index.html

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>File Upload</title>
    <script src="https://cdn.jsdelivr.net/npm/axios/dist/axios.min.js"></script>
</head>

<body>
    <input type="file" id="fileInput" />
    <button onclick="uploadFile()">Upload</button>

    <div>
        <progress id="uploadProgress" value="0" max="100" style="width: 100%"></progress>
        <span id="uploadPercentage">0%</span>
    </div>

    <script>
        const uploadFile = async () => {
            const fileInput = document.getElementById('fileInput')
            // เพิ่ม 2 อันนี้เข้ามา
            const progressBar = document.getElementById('uploadProgress')
            const uploadPercentageDisplay = document.getElementById('uploadPercentage')

            const formData = new FormData()
            formData.append('file', fileInput.files[0])

            if (!fileInput.files.length) {
                return alert('Please choose a file to upload')
            }

            try {
                const response = await axios
                    .post('http://localhost:8000/upload', formData, {
                        headers: {
                            'Content-Type': 'multipart/form-data',
                        },
                        onUploadProgress: function (progressEvent) {
                            // เพิ่ม update progress กลับเข้า UI ไป
                            const percentCompleted = Math.round((progressEvent.loaded * 100) / progressEvent.total)
                            progressBar.value = percentCompleted
                            uploadPercentageDisplay.innerText = `${percentCompleted}%`
                        },
                    })
            } catch (error) {
                console.log('error', error)
                alert('Error uploading file')
            }
        }
    </script>
</body>

</html>