React FSM Router

Building a react router using statecharts concepts

This project is in its very early stages! Feature requests are definitely welcome.

Quick Start

Clone the repo to look at the quickstart example. Alternatively:

Usage

install

npm install react-fsm-router

import the component:

import Router from 'react-fsm-router';

Wrap your application code inside the Router. You must give the router an fsm (finite state machine) and set of transitions (see below)

<Router
    fsm={fsm}
    transitions={transitions}
    fallback={<div>loading</div>}
    >
    <Frame/>
</Router>

These components (only at the top level) will be passed a prop router (see full API definition below). Trigger a transition by calling router.TRANSITION.

<Button onClick={() => this.props.router.TRANSITION('TOGGLE')}

You can access the current route (i.e. to render different pages) via router.getRoute()

let route = router.getRoute();
return route[0] === 'view' ? <View/> : <Edit/>

FSM

as per xstate - you can use the xstate viz tool to help build these. It currently only supports the simple syntax as shown below.

const fsm = {
    initial: 'section1',
    states: {
        section1: {
            on: {
                TOGGLE: 'section2'
            },
            initial: 'part1',
            states: {
                part1: {
                    on: {
                        CHANGE_PART: 'part2'
                    }
                },
                part2: {
                    on: {
                        CHANGE_PART: 'part1'
                    }
                }
            }
        },
        section2: {
            on: {
                TOGGLE: 'section1'
            }
        }
    }
};

Transitions

Each transition must have a unique key. The transitions receive two arguments:

• {router, args}
  • router is the current state of the router
  • args are what was passed as the second argument to router.TRANSITION. This will always be undefined if a transition is called when initialising your app for the first time (i.e. someone has navigated directly to that state via a URL)
• callback - a callback that must be called to end the transition

const transitions = {
    TOGGLE: function({ args, router }, cb) {
        console.log('toggling');
        router.clearQueryMap();
        cb();
    },
    CHANGE_PART: function({ args, router }, cb) {
        console.log('changing part');
        cb();
    }
};

Router API

The component Router will pass an object router to its direct children, with the following methods:

• TRANSITION triggers a transition arguments (args, callback)
• getRoute returns an array of strings representing the route (e.g. ['section1','part1'])
• getHistory returns an array of arrays, where each array represents a route the user has gone to
• clearHistory clears the history
• getQueryMap returns the query map (e.g. {id:'123'})
• clearQueryMap clears the query map
• setQueryMap sets the query map (as a delta) - if you want to explicitly clear it you can give it {key:undefined}

All the setters and clearers take a final argument as a callback if you need to confirm the state change has occurred before continuing.

Behaviour

If you use the baseURL of your application, the router will redirect to the URL of your initial state. If you use a specific URL which maps to a particular state, the router will call the transitions required to get from the initial state to that state, in order, asynchronously. Note that args will be undefined. It will also auto-complete the initial state (e.g. /section1 in the example will redirect to /section1/part1). The querystring at the end of the URL will be maintained unless you explicitly clear it using clearQueryMap.