$ npx create-react-app [my-app] --use-npm

$ cd [my-app]

$ npm install react-router-dom

$ npm start

https://primereact.org/installation/

$ npm install primereact primeicons

imports needed for prime

import "primereact/resources/themes/lara-light-indigo/theme.css";  //theme //can change

import "primereact/resources/primereact.min.css";   //core css

import "primeicons/primeicons.css";                                //icons

https://www.npmjs.com/package/axios

$ npm install axios  // npm install axios 

$ npm install @feathersjs/client @^4.5.11  // npm install feathers client

Configure the Feathers Client: In your React app, create a new file called feathers.js and add the following code:

import feathers from '@feathersjs/client';

import axios from 'axios';

const app = feathers();

const restClient = feathers.rest('http://localhost:3030');

app.configure(restClient.axios(axios));

export default app;

This code sets up a new instance of the Feathers client and configures it to use the feathers.rest and axios libraries to make API calls to the Feathers server running on http://localhost:3030. 

import React, { useEffect, useState } from 'react';

import feathers from './feathers';

function App() {

  const [users, setUsers] = useState([]);

  useEffect(() => {

    feathers.service('users').find()

      .then(result => setUsers(result.data))

      .catch(error => console.error('Error fetching users', error));

  }, []);

  return (

    <div>

      <h1>Users</h1>

      <ul>

        {users.map(user => (

          <li key={user._id}>{user.firstName} {user.lastName}</li>

        ))}

      </ul>

    </div>

  );

}

export default App;

This code uses the feathers.service method to fetch a list of users from the users service on the Feathers server and updates the users state variable with the response data. The useEffect hook is used to ensure that the API call is only made once when the component is mounted.

In summary, integrating React and Feathers is a powerful way to build full-stack web applications. By configuring the Feathers client in your React app and using it to make API calls from your components, you can build dynamic and interactive user interfaces that interact with a powerful back-end API.

Rematch is a Redux framework for building applications that allows developers to manage the state of their application in an organized and predictable way. Here's an overview of how to use Rematch for state management in a React app: 

1. Install Redux : To use Redux, you first need to install it in your React app. In your terminal, navigate to the root directory of your React app and run the following command:

npm install redux react-redux

This will install the Redux and React-Redux libraries.

2. Install Rematch: To use Rematch, you first need to install it in your React app. In your terminal, navigate to the root directory of your React app and run the following command: 

npm install @rematch/core @rematch/loading  //mainly we are using this

This will install the Rematch and React-Redux libraries. 

3. Create a Store: The first step in using Redux is to create a store. A store is an object that holds the entire state of your application. In your React app, create a new file called store.js and add the following code:

import { createStore, applyMiddleware } from 'redux';

import { createLogger } from 'redux-logger';

import thunk from 'redux-thunk';

import feathersClient from './feathers';

import rootReducer from './reducers';

const loggerMiddleware = createLogger();

const store = createStore(

  rootReducer,

  applyMiddleware(thunk, loggerMiddleware)

);

feathersClient.then(app => {

  store.dispatch({ type: 'INIT_FEATHERS', payload: app });

});

export default store;

This code creates a new store using the createStore method from the Redux library and the rootReducer function that will be defined in the next step. It also uses the applyMiddleware method to apply middleware to the store. The createLogger function is used to log state changes in the console, while the thunk middleware is used to enable asynchronous actions.

The feathersClient variable is a Promise that connects to the Feathers server and returns the Feathers app object. The store.dispatch method is used to dispatch an action to the store when the app is initialized.

3. Define Reducers: In your React app, create a new directory called reducers and add a new file called index.js. Add the following code:

const initialState = {

  feathers: null

};

function rootReducer(state = initialState, action) {

  switch (action.type) {

    case 'INIT_FEATHERS':

      return {

        ...state,

        feathers: action.payload

      };

    default:

      return state;

  }

}

export default rootReducer;

This code defines a rootReducer function that takes the current state of the application and an action and returns the new state of the application. The initialState object is the initial state of the application, which includes a feathers property with a value of null. The INIT_FEATHERS action initializes the feathers property with the Feathers app object.

4. Create Actions: In your React app, create a new file called actions.js and add the following code:

import feathers from './feathers';

export function findUsers() {

  return dispatch => {

    feathers.service('users').find()

      .then(result => dispatch({ type: 'FIND_USERS', payload: result.data }))

      .catch(error => console.error('Error fetching users', error));

  };

}

This code defines a findUsers action that returns a function that takes a dispatch argument. The dispatch method is used to dispatch an action to the store when the users are found. The feathers.service method is used to fetch a list of users from the users service on the Feathers server.

5. Connect Components to the Store: Now that you have defined the store, reducers, and actions, you can connect your components to the store using the `connect` function from the `react-redux` library and Rematch's model-based approach.

**Using Rematch Models (Recommended):**

Rematch simplifies Redux by introducing the concept of "models." A model is a self-contained unit that defines its state, reducers, and effects (which handle asynchronous operations like API calls).

