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Please be sure to have reviewed the terminology before reviewing the service documentation below.
Each service object must contain name (string), initialState (object), and actions (object) properties.
name string
The name of the service and it defines how to access state for this service from the useLaunch hook.
initialState object
The beginning state for the service.
actions object
Service actions functions that can be called to change the state for the service. A service function receives context and payload arguments and it must return a new service state object.
The context argument is an object that consists of state, and actions properties. These are the same types that are returned from the useLaunch hook except that they are scoped to the local service. Service actions can be launch other launch actions. An example of this can be found in the async example.
The payload argument is an object that is passed into the launch action.
It is recommended that your service functions do not mutate state. Instead they should return a brand new state object.
Service actions are able to launch actions and an example of this can be found in the async example.
const calculatorService = {
name: "calculator",
initialState: {
value: 0,
},
actions: {
increase: ({ state, actions }, payload) => ({
value: state.value + payload,
}),
decrease: ({ state, actions }, payload) => ({
value: state.value - payload,
}),
},
};