Login Controller with State Machine

LoginController.js

// @flow
import React from 'react'
import axios from 'axios'
import R from 'ramda'

import Login from './Login'

/**
 * LoginController
 */

const loginMachine = {
	start: {
		SUBMIT: 'thinking',
	},
	thinking: {
		LOGIN_SUCCESS: 'success',
		LOGIN_FAILURE: 'error',
	},
	error: {
		SUBMIT: 'thinking',
	},
	success: {
		CANCEL: 'start',
	},
}

type Props = {}
type State = {
	loginState: string,
	loginError: string,
}

type LoginFormData = {
	email: string,
	password: string,
}

type Action = {
	type: string,
	errorMessage?: string,
	formData?: LoginFormData,
}

class LoginController extends React.Component<Props, State> {
	constructor(props: {}) {
		super(props)
		this.state = {
			loginError: '',
			loginState: 'start',
		}
	}

	command(nextState: string, action: Action) {
		switch (nextState) {
			case 'thinking':
				return this.attemptLogin(action.formData)
			case 'error':
				return {
					loginError: action.errorMessage,
				}
			default:
				break
		}
	}

	attemptLogin(credentials: LoginFormData): void {
		axios
			.post('//localhost:3000/auth/login', credentials)
			.then((response) => {
				console.log(response)
				this.transition({ type: 'LOGIN_SUCCESS' })
			})
			.catch((err) => {
				console.log(Object.keys(err))
				console.log(err.response)
				const errorMessage = R.path(['response', 'data', 'message'], err).toString() || 'Invalid credentials'
				this.transition({ type: 'LOGIN_FAILURE', errorMessage })
			})
	}

	handleLogin = (formData: LoginFormData) => {
		this.transition({ type: 'SUBMIT', formData })
	}

	transition(action: Action) {
		const currentState = this.state.loginState
		const nextLoginState = loginMachine[currentState][action.type]

		if (nextLoginState) {
			const nextState = this.command(nextLoginState, action)
			this.setState({
				loginState: nextLoginState,
				...nextState,
			})
		}
	}

	render() {
		return <Login loginError={this.state.loginError} loginState={this.state.loginState} handleLogin={this.handleLogin} />
	}
}

export default LoginController