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PersistenceId

Unique stable identity for a persistent actor — the primary key used by every event store and state store.

What it does​

PersistenceId combines an entity type (e.g. "Order") and an entity ID (e.g. "order-42") into a single canonical string "Order|order-42". The pipe separator is forbidden inside the entity type to guarantee unambiguous round-trip parsing via fromString(). All event-store and state-store operations use the persistence ID as their primary key, so the value must be stable across restarts — use domain entity UUIDs or slugs, not database auto-increment integers that could be re-assigned. Two PersistenceId instances are equal when both parts match, checked via equals() or by comparing the __toString() output directly.

Example​

src/OrderActor.php
use Monadial\Nexus\Persistence\PersistenceId;

// Construct from parts — the typical case
$id = PersistenceId::of('Order', $orderId);
echo $id;           // "Order|order-42"
echo $id->entityType; // "Order"
echo $id->entityId;   // "order-42"

// Round-trip from a stored string (e.g. read from a database column)
$restored = PersistenceId::fromString('Order|order-42');
$id->equals($restored); // true

// Pass to a behavior builder
$behavior = EventSourcedBehavior::create($id, new OrderState(), $cmdHandler, $evtHandler)
    ->withEventStore($eventStore)
    ->toBehavior();

Key methods​

  • PersistenceId::of(string $entityType, string $entityId): self — construct from separate parts; throws InvalidArgumentException if either is empty or if $entityType contains |.
  • PersistenceId::fromString(string $value): self — parse the canonical "EntityType|entityId" form; throws if no pipe is present.
  • toString(): string — returns "EntityType|entityId"; also called implicitly by string casts via __toString().
  • equals(PersistenceId $other): bool — value equality check on both parts.
  • $id->entityType / $id->entityId — readonly public properties for direct access without a method call.

Full API reference​

Full method list and class hierarchy

See also​