File uploads in Laravel - Mini Project: Build & Apply

File Uploads in Laravel

📖 Scenario: You are building a simple Laravel web app where users can upload profile pictures. The app needs to accept image files and store them safely on the server.

🎯 Goal: Build a Laravel file upload feature that accepts an image file from a form, validates it, and saves it to the storage/app/public directory.

📋 What You'll Learn

Create a form with a file input named profile_picture

Add a validation rule to accept only image files

Store the uploaded file in the public disk

Return the stored file path after upload

💡 Why This Matters

🌍 Real World

File uploads are common in web apps for profile pictures, documents, and media. Handling uploads securely and correctly is essential.

💼 Career

Backend developers often implement file upload features. Knowing Laravel's file handling and validation is important for building real-world applications.

1

Create the file upload form

Create a Blade view file with a form that uses POST method and enctype="multipart/form-data". Add a file input with the name profile_picture and a submit button.

Laravel

    @csrf
    
    

Hint

Remember to set enctype="multipart/form-data" on the form to allow file uploads.

2

Add route and controller method

In routes/web.php, add a POST route for /upload that uses UploadController@store. Then create UploadController with a store method stub.

Laravel

use App\Http\Controllers\UploadController;

// Add POST route for /upload
// Your code here

// Create UploadController with store method stub
// Your code here

Hint

Use Route::post with the controller class and method array syntax.

3

Validate and store the uploaded file

In the store method, validate the profile_picture input to accept only image files. Then store the file on the public disk using store('profile_pictures', 'public'). Save the returned path in a variable called path.

Laravel

class UploadController extends Controller
{
    public function store(Request $request)
    {
        // Validate profile_picture as image
        // Store file on public disk in profile_pictures folder
        // Save path to $path
        // Your code here
    }
}

Hint

Use Laravel's validate method and the image rule to accept only images.

4

Return the stored file path

Complete the store method by returning the stored file path $path as a plain string response using return $path;.

Laravel

class UploadController extends Controller
{
    public function store(Request $request)
    {
        $request->validate([
            'profile_picture' => 'required|image'
        ]);

        $path = $request->file('profile_picture')->store('profile_pictures', 'public');

        // Return the stored file path
        // Your code here
    }
}

Hint

Use return $path; to send back the stored file path as a response.

Practice

1. In Laravel, which method is used to check if a file was uploaded in a request?

easy

A. $request->isFile('file')

B. $request->hasFile('file')

C. $request->checkFile('file')

D. $request->fileExists('file')

Solution

1. Step 1: Identify Laravel method to check file upload

   Laravel provides hasFile to verify if a file was uploaded in the request.

2. Step 2: Compare options with Laravel documentation

   Only hasFile is the correct method; others do not exist in Laravel.

3. Final Answer:

   $request->hasFile('file') -> Option B

4. Quick Check:

   Check file upload with hasFile() = D [OK]

Hint: Use hasFile() to check uploaded files quickly [OK]

Common Mistakes:

• Using non-existent methods like fileExists()
• Confusing hasFile() with file() method
• Not checking if file exists before processing

2. Which HTML form attribute is required to upload files in Laravel?

easy

A. enctype="multipart/form-data"

B. method="post"

C. action="upload.php"

D. type="file"

Solution

1. Step 1: Identify form attribute for file uploads

   File uploads require the form to have enctype="multipart/form-data" to send file data properly.

2. Step 2: Check other attributes

   method="post" is needed but not enough alone; type="file" is for input, not form; action defines URL, not upload encoding.

3. Final Answer:

   enctype="multipart/form-data" -> Option A

4. Quick Check:

   Form encoding for files = B [OK]

Hint: Always set enctype to multipart/form-data for file uploads [OK]

Common Mistakes:

• Omitting enctype attribute
• Using GET method instead of POST
• Confusing input type with form attribute

3. What will be the output of this Laravel code snippet after uploading a file named photo.jpg?

$path = $request->file('photo')->store('images');
return $path;

medium

A. "photo.jpg"

B. "images/photo.jpg"

C. "/storage/images/photo.jpg"

D. "images/unique_generated_name.jpg"

Solution

1. Step 1: Understand store() method behavior

   The store() method saves the file in the specified folder with a unique generated filename to avoid overwriting.

2. Step 2: Analyze returned path

   The returned path includes the folder and the unique filename, not the original filename or full storage path.

3. Final Answer:

   "images/unique_generated_name.jpg" -> Option D

4. Quick Check:

   store() returns folder + unique filename = A [OK]

Hint: store() saves file with unique name, returns folder plus new filename [OK]

Common Mistakes:

• Assuming original filename is kept
• Expecting full storage path returned
• Confusing store() with move() method

4. Identify the error in this Laravel file upload code:

if ($request->hasFile('avatar')) {
  $file = $request->file('avatar');
  $file->move('uploads');
}

medium

A. Missing second argument for move() method

B. Incorrect method to check file existence

C. move() should be called on $request, not $file

D. No error, code is correct

Solution

1. Step 1: Review move() method signature

   The move() method requires two arguments: destination path and filename.

2. Step 2: Check code arguments

   Only one argument ('uploads') is given; filename is missing, causing an error.

3. Final Answer:

   Missing second argument for move() method -> Option A

4. Quick Check:

   move() needs path and filename = C [OK]

Hint: move() needs destination path and filename both [OK]

Common Mistakes:

• Calling move() with only one argument
• Confusing hasFile() with fileExists()
• Calling move() on request instead of file

5. You want to upload multiple images and save their paths in the database. Which Laravel approach correctly handles multiple file uploads in a request named photos?

hard

A. if ($request->hasFile('photos')) {
$path = $request->file('photos')->store('gallery');
Photo::create(['path' => $path]);
}

B. $photos = $request->file('photos');
$photos->store('gallery');
Photo::create(['path' => $photos]);

C. foreach ($request->file('photos') as $photo) {
$path = $photo->store('gallery');
Photo::create(['path' => $path]);
}

D. $path = $request->file('photos')->move('gallery');
Photo::create(['path' => $path]);

Solution

1. Step 1: Understand multiple file upload handling

   Multiple files come as an array; you must loop through each file to store and save paths.

2. Step 2: Analyze options for correct looping and storing

   foreach ($request->file('photos') as $photo) {
     $path = $photo->store('gallery');
     Photo::create(['path' => $path]);
   }

   loops over each file, stores it, and saves path correctly. Others treat files as single or misuse methods.

3. Final Answer:

   Loop through each file, store, and save path -> Option C

4. Quick Check:

   Multiple files need foreach loop = A [OK]

Hint: Use foreach to handle multiple uploaded files individually [OK]

Common Mistakes:

• Treating multiple files as single file
• Not looping through file array
• Calling store() on file array directly