How to Prevent Duplicate Function Calls in React: The Optimized Approach

Learn how to effectively manage asynchronous calls in React functional components to avoid duplicate calls even with multiple dependencies in useEffect.
---

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Function gets called even after setting global state to prevent it

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
How to Prevent Duplicate Function Calls in React: The Optimized Approach

In the world of React development, handling asynchronous operations efficiently is crucial, especially when it comes to ensuring that a function does not get called multiple times unnecessarily. One common scenario you may encounter is when a function calls an API repeatedly, even though you have implemented checks to avoid this. If you're facing the issue of duplicate API calls in a functional component, you're not alone. In this guide, we will explore a situation where functions are getting invoked despite precautions, and provide a clear solution to this problem.

The Problem

Imagine you have a functional component that handles user referrals. You want to ensure that your API call to save referral data only occurs when certain conditions are met. However, due to the component’s rerendering when state changes, your API function is firing multiple times, potentially resulting in duplicate data being stored.

Code Snippet

Here’s a simplified version of what your component might look like:

[[See Video to Reveal this Text or Code Snippet]]

The troubling part is that despite adding the condition !referralUserSaved, your API function still gets triggered multiple times.

The Underlying Cause

The issue arises because:

Your dependencies in the useEffect are causing rerenders based on changes to their values. Each time they change, the effect runs again.

The API call you're making is asynchronous. Therefore, by the time the call is processed, the referralUserSaved condition might change, leading to multiple submissions.

The Solution

To remedy this situation, we need to set up a way to control when the function executes more strictly. We can utilize a fetching state to manage whether the function is currently processing. The following sections break down how to implement this solution effectively.

1. Introduce a Fetching State

By introducing a fetching state, we can prevent the function from executing while an API call is in progress. Here’s how you can implement it:

[[See Video to Reveal this Text or Code Snippet]]

2. Modify the API Call Function

Ensure that your function to save referral installations checks the fetching state before proceeding. Here’s how that function might look:

[[See Video to Reveal this Text or Code Snippet]]

3. Update the Effect Hook

Finally, update your useEffect to include this fetching state so that it doesn’t allow further calls when one is already in process:

[[See Video to Reveal this Text or Code Snippet]]

Summary

By managing the fetching state, we have created a guard that ensures the API call can only be executed when it’s not already in process, effectively preventing duplicate calls.

Always add necessary checks before calling your API.

If using asynchronous calls, manage their state effectively.

Aim to have comprehensive dependencies in the useEffect to avoid unnecessary executions.

Conclusion

In summary, to effectively manage API calls in React and prevent duplicate data, it’s essential to handle state carefully. Utilize a fetching state to ensure your function only proceeds when appropriate conditions are met. This strategy not only prevents performance issues but also keeps your user data clean and accurate.

Engaging in such practices not only refines your codebase but also improves overall application user experience by ensuring data consistency. Implement these suggestions in your future projects, and you’ll notice a marked improvement in how your application handles asynchronous calls.