redux-flash

redux-flash

Redux action creators for displaying flash messages.

This library provides a simple way to manage flash messages in Redux applications. It includes action creators for creating configurable flash messages as well as selectors for accessing those messages from anywhere in your application.

Migration guides

• v2.0.0

Example

import { applyMiddleware, createStore, combineReducers } from 'redux'
import {
    reducer as flashReducer,
    middleware as flashMiddleware,
    flashMessage,
    getFlashMessages,
} from 'redux-flash'

// First, include the flash reducer keyed under 'flash' in your root reducer

const reducer = combineReducers({
    flash: flashReducer
    ...
})

// Then, apply the flash middleware when creating the store

const store = createStore(reducer, {}, applyMiddleware(flashMiddleware()))

// Now you can dispatch flash actions

const action = flashMessage('This is a test message!')
store.dispatch(action)

// And access messages from the state

const state = store.getState()

getFlashMessages(state)
// =>
// [{
//    id: 1495649041702,
//    message: 'This is a test message!',
//    isError: false,
//    props: {}
// }]

API

Action creators

redux-flash exposes the following action creators:

• flashMessage(message, options): Create a flash message with a given message string.
• flashErrorMessage(message, options): Create a flash message with the isError option flag set to true.
• flashSuccessMessage(message, options): An alias for flashMessage().
• clearMessages(): Clear all flash messages.
• removeMessage(messageID): Clear a particular flash message.

The options object passed to these action creators may contain the following attributes:

• push: A flag indicating that only the new message should be shown. Internally calls clearMessages() before adding the new message.
• isError: A flag indicating whether the message is an error message.
• timeout: A timeout (ms) after which the message will be removed (default: 3000). If this value is false, the message will persist indefinitely.
• props: Any additional values to pass to the message object.

Middleware

You can also modify the behavior of flash messages globally by passing options to the flash middleware:

const flashOptions = { timeout: 5000 }
const store = createStore(reducer, {}, applyMiddleware(flashMiddleware(flashOptions))))

The options object passed to the middleware may contain the following attributes:

• timeout: A timeout (ms) after which the message will be removed (default: 3000).
• props: Default props that will be merged with each message's props.

Selectors

redux-flash exposes the following state selectors:

• getFlashMessages: Retrieves all flash messages from the state.
• getSuccessMessages: Retrieves all flash messages from the state where isError: false.
• getErrorMessages: Retrieves all flash messages from the state where isError: true.
• getLatestMessage: Retrieves the last flash message that was added to the state.

Message objects returned by these selectors will have the following format:

{
   id: 1495649041702, // A unique ID
   message: 'This is a test message!', // The message text
   isError: false, // Whether the message is an error
   props: {} // Any additional values you passed in your action creator
}

A PropType for this object is exported from this module as flashMessageType.

Reducer

redux-flash exposes a reducer to handle the actions it creates. This reducer must be attached to your root reducer using the key flash in order for the library to function (see example).

Displaying messages in the view

redux-flash only handles the creation and storage of flash messages, and contains no display logic. Here's a simple example of how such logic could be implemented using react-redux:

import React from 'react'
import PropTypes from 'prop-types'
import { connect } from 'react-redux'
import { getLatestMessage, flashMessageType } from 'redux-flash'

function FlashMessages ({ flash }) {
    return (
        <div>
        {
            flash && <div>{ flash.message }</div>
        }
        </div>
    )
}

FlashMessages.propTypes = {
    flash: flashMessageType
}

function mapStateToProps (state) {
    return {
        flash: getLatestMessage(state)
    }
}

export default connect(mapStateToProps)(FlashMessage)