Initial projections in continuous schedule

[bounoable]

A complex continuous projection job may creates a projection target that needs all of the past events in order to fully build the projection state. Currently, when a continuous projection schedule triggers, only the events that triggered the schedule in that moment are applied "continuously" to the projections. A projection must be able to hint to the projection job that it needs the full event history for the initial run.

package example

type Foo struct {
  valid bool
}

func (f *Foo) ApplyEvent(e event.Event) {
  switch e.Name {
    case "initialized":
      f.valid = true
    case "changed":
      if !f.valid {
        panic("not allowed")
      }
  }
}

func (f *Foo) RequiresFullHistory() bool {
  return !f.valid
}