Screenshots

An application that, given a URL, will take a screenshot of the page and save it to a file.

Example Screenshot

Usage

To request a screenshot of a page, make a GET request to the application with the URL of the page you want to screenshot as the url parameter:

GET /?url=https://jamesg.blog

This will return an image file of the top of the viewport.

Process

When a request is received, this application:

1. Validates the URL to make sure the host name is in an allowed list of domains.
2. Checks if a screenshot of the page has already been taken.
3. If a screenshot has already been taken, it is returned.
4. If a screenshot has not been taken, the page is loaded in a headless browser and a screenshot is taken.
5. The screenshot is saved to a file.
6. The screenshot is returned to the user.

This application uses Puppeteer to take the screenshot.

Installation

To install this project, clone the repository and run npm install:

git clone https://github.com/capjamesg/screenshots
cd screenshots
npm install

Next, set a CACHE_CLEAR_KEY environment variable to a secret string. This will be the key that is used to clear the cache for an image. For example:

export CACHE_CLEAR_KEY=1234567890

Next, open the screenshot.js file and add the domains you want to allow screenshots of to the allowedDomains array. For example:

const allowedDomains = [
    "example.com"
];

To run the project, execute the following command:

node screenshot.js

This will run the project at http://localhost:9005.

Technologies Used

• Puppeteer
• