redux-modifiers

A collection of generic functions for writing redux reducers to operate on various data structures

Usage no npm install needed!

<script type="module">
  import reduxModifiers from 'https://cdn.skypack.dev/redux-modifiers';
</script>

README

Write better Redux code faster v0.0.5

Big changes from 0.0.4! API has been completely rewritten on top of ImmutableJS.

Codeship build status

A collection of generic functions on top of ImmutableJS and Redux Actions for simplifying your reducers. Declare your reducers and state as plain old javascript objects, but take advantage of Immutable guarantees and data structure traversal utilities.

Example reducer:

import { reducer, push, updateIn, removeIn } from 'redux-modifiers'

const reducer = reducer({
  'ADD_ITEM_TO_LIST': push,
  'UPDATE': updateIn,
  'ADD_NESTED_ITEM': (state, action)=>{
    let { selected, value } = action.payload; //Index of nested item (could be deeply nested, i.e. [0, 'key', 1])
    return state.updateIn(selected, item => item.push(value) ); //Using ImmutableJS API
  },
  'REMOVE': removeIn
}, []);

You can call toJS on any structure you get out of the reducer to convert it back to vanilla js, i.e. in a react component where you want to use spread operators, normal object accessors, etc. Anything you put in the reducer will automatically be converted to an ImmutableJS structure, which means you can do things like adding items to state from plain javascript objects without worrying about references sticking around.

Notes

FSA

redux-modifiers does expect that actions are dispatched as Flux Standard Actions. Essentially, this means every action looks like:

{
  type: YOUR_ACTION_TYPE,
  payload: YOUR_PAYLOAD
}

State and ImmutableJS

state is converted to an Immutable data structure, so you are free to use any ImmutableJS function you like on state. If you find you perform a particular option frequently, consider submitting a pull request and adding it to redux-modifiers!

Targeting specific parts of state

Use updateIn, to target specific parts of state, passing the update function the path that you want to update. Example state:

{
  foo: [
    {
      id: 1,
      name: 'Calvin'
    }
  ]
}

Example reducer function:

'UPDATE': updateIn

Example dispatch:

dispatch({selected: ['foo', 'name'], value: 'Calvin Froedge'});

API

push(state, action)

Payload can take any value, but you must call push on an array (List in ImmutableJS).

'ADD': push

updateIn(state, action)

Payload must include a selection path selected and a value or fn. State (or targeted key) will be replaced with value if value, or fn will be applied to the existing value.

Example payload:

{selected: [0, 'nested_array', 1], fn: value => value * 2}

removeIn(state, action)

Payload must include a selection path. Example payload:

[0, 'nested_array', 1]