How to Download View-Only PDFs from Google Drive Using Browser Console | Developer’s Guide

Discover a powerful JavaScript solution to download view-only PDFs and protected documents from Google Drive using browser developer tools. This comprehensive guide provides a step-by-step approach with ready-to-use code.

Introduction

Many users face challenges when trying to download protected or view-only PDFs from Google Drive. While these restrictions are put in place for document security, there are legitimate scenarios where you might need to download these documents for offline access or archival purposes. This article presents a developer-friendly approach using browser console commands.

The JavaScript Solution

The following code provides a robust solution for downloading protected images that make up a view-only PDF. It handles automatic scrolling, ensures all images are captured, and manages the download process efficiently.

async function downloadImages() {
    const elements = document.getElementsByTagName("img");
    const delay = ms => new Promise(resolve => setTimeout(resolve, ms));
    
    // Function to check if an image is in viewport
    function isInViewport(element) {
        const rect = element.getBoundingClientRect();
        return (
            rect.top >= 0 &&
            rect.left >= 0 &&
            rect.bottom <= (window.innerHeight || document.documentElement.clientHeight) &&
            rect.right <= (window.innerWidth || document.documentElement.clientWidth)
        );
    }

    // Function to scroll to element
    function scrollToElement(element) {
        element.scrollIntoView({ behavior: 'smooth', block: 'center' });
    }

    // Function to download single image
    async function downloadImage(img, index) {
        return new Promise((resolve) => {
            const canvasElement = document.createElement('canvas');
            const con = canvasElement.getContext("2d");
            canvasElement.width = img.width;
            canvasElement.height = img.height;
            con.drawImage(img, 0, 0, img.width, img.height);
            
            canvasElement.toBlob((blob) => {
                const url = URL.createObjectURL(blob);
                const a = document.createElement('a');
                a.href = url;
                a.download = `image${index}.jpg`;
                a.click();
                URL.revokeObjectURL(url);
                resolve();
            }, 'image/jpeg', 1.0);
        });
    }

    for (let i = 0; i < elements.length; i++) {
        const img = elements[i];
        if (/^blob:/.test(img.src)) {
            // Scroll to image if not in viewport
            if (!isInViewport(img)) {
                scrollToElement(img);
                // Wait for scroll and image to load
                await delay(1000);
            }
            
            // Ensure image is fully loaded
            if (!img.complete) {
                await new Promise(resolve => {
                    img.onload = resolve;
                    img.onerror = resolve;
                });
            }
            
            // Download the image
            await downloadImage(img, i);
            
            // Small delay between downloads to prevent browser throttling
            await delay(500);
        }
    }
    
    console.log('All images have been processed!');
}

// Start the download process
downloadImages().catch(error => console.error('Error:', error));

How the Code Works

1. Image Detection: Identifies all images on the page using document.getElementsByTagName(“img”)
2. Viewport Management: Implements smart scrolling to ensure all images are loaded
3. Canvas Processing: Converts images to downloadable format using HTML5 Canvas
4. Sequential Downloads: Manages downloads with proper timing to prevent browser throttling

How to Use This Solution

1. Open the view-only PDF in Google Drive
2. Press F12 to open Developer Tools
3. Navigate to the Console tab
4. Paste the provided code
5. Press Enter to execute
6. Wait for all images to download

Important Considerations

• This method works best with modern browsers (Chrome, Firefox, Edge)
• Ensure stable internet connection during the process
• Be aware of document copyright and usage rights
• Consider file size and browser memory limitations