Understanding Redux Toolkit Query and its Applications in Web App Development

Redux Toolkit Query & Its Applications In Web App Development

Web applications are required to extract data from the servers before it is displayed to the end user. While doing it doesn’t take much time, it does add to the work and take a hit on the user experience.  

In addition to extracting data, these applications also have to update data frequently and send updates to the servers. Redux Toolkit Query, or RTK Query, is a valuable tool for web application development companies. They can use it to fetch and cache data.  

With RTK Query, developers won’t have to write data fetching and caching logic, which saves a lot of time and speeds up the process. In this article, we will explore more about RTK Query, its benefits, and its implementation.  

Understanding Redux Toolkit Query RTK Query

Taking our discussion forward from the previous section, web applications work in a complex manner regarding data management. Fetching, caching, and updating data is pivotal to a smooth operation but is time-consuming. Developers are supposed to write different logic scripts for all these actions plus for synchronizing the cached data available with the client and with the server. All these components make working with a web application complex.  

More challenges arise when the developers have to implement other behaviors as well, including; 

  • Get information about the loading State for showing it to the UI Spinners.  
  • Prevent users from making duplicate requests for the same data.  
  • Making updates for a faster UI 
  • Managing cache lifetimes when the users interact with the application UI.  

Redux has always had a minimal structure at the base. The onus of building the logic and writing the code is on the developers. In the past, the developers did not get any help from Redux to solve common development problems. They did have some documentation on the common dispatching actions patterns related to the request lifecycle and tracking loading state. Plus, Redux shared documentation on createAsyncThunk API.  

Why Bring Redux Toolkit Query When Developers Already Have React Query?

Critics might say that React Query and RTK Query are similar, so why have two solutions for the same thing? Well, the difference lies in how RTK Query can directly integrate with Redux. Using the Async Thunk API limits flexibility, which RTK Query addresses.  

Over the years, the react development community has understood that data fetching and caching have different requirements and concerts than state management. RTK Query takes inspiration from tools that help with data fetching and adds a more enhanced approach to the API design.  

Here are some of the benefits associated with using RTK Query; 

  • For data caching and caching logic, developers can use Redux’s Toolkit APIs createSlice and createAsyncThunk. 
  • You can use the RTK Query functions with any UI layer as it is UI-agnostic.  
  • In RTK Query, developers can define the API endpoints ahead of time.  
  • Using the data and isLoading fields, RTK Query can create React hooks covering the complete data fetching process. Plus, using the same tool, developers can also manage cached data lifetime in the form of components mount and unmount.  
  • After fetching the initial data, developers can use RTK Query to cache the entry lifecycle for streaming cache updates through the WebSocket messages.  
  • Written in TypeScript, the RTK Query provides a smooth user experience.  

Using RTK Query, developers can define the APIs and endpoints for data fetching, create cached and memorized selectors for data access, and handle error states. In addition to data extraction and management, it can help with pagination, sorting, filtering, and general data manipulation functions.  

RTK Query Implementation

RTK Query implementation begins with installing RTK Query on the terminal, and for the same, use the command given below; 

npm install @reduxjs/toolkit react-redux 

Redux store for a web application works as a centralized data repository holding the entire state of the application. This store holds data shared across multiple components for tasks like user authentication information or data fetched through an API.  

Redux store for a web application-min

Basically, using a Redux store means simplifying the process of data transfer between the web application components. Moreover, it helps with application management making it more organized and stable.  

Hence, the src/app/store.js address where the Redux store is built (store.js) is the store name, and src/app is the repository.  

Followed by this, configure the  Redux Store marking the source of the implementation src/app/store.js, with the following command; 

Followed by this, configure the  Redux Store marking-min

This code snippet makes the Redux store work in a web application environment. We can create the store with the command (import { configureStore } from ‘@reduxjs/toolkit’).  

The rest of the code script is for configuring the RTK Query and allowing it to handle the network requests and network responses. Other functions you will complete in this code snippet include; 

  • Make API requests to the JSON server 
  • Call the reducer property to define how the store state must be updated.  
  • Apply the middleware function and apply it to the store. These reducers are third-party extensions point working between two variables, dispatching an action and the moment when the action reaches the reducer. Using this function, we can log reducer activities, crash reporting, and communicate with asynchronous API.  
  • The setupListeners function is added to handle network requests and cache responses.  

Setting Up Boolean dev tools

Boolean devTools is an important part of the development exercise, and it integrates with the Redux applications. The purpose is to see how the current state changes when actions are dispatched. Moreover, we can also use it for tracking performance, action history, and debugging the application.  

With the RTK Query, Boolean devTools goes one step further and shows how queries and mutations are happening to the API. Developers can see the status of each request made and identify the request methods and URL. To use Boolean devTools, install the Google Chrome extension and make sure to configure it according to the requirements.  

preloadedState in RTK Query

In RTK Query, preloadedState is an argument passed to the configureStore required to create a new store. The purpose is to specify the state of the store required to hydrate the application state from initial storage or from the server.  

