Redux Thunk vs Redux Saga: Which One is the Best?

OnManaging asynchronous logic in large React applications can become complex. This is where middleware like Redux Thunk and Redux Saga step in. Redux Thunk and Redux Saga are popular choices for handling asynchronous actions in Redux. Redux-thunk vs. redux-saga, which one is better? 

The main difference between Redux Thunk and Redux Saga is that Redux Thunk uses plain functions to delay dispatching actions until async logic has been completed. This keeps actions clean while allowing async logic in action creators. Redux Saga takes a different approach, using generators to write asynchronous flows in a synchronous-looking way. 

Though their methods differ significantly, they help handle Redux async logic. The main ideas and applications of Redux Thunk vs. Redux Saga will be discussed in this article.

Redux Thunk vs Redux

In Redux applications, Redux-Saga and Redux Thunk assist in managing asynchronous code. Managing changes in the app’s state is made simple with the help of the Redux state management library. The store is an object that contains all of the app’s state data.

The middleware between actions and the store is Redux Thunk and Redux Saga. They let us handle asynchronous tasks like API calls from within Redux. Both help deal with “side effects” like asynchronous logic that would otherwise make our code messy.

Redux Thunk is more straightforward – it lets action creators return functions instead of actions. This function receives the store’s dispatch method. Redux Saga uses ES6 generators to handle async logic through “sagas.” Overall, both help manage complex asynchronous logic in Redux. This must have let you know about Thunk vs Saga Redux.

See Also: Redux Vs React Query: An In-Depth Comparison

Why Redux? Redux to Your Rescue

Managing state changes across large apps can become complex. With a central state management system, keeping track of data changes is hard. This leads to bugs as the state gets out of sync between different components.

Redux solves this with its single source of truth approach. The whole state of the app is stored in an object tree within a single store. Any component can easily access this state. Redux also uses actions and reducers to predict state changes.

This makes debugging more accessible since we have a record of exactly how the state was updated. It also prevents bugs from conflicting writes to state. With Redux, state management is more straightforward, and our apps are easier to understand and maintain.

As you go into the world of state management, an interesting avenue to explore is the integration of React Query with Redux. This dynamic mix improves React applications’ ability to manage asynchronous data fetching. If you find the intricacies of Redux intriguing, the integration with React Query can provide a fresh perspective and a powerful solution to managing data in your applications.

Data Flow in Redux

In Redux, data flows in a single direction from top to bottom. First, components dispatch actions when something happens, like a user click. These actions are plain JavaScript objects that describe what happened.

The actions are sent to any middleware like Redux Thunk or Redux Saga. Middleware can handle asynchronous logic and then dispatch additional actions.

Next, actions reach the reducers. Reducers take the previous state and an action, then return to a new state. Finally, the store updates with the latest state from reducers. The UI re-renders to reflect any state changes.

This unidirectional flow makes Redux very predictable. Debugging is more straightforward since we can easily track how and why the state was updated.

What is a Redux middleware?

Middleware sits between actions and reducers in Redux. Standard middleware helps with asynchronous logic that would otherwise make code complex.

Redux Thunk and Redux Saga are popular middleware. Redux Thunk lets action creators return functions instead of actions. The Redux Saga uses ES6 generators to handle async logic through “sagas.”

Middleware intercepts actions before reaching reducers. This allows things like dispatching new actions from asynchronous operations. For example, middleware can handle API requests, so reducers don’t have to.

Using middleware keeps asynchronous logic separate from reducers. It avoids complex or nested callback code that’s hard to follow. Middleware makes Redux easier to use for real apps with complex asynchronous behavior.

See Also: UseContext Is Not Updating State: How To Fix?

What is Redux Thunk?

With the help of Redux Thunk, you can create action creators that return functions rather than action objects. This function can dispatch actions and handle asynchronous logic.

Redux Thunk operates by examining the action that is being incoming. If it is a standard action object, the reducer handles the action, and it does nothing. Nevertheless, if the action is a function, it calls it using the inputs given by the store’s getState and dispatch methods. The Thunk sends out the action to update the state when executing the asynchronous function.

