Reducers Creator

reducersCreator is a helper function with which we create reducer functions for Redux.

Instalation

npm install redux-cool

Usage

import {reducersCreator} from "redux-cool"
const initial_state = {    profile: {        data: null,        loading: false,    }}
const account_reducer_tree = {    PROFILE: {        FETCH: {            START: (state, action) => {                state.profile.loading = true            },            SUCCESS: (state, action) => {                const [data] = action.args                state.profile.data = data                state.profile.loading = false            },            FAIL: (state, action) => {                state.profile.loading = false            }        },        UPDATE: {            EMAIL: (state, action) => {                const [email] = action.args                state.profile.data.email = email            },            USERNAME: (state, action) => {                const [username] = action.args                state.profile.data.username = username            }        }    },    CLEAR: (state, action) => {        return initial_state    }}
const accountReducer = reducersCreator(    "ACCOUNT",    initial_state,    account_reducer_tree,)
export default accountReducer

As you can see in the example above, we create an accountReducer by calling the reducersCreator function and passing it three arguments:

• "ACCOUNT" : It's a name of the reducer, it can be any string.
• initial_state : It's a initial state of the reducer, it can be any object.
• account_reducer_tree : It's a reducer tree object, in which the action handlers are defined - as an argument action handler functions take state and action and update the state. It automatically uses the immer library to do immutable updates with normal mutative code, like state.profile.data.email = email. There is no need to manually do immutable updates and return the result. If you are not familiar with the immer library, please look at it, it is very important.

As a result, we get the accountReducer function, which can handle the following type of actions:

Global Context	Local Context
"PROFILE/FETCH/START"	"ACCOUNT/PROFILE/FETCH/START"
"PROFILE/FETCH/SUCCESS"	"ACCOUNT/PROFILE/FETCH/SUCCESS"
"PROFILE/FETCH/FAIL"	"ACCOUNT/PROFILE/FETCH/FAIL"
"PROFILE/UPDATE/EMAIL"	"ACCOUNT/PROFILE/UPDATE/EMAIL"
"PROFILE/UPDATE/USERNAME"	"ACCOUNT/PROFILE/UPDATE/USERNAME"
"CLEAR"	"ACCOUNT/CLEAR"

As you can see, each handler can work with two types of actions (Global and Local), first consisting of the path described in reducerTree, the second is the same as the first type plus the reducer name that should be added in the beginning like "CLEAR" and "ACCOUNT/CLEAR". That is the most important and useful feature of this library. See Global and Local Actions for more details.