Developers can use it to pre-populate the store with data already available in the storage before the application starts. One of the benefits of preloadedState in RTK Query is that it allows reducers to define the default values for the output data.  

So the dual purpose of preloadedState is to specify the default arguments and load existing data. The benefit is simplification of web application’s data management and ensure better performance.  

Next Step | Integrate the Redux Store in App.js Parent

Moving on, include the Redux store to App.js parent, which helps Redux applications provide access to the store and all its components within the application. The ‘Provider’ component within the ‘react-redux’ library binds the React components and Redux store. For this purpose, use the code snippet, given below; 

Next Step Integrate the Redux Store in App.js Parent-min

As a result, any component in the application can gain access to the store and the data within the ‘useSelector’ hook. Using this function, developers can not only extract data but also see to the changes in the store’s state.  

Creating Redux State Slice

Slice in Redux store is a function containing state and actions for a particular part of the application. Using the createSlice function, we can generate a function to take a specific action. Combined with the addTodo function, developers can further dispatch the action from any given component within the web application.

Creating Redux State Slice-min

In the code snippet above, the slice is named todoslice, which depicts the initial state of an empty array. The array is about the list of todos for the application. Naming a single action with addTodo component, the functions take the payload (according to the text given to the Todo function) and add another todo object. Each of these will have a unique array ID for the main state array.  

Moving on, the export default todoslice.reduce is added to export the reduce function and make it the default export. Due to this, the reduce in the configureState function can be utilized to create the redux store. As a result, using this code snippet, developers can generate actions and reducers from Redux slices. The result is that developers can create a more manageable and scalable Redux store. Moreover, using this, developers won’t have to implement the Redux reducer manually.  

However, when the task is to update the React State, it cannot be done without creating new data for this action. However, with the Immer function, it can be done easily, and the state can be changed directly. See the code snippet below to realize this function.  

Using Immer, developers can change the state directly, and here’s an example of how to do the same;  

Using Immer, developers can change-min

Mind that we are not returning anything from this code snippet. Rather we are only showing an example of the addToDo render function. For updating the state of the Redux function, employ the concept of immutability; here, we can use the return function as well.  

Mind that we are not returning anything-min

Moving On, Add Slice Reduces to the Store

For further management, a web application development company can add Slice Reduce to the store with a single todos slice of state. To manage this slice, developers can use the todoReducer function. The purpose here is to manage the state in the React application, which can be accessed from different components, including useSelector and useDispatch hooks.  

Moving On, Add Slice Reduces to the Store-min

The code snippet demonstrates how to use the configureStore function present within the @reduxjs/toolkit. Here, the configureStore function we have used takes an object in the form of an argument and then specifies the configuration for the same in the Redux store. For our example, the object is the reducer property.  

Using the todoReducer from the features/todo/todoslice created with the createSlive from the same toolkit. The motive is to specify how the todo slice of the Redux store updates according to the different actions.  

Implementing useSelector and useDispatch in React Native Components

useSelector and useDispatch are hooks used in React Native. They are alternatives to the connect () higher-order component, which is currently used. You can equalize map state props to useSelector, and map dispatch props are similar to useDispatch.  

Starting with useSelector

The useSelector React-Redux hook is utilized to extract values from the global state. Using this hook component, developers can extract any state they require to be used in the component functioning.  

This code snippet shows how to utilize the useSelector hook to access the required state from the Redux store while working with React components. For this example, the component used is ‘Todos.’ 

The hook function understands the function as an argument, as we have discussed before and specifies the parts of the store state that needs to be selected. As the function retrieves the store state argument information, it returns the selected state.  

Using this function, developers can iterate over different ‘todos’ and render a list of items for each todo function. As we have used the ‘key’ attribute in the code snippet, it provides a unique identifier to each list item. 


The useDispatch hook in the React-Redux library of components is used to dispatch actions to the Redux store. Developers use this component to complete actions from the component. Using useDispatch is also important when developers want to change the global state 

The useDispatch code snippet above uses the addTodo component, which we first have to create and then import the useDispatch hook from the React-Redux library. Using this code snippet, the developers create a dispatch function utilizing the same for dispatching the requisite action and adding it to the new todo item list.  

We can also use the useHandler function in the same snippet at a time of submitting the form. This function also dispatches an action to the new todo item list of the state but from the addTodo action creator file.


This blog covers the basic functions of RTK query. From setting up the RTK query to using the components and hooks from the React-Redux store, this blog aims to help you get started with the RTK Query. As this function simplifies how developers work with asynchronous data fetching in Redux, developers get a consistent and intuitive development experience.  

For more assistance on RTK Query and how it can be used in creating web applications, get in touch with DevIT, a web application development company. We offer premium development services delivered through expert developers.