Here is a simple example of a Thunk:

export const obtain articles = () => dispatch => {

  dispatch({ type: ACQUIRE_ARTICLES_REQUEST })

  return fetch(‘/api/posts)

    .then(response => response.json())

    .then(data => dispatch({ type: ACQUIRE_ARTICLES_SUCCESS, payload: data }))

    .catch(err => dispatch({ type: ACQUIRE_ARTICLES_FAILURE, err }))

}

How does Redux Thunk work?

With Redux Thunk, there are two parts – a thunk creator, an action creator that returns a thunk/async action creator, and the Thunk itself, which is the function returned by the thunk creator.

The thunk creator receives dispatch and getState as arguments. It can then dispatch regular actions and request API using libraries like Axios. Once the request is completed, it dispatches another action to update the state.

What is Redux Saga?

Redux Saga is a library that aims to make side effects like asynchronous logic easier to handle and more efficient to execute. It uses an ES6 feature called generators.

Here is a simple example of a Saga:

import { call as invoke, put as dispatch, take every as onEvery } from ‘redux-saga/effects’

function* retrieveArticles(action) {

   try {

      const articlesData = yield invoke(Api.retrieveArticles);

      yield dispatch({type: “FETCH_ARTICLES_SUCCESS”, articles: articlesData});

   } catch (error) {

      yield dispatch({type: “FETCH_ARTICLES_FAILURE”, errorMessage: error.message});

   }

}

function* customSaga() {

  yield onEvery(“FETCH_ARTICLES_REQUEST”, retrieveArticles);

}

export default customSaga;

How does Redux Saga work?

Redux Saga uses generator functions that can be paused and resumed. Effects like call, put, and takeEvery are used to call asynchronous functions, dispatch actions, and watch for specific actions.

The generator yields objects to the middleware rather than returning promises. This makes the asynchronous logic look synchronous using yield keywords. It also allows for features like the cancellation of tasks.

Who Wins?

Both libraries are helpful for asynchronous logic in Redux apps. Redux Thunk vs Saga difference: Redux Thunk is simpler for primary usage, while Redux Saga provides more powerful features and easy testing. Choosing depends on the complexity of async flows in the project. In most cases, either library can work based on developer preference. So that is all in Redux Thunk vs Saga. With this, you can know which one is the best.  

See Also: Mastering Redux-Saga Typescript: Full Guide

FAQs

Why is Redux Saga better than Redux Thunk?

Redux Saga provides more powerful features to handle complex asynchronous logic. Some key advantages are: 1. Easy testing - Saga effects can be tested without mocking 2. Cancellation support - Sagas allow canceling already started tasks 3. Better performance - Saga can optimize async code execution 4. Concurrency handling - Features like races, parallelism, etc.

Why should we use Redux Thunk?

Redux Thunk is more straightforward to use for basic asynchronous flows: 1. Easy to understand - Thunk code is a straightforward callback function 2. Minimal learning curve - No need to learn generators 3. Suitable for simple async - Like single API calls 4. Beginner friendly - Good starting point for new devs

Why do we use Redux Saga?

Redux Saga is used when we need: 1. Complex async logic handling 2. Features like cancellation of tasks 3. Better performance for intensive async flows 4. Easy testing of asynchronous code

Can we use Saga and Thunk together?

Yes, using Redux Saga and Thunk together in the same project is possible. However, it's generally not recommended. It's better to pick one based on the complexity of asynchronous logic in the app. Using both can make the code harder to understand and maintain.

Conclusion

Both are excellent options for managing asynchronous logic in React applications using Redux. Redux Thunk offers simple solutions using plain functions, while Redux Saga provides more power through generators. One suits smaller apps, while the Other improves readability and testability for larger apps. 

Redux Toolkit Testing aligns with both options. Whether you opt for the simplicity of Thunk or the enhanced capabilities of Saga, Redux Toolkit Testing can streamline and improve your testing processes, contributing to the overall efficiency and reliability of your React application.

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