channel (overrides the default)	(required if binding absent)
binding	String	Name of the bound store/query-service bean to use	(required if storage absent)

wow:
  eventsourcing:
    storage-routing:
      aggregates:
        # Hot aggregate: keep events and snapshots in Redis for low latency
        HotAggregate:
          event:
            storage: redis
          snapshot:
            storage: redis
        # Cold aggregate: fall back to the default MongoDB store
        # (no route entry needed — default applies)

State Event Bus

• Configuration class: StateProperties
• Prefix: wow.eventsourcing.state

Name	Data Type	Description	Default Value
bus	BusProperties	State event bus configuration

wow:
  eventsourcing:
    state:
      bus:
        type: kafka
        local-first:
          enabled: true

Prepare Key

• Prefix: wow.prepare

Name	Data Type	Description	Default Value
enabled	Boolean	Enable PrepareKey functionality	true
storage	PrepareStorage	Storage backend for PrepareKey	MONGO
base-packages	List<String>	Base packages to scan for PrepareKey definitions	[]

PrepareStorage Values

Value	Description
MONGO	MongoDB (recommended)
REDIS	Redis

wow:
  prepare:
    enabled: true
    storage: mongo
    base-packages:
      - com.example.domain

Environment-Specific Configuration

Development Environment

wow:
  command:
    bus:
      type: in_memory
  event:
    bus:
      type: in_memory
  eventsourcing:
    store:
      storage: in_memory
    snapshot:
      storage: in_memory

Production Environment

wow:
  command:
    bus:
      type: kafka
      local-first:
        enabled: true
  event:
    bus:
      type: kafka
      local-first:
        enabled: true
  eventsourcing:
    store:
      storage: mongo
    snapshot:
      enabled: true
      strategy: all
      storage: mongo

Complete Configuration Example

spring:
  application:
    name: order-service

wow:
  enabled: true
  context-name: order-service
  shutdown-timeout: 120s
  shutdown-quiet-period: 2s

  command:
    bus:
      type: kafka
      local-first:
        enabled: true

  event:
    bus:
      type: kafka
      local-first:
        enabled: true

  eventsourcing:
    store:
      storage: mongo
    snapshot:
      enabled: true
      strategy: all
      storage: mongo
    state:
      bus:
        type: kafka
        local-first:
          enabled: true

  kafka:
    bootstrap-servers:
      - kafka-0:9092
      - kafka-1:9092
      - kafka-2:9092
    topic-prefix: 'wow.'

  mongo:
    enabled: true
    auto-init-schema: true

  openapi:
    enabled: true

  webflux:
    enabled: true
    global-error:
      enabled: true