Avoid inline code and logic | Write Clean Code - Part 2

In our previous post we wrote how to reduce if else in php in order to write the clean. Today, I am going to show you how to avoid inline code and logic in PHP.

Consider, you have a piece of code, that will allow a user to upload the image into your system. The overall process is-

• A user can able to upload an image
• The code will check the extension of the uploaded image
• Cross-check whether is uploaded image extension is allowed to upload or not
• Allow to upload if the previous condition is pass, otherwise, show the error

I am sure, there are many ways to do that. I have a piece of code already that has written by one developer. Let’s review the code-

    public function uploadFile()
    {
    	$allowedFileExtensions = ['jpg', 'gif'];

    	// This will upload by user. This code is only to demonostrate
    	$fileName = 'nature.jpg';

    	$allowedFileToUpload = in_array(strtolower(end(explode('.', $fileName))), $allowedFileExtensions) ? true : flase;

    	if ( $allowedFileToUpload) {
    		# Upload your image
    	} else {
    		# Error and Redirect
    	}
    }

This code works fine, without having any issue. But if you look into the code, I feel this $allowedFileToUpload = in_array(strtolower(end(explode('.', $fileName))), $allowedFileExtensions) ? true : flase; line is kind of confusing or hard to read. I strongly believe this line can make more readable.

Let’s do refactor

After reviewing the code, I come out with the following refactoring. Here is my idea-

    public function uploadFile()
    {
    	$allowedFileExtensions = ['jpg', 'gif'];

    	// This will upload by user. This code is only to demonostrate
    	$fileName = 'nature.jpg';

    	$fileToPath = explode('.', $fileName);
    	$fileExtension = strtolower(end($fileToPath));

    	if ( ! in_array($fileExtension, $allowedFileExtensions)) {
    		// Error and Redirect
    	}

    	// Upload the file
    }

My idea is to make each line more meaningful. Now you can see the lines I have used to have its own purpose. At least, each line describes it’s own task.

Feel free to share your idea also to improve this code better.

Thank you.