action

Action

An action is something that can be performed by an actor. An action can trigger a state transition and/or may update the process variables.

{% tabs %} {% tab title="YAML" %}

issue:
 title: Issue new license
 actor: issuer
 if: !ref vars.license == null
 update:
   set: vars.license

{% endtab %}

{% tab title="JSON" %}

{
  "issue": {
    "$schema": "https://specs.letsflow.io/v0.2.0/action/schema.json",
    "actor": "issuer",
    "responses": {
      "ok": {
        "title": "Issued new license",
        "update": [
          {
            "select": "assets.license"
          },
          {
            "select": "assets.available",
            "projection": "{shipments: shipments, quantity: quantity}"
          }
        ]
      }
    }
  }
}

{% endtab %} {% endtabs %}

JSON Schema

https://schemas.letsflow.io/v1.0/action

Action

$schema

URI

The action JSON schema URI that describes the JSON structure of the action. This can also be used for automation and may be used by the UI.

title

string

A short title for the action.

description

string or function

A long description of the action that is shown when the action has been performed.

actor

string, data function, or array of strings and/or data functions

Defines the actor allowed to perform this action.

• If a single actor is permitted, specify their key.
• If multiple actors can perform the action, use an array.
• To allow all actors in the schema, use an asterisk (*).
• Wildcard actors (keys ending in *) are also supported.

To assign the action to a service, set the actor to service:SERVICE_NAME. Note that the asterisk (*) does not apply to services.

if

boolean or function

This field must be true for the action to be allowed to be executed. Typically used in combination with a <ref> data function.

response

schema

Define the data type of the response data of the action using a JSON schema.

stub

any

The response value that is used when predicting the next states.

update

update instruction or array of update instructions

Update instructions are used to update the process variables after executing an action.

{% content-ref url="update-instruction.md" %} update-instruction.md {% endcontent-ref %}