Troubleshooting Login Endpoint Differences Between Local Development and Render Deployment

How can I troubleshoot differences in API responses between my local environment and Render when accessing a login endpoint on my app’s backend? Despite verifying environmental variables and CORS configurations, I encounter discrepancies, such as receiving an undefined user data and no token upon successful login on Render, whereas it works fine locally.
Here’s an example of the response I receive locally:

json

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{
  "data": {
    "success": true,
    "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...",
    "user": { ... }
  },
  "status": 200,
  ...
}

ChatGPT

Based on the provided data and code, it seems that the issue lies in the response received from the login API endpoint when deployed on Render compared to the local environment. Here’s a refined version of your question to seek expert advice:


Question: I’m encountering discrepancies in the response from my login API endpoint between my local development environment and when deployed on Render. When I log in locally, I receive a successful response containing user data and a JWT token, as expected. However, when I log in on Render, the response is empty, with no user data or token.

Here’s an example of the response I receive locally:

json

Copy code

{
  "data": {
    "success": true,
    "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...",
    "user": { ... }
  },
  "status": 200,
  ...
}

And here’s the response I receive on Render:

json

Copy code

{
  "data": "",
  "status": 200,
  ...
}

I’ve verified that environmental variables and CORS configurations are correct. Below is the code snippet for the login API endpoint and the sendToken function responsible for sending the response:

typescript

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// Login API endpoint
export const loginUser = catchAsyncErrors(
  async (req: Request, res: Response, next: NextFunction) => {
    const { email, password } = req.body;

    // Checks if email and password is entered by user
    if (!email || !password) {
      return next(new ErrorHandler("Please enter email & password", 400));
    }

    // Finding user in database
    const user = await User.findOne({ email }).select("+password");

    if (!user) {
      return next(new ErrorHandler("User not registered", 401));
    }

    // Checks if password is correct or not
    const isPasswordMatched = await user.comparePassword(password);

    if (!isPasswordMatched) {
      return next(new ErrorHandler("Wrong password", 401));
    }

    sendToken(user, 200, res);
  }
);

// sendToken function
const sendToken = (
  user: UserDocument,
  statusCode: number,
  res: Response
): void => {
  try {
    // Create Jwt token
    const token = (user as any).getJwtToken();

    // Options for setting cookie
    const options = {
      expires: new Date(Date.now() + 1000 * 60 * 60 * 24),
      httpOnly: true,
    };

    res.status(statusCode).cookie("token", token, options).json({
      success: true,
      token,
      user,
    });
  } catch (error) {
    // Handle any errors that occur
    console.error("Error in sendToken:", error);
    res.status(500).json({ success: false, message: "Internal server error" });
  }
};

What could be causing this discrepancy in the response, and how can I ensure consistent behavior between my local development environment and Render deployment?

Hi there,

Have you tried something as simple as adding debug log statements to your code to see where the differences may appear?

Regards,

Keith
Render Support, UTC+10 :australia: