GS2-StateMachine Transaction Actions

Specification of verify/consume/acquire transaction actions

Combining actions, and concurrency

The background common to every service is collected in Combining Transaction Actions. Read that first; the rest of this section is what GS2-StateMachine adds to it.

GS2-StateMachine provides one transaction action. Starting a state machine creates a new status every time, so it never competes with anything for a target.

Operation	Repeated in one transaction	Across a nested transaction	Boundary that separates targets
Starting a state machine `StartStateMachineByUserId`	Each one starts its own state machine; they never collide	No collision	every start is its own target

Each step of a running state machine is a transaction of its own as well, so it is never combined with the transaction that started it. What a state machine does inside those steps is subject to the restrictions of whichever services it touches.

Take care with nested transactions

Starting a state machine is unaffected, because every start creates its own status. The steps that follow are separate transactions, so they are not combined with the one that started them either.

Concurrency and retries

GS2-StateMachine does not return a conflict of its own when state machines are started concurrently. Whether the steps conflict is decided by what they write, and the retry guidance of those services applies.

Acquire Action

Gs2StateMachine:StartStateMachineByUserId

Start state machine by User ID

Starts a new state machine instance for the specified user using the latest master version. Arguments are passed as JSON and parsed into state machine variables. An optional TTL (in minutes) can be set; if omitted, the state machine remains valid for approximately 10 years.

Quantity specification supported: NO

Reversible action: NO

	Type	Required	Default	Value Limits	Description
namespaceName	string	✓		~ 128 chars	Namespace name Unique Namespace name. Specified using alphanumeric characters, hyphens (-), underscores (_), and periods (.).
userId	string	✓		~ 128 chars	User ID Specify `#{userId}` to substitute the currently logged-in user’s ID.
args	string		“{}”	~ 4096 chars	Arguments to be passed to the state machine
ttl	int			1 ~ 525600	Validity period (minutes)
timeOffsetToken	string			~ 1024 chars	Time offset token

{
    "action": "Gs2StateMachine:StartStateMachineByUserId",
    "request": {
        "namespaceName": "[string]Namespace name",
        "userId": "[string]User ID",
        "args": "[string]Arguments to be passed to the state machine",
        "ttl": "[int]Validity period (minutes)",
        "timeOffsetToken": "[string]Time offset token"
    }
}

action: Gs2StateMachine:StartStateMachineByUserId
request:
  namespaceName: "[string]Namespace name"
  userId: "[string]User ID"
  args: "[string]Arguments to be passed to the state machine"
  ttl: "[int]Validity period (minutes)"
  timeOffsetToken: "[string]Time offset token"

transaction.service("stateMachine").acquire.start_state_machine_by_user_id({
    namespaceName="[string]Namespace name",
    userId="[string]User ID",
    args="[string]Arguments to be passed to the state machine",
    ttl="[int]Validity period (minutes)",
    timeOffsetToken="[string]Time offset token",
})