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Learn how to solve issues with `node-fetch` when handling responses from HTTP POST requests in Node.js. This guide will help you understand errors and how to properly read responses.
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How to Get a Response from async fetch Request in Node.js

When working with HTTP requests in Node.js, you may encounter a situation where your fetch request returns unexpected responses or errors. One common case is when using the node-fetch library for making HTTP POST requests. In this post, we will tackle the common problem of getting responses from async fetch requests, particularly when dealing with JSON and string responses.

The Problem: Fetch Error

Imagine you're developing a Node.js application and using node-fetch to send an HTTP POST request. You encounter the following error:

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

This error typically indicates that the response you're trying to parse as JSON is not valid JSON format. This often happens if the server isn't returning the expected JSON. For example, it might return a simple text string instead.

What You Tried

In your code, you attempted to read the response like this:

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

But faced the error mentioned above. You also considered using:

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

However, this returned [object Promise], signifying that you didn’t wait for it to resolve before logging it.

The Solution: Proper Response Handling

To successfully handle the response from a fetch request, you need to use the await keyword correctly. JavaScript async/await syntax allows you to write asynchronous code that behaves similarly to synchronous code.

Step-by-Step Solution

Await the Response: When you call res.text(), it returns a promise. You need to await this promise to get the actual response.

Modify Your Code: Update the part of your code that logs the response to ensure you're awaiting the promise. Here's how to do it properly:

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

Key Takeaways

Always await promises: Remember that methods like res.text() and res.json() return promises and must be awaited to retrieve the actual value.

Handle errors properly: Wrapping your async code in a try-catch block helps manage errors effectively, making your app more reliable.

Understand response formats: Ensure your server returns the response in the expected format (JSON, string, etc.), as mismatched expectations lead to errors.

Conclusion

Understanding how to properly handle async fetch requests in Node.js using node-fetch will greatly improve your HTTP request logic. By following the steps outlined above, you can avoid common pitfalls related to response errors and successfully work with data returned from your requests. Keep experimenting with async functions, and ensure you are always waiting for promises to resolve to get the results you need!