ddd-ts-kit/process-sends-commands-only

Architecture id: process/sends-commands-only. Default severity: error in recommended, error in strict.

Applies to: application/processes/*.process.ts of a context, specs aside.

Why

A process manager coordinates a long-running process: it reacts to events, keeps a state of its own and decides what happens next. When it also loads and saves aggregates, it becomes a use case nobody can send, with no permission, no audit and a transaction that spans what it should only coordinate; when it writes the aggregate of another context, the boundary is gone. Its steps answer a decision, and the commands of that decision do the work, each in its own handler.

Reported

An import, in a process file, of:

• domain/aggregates/, domain/entities/, domain/repositories/ or domain/services/ of any context
• application/ports/ of any context
• infrastructure/ of any context

Incorrect:

import { ReminderRepository } from '@/contexts/notification/domain/repositories/reminder.repository';

export class AppointmentReminderProcess { /* saves reminders itself */ }

Correct:

import { PlanReminderCommand } from '@/contexts/notification/application/commands/plan-reminder/plan-reminder.command';

export class AppointmentReminderProcess implements ProcessManager<ReminderProcessState> {
  booked(event: AppointmentBookedV1, current: ReminderProcessState | undefined): ProcessDecision<ReminderProcessState> | undefined {
    return { state: { appointmentId: event.payload.appointmentId, stage: 'waiting' }, commands: [new PlanReminderCommand(/* ... */)] };
  }
}

Details

Commands, the published language of upstream contexts, value objects, vocabularies and the kernel stay allowed: a process builds commands and reads events.

Options

None.

rules."process/sends-commands-only" in ddd-ts-kit.config.json set to off silences the rule, and // ddd-ts-kit-disable-next-line process/sends-commands-only -- <reason> silences one line, exactly as for ddd-ts-kit check.

Limits

• An import read by a dynamic expression is not followed.

With the CLI checker

ddd-ts-kit check reports the same id from the text of the files.