1.  **Install Rematch Loading Plugin (if you haven't already):**

    ```bash

    npm install @rematch/loading

    ```

2.  **Create Rematch Models:** Create a new directory called `models` in your `src` folder (or a similar location). Inside this directory, create a file for each part of your application's state you want to manage. For example, `users.js`:

    ```javascript

    // src/models/users.js

    import feathers from '../feathers';

    export const users = {

      state: {

        list: [],

        isLoading: false,

        error: null,

      },

      reducers: {

        setLoading: (state, payload) => ({ ...state, isLoading: payload }),

        setUsers: (state, payload) => ({ ...state, list: payload }),

        setError: (state, payload) => ({ ...state, error: payload }),

      },

      effects: (dispatch) => ({

        async fetchUsers() {

          dispatch.users.setLoading(true);

          try {

            const result = await feathers.service('users').find();

            dispatch.users.setUsers(result.data);

            dispatch.users.setLoading(false);

          } catch (error) {

            console.error('Error fetching users', error);

            dispatch.users.setError(error.message || 'Failed to fetch users');

            dispatch.users.setLoading(false);

          }

        },

      }),

    };

    ```

3.  **Configure Rematch Store:** Update your `store.js` file to use Rematch:

    ```javascript

    // src/store.js

    import { init } from '@rematch/core';

    import * as models from './models'; // Import all your models

    import loadingPlugin from '@rematch/loading';

    import feathersClient from './feathers';

    const loading = loadingPlugin();

    const store = init({

      models,

      plugins: [loading],

    });

    feathersClient.then(app => {

      store.dispatch({ type: 'INIT_FEATHERS', payload: app });

    });

    export default store;

    ```

4.  **Provide the Store to Your App:** In your main application entry point (e.g., `index.js`), wrap your root component with the `Provider` component from `react-redux`:

    ```javascript

    // src/index.js

    import React from 'react';

    import ReactDOM from 'react-dom/client';

    import App from './App';

    import { Provider } from 'react-redux';

    import store from './store';

    const root = ReactDOM.createRoot(document.getElementById('root'));

    root.render(

      <Provider store={store}>

        <App />

      </Provider>

    );

    ```

5.  **Connect Components:** In your React components, use the `connect` higher-order component to access state and dispatch actions from your Rematch models:

    ```javascript

    // src/components/UserList.js

    import React, { useEffect } from 'react';

    import { connect } from 'react-redux';

    const UserList = ({ users, fetchUsers, isLoading, error }) => {

      useEffect(() => {

        fetchUsers();

      }, [fetchUsers]);

      if (isLoading) {

        return <div>Loading users...</div>;

      }

      if (error) {

        return <div>Error: {error}</div>;

      }

      return (

        <div>

          <h2>User List</h2>

          <ul>

            {users.map(user => (

              <li key={user.id}>{user.email}</li>

            ))}

          </ul>

        </div>

      );

    };

    const mapStateToProps = (state) => ({

      users: state.users.list,

      isLoading: state.loading.effects.users.fetchUsers, // Access loading state for the effect

      error: state.users.error,

    });

    const mapDispatchToProps = (dispatch) => ({

      fetchUsers: dispatch.users.fetchUsers,

    });

    export default connect(mapStateToProps, mapDispatchToProps)(UserList);

    ```

**Explanation of Rematch Approach:**

* **Models:** Encapsulate state (`state`), synchronous state updates (`reducers`), and asynchronous operations (`effects`).

* **`init`:** The Rematch function to create your store, taking your models and plugins.

* **`dispatch`:** Accessed through the `connect` function, allows you to trigger actions defined in your model's `effects`. Rematch automatically creates action creators for your reducers and effects.

* **`loadingPlugin`:** Provides a convenient way to track the loading state of your effects. You can access the loading status for a specific effect using `state.loading.effects.[modelName].[effectName]`.

**Alternative (Without Rematch Models, using plain Redux actions):**

If you prefer to stick closer to the original Redux structure without fully adopting Rematch models, you would continue as follows:

1.  **Import `connect`:**

    ```javascript

    import { connect } from 'react-redux';

    ```

2.  **Define `mapStateToProps`:** This function takes the entire Redux store state and returns an object containing the specific parts of the state that your component needs.

    ```javascript

    const mapStateToProps = (state) => {

      return {

        feathersApp: state.feathers,

        // Add other state mappings as needed

      };

    };

    ```

3.  **Define `mapDispatchToProps`:** This function takes the `dispatch` function from the Redux store and returns an object containing functions that, when called, dispatch actions to the store.

    ```javascript

    const mapDispatchToProps = (dispatch) => {

      return {

        findUsers: () => dispatch(findUsers()), // Assuming you have the findUsers action

        // Add other action dispatchers as needed

      };

    };

    ```

4.  **Connect Your Component:** Use the `connect` higher-order component to wrap your React component:

    ```javascript

    import React from 'react';

    import { connect } from 'react-redux';

    import { findUsers } from './actions'; // Import your actions

    const MyComponent = (props) => {

      // Access state via props.feathersApp, props.someOtherState

      // Dispatch actions via props.findUsers()

      return (

        <div>

          {props.feathersApp ? <p>Feathers App Initialized!</p> : <p>Initializing Feathers...</p>}

          <button onClick={props.findUsers}>Fetch Users</button>

          {/* Render user list or other data */}

        </div>

      );

    };

    export default connect(mapStateToProps, mapDispatchToProps)(MyComponent);

    ```

**Choosing the Approach:**

* **Rematch Models:** Highly recommended for cleaner, more organized, and less boilerplate code. It simplifies Redux development significantly, especially for larger applications.

* **Plain Redux with `connect`:** Provides more explicit control but can lead to more verbose code, especially when dealing with asynchronous actions and loading states.

For integrating FeathersJS with Redux, the Rematch model approach often leads to a more streamlined and maintainable codebase due to its built-in handling of asynchronous operations and state updates within the model. Remember to adapt the model structure and actions to the specific data and services you are using in your FeathersJS application.

For more information on redux go to: https://redux.js.org/introduction/getting-started

For more information on RematchJS go to: https://rematchjs.org/docs/