Smaple

DeviceStore.ts

import { observable } from 'mobx'
import { persist } from 'mobx-persist'

class DeviceStore {
    @persist @observable public deviceId: string = ''

    constructor() {
        this.resolevDeviceId = this.resolevDeviceId.bind(this)

        this.resolevDeviceId()
    }

    async resolevDeviceId() {
        let foundUUID = await this.getFromCache()
        if (foundUUID === null) {
            // generate new uuid
            foundUUID = 'NEWUUID'
            await this.saveToCahch(foundUUID)
        }
        this.deviceId = foundUUID
    }
    async getFromCache(): Promise<string | null> {
        return Promise.resolve('UUID')
    }
    async saveToCahch(uuid: string) {
        Promise.resolve(uuid)
    }
}