AggregateId

The property of a command that holds the id of the aggregate the command acts on, its target: a String the command's class declares, or an interface it implements does, stored or computed from other properties. The compiler generates its read, and the Manifest names it (idProperty), so:

• the command's routes name no id (POST /{context}/{aggregate}/{command}): the request names its aggregate in its body, and one that names it elsewhere as well (a ref beside the body) names the same one, or is malformed;

• a saga, a client or another context sends it without an id, which its body gives;

• a command that creates its aggregate may leave it null: the aggregate's id is then generated, as for any creation that names none; a blank id is malformed.

The id is in the body every sender writes: the property is one Wow's JSON writes, not @JsonIgnored. A sender that sends some properties alone (a form, a console) may leave a computed one out: the service computes it from the command. One property of a command is its aggregate id; an aggregate whose id is its owner's (@AggregateRoot(idSource = OWNER)) takes none, and neither does an @Unaddressed or a mounted command, whose transformer finds the aggregate.