reduxr-reducer-helpers

A utility to handle common array manipulation reducer functions.

Part of the reduxr family of packages.

Usage

A vast majority of reducers deal with arrays, and need to be able to remove an item by it's id, or to modify an item by its id.

It's pretty common to see a Redux reducer that looks something like this:

export default objReducer([], {
  // Use id to remove a certain member of a list
  removeMember_done: (state, {data}) => state.filter(m => m.id !== data.id),

  // Use id to update a certain member of a list
  activateMember_done: (state, {data}) =>
    state.map(m => m.id === data.id ? {...m, isActive: true} : m)
})

This can be done more simply by using reduxr-reducer-helpers.

import {setPropsByDataId, removeByDataId} from 'reduxr-reducer-helpers';

export default objReducer([], {
  // Remove a specified member from the list...
  removeMember_done: removeByDataId,

  // Find a specified member and update it...
  activateMember_done: setPropsByDataId({ isActive: true })
})

Helper functions

There are a handful of functions in reducer-helpers. You can check out the source. But here's the list:

removeById - Remove an item from an array using the action.id property.

removeByDataId - Remove an item from an array using the action.data.id property (useful when dealing with ajax results)

setPropsById - Sets properties of any items in an array that whose id matches action.id

setPropsByDataId - Sets properties of any items in an array that whose id matches action.data.id (useful when dealing with ajax results)

These four functions cover many common scenarios.

Modifying an item in a list

The setPropsById and setPropsByDataId functions are used to modify an item in a list. They can be passed an object which contains literal property values:

setPropsById({name: 'John'})

Or they can be passed a function which takes an action and returns the properties to be set:

setPropsById(action => ({name: action.fullName}))

The item being modified is also passed as an optional second parameter:

toggleIsComplete((_, item) => ({isComplete: !item.isComplete}))

License MIT

Copyright (c) 2015 Chris Davies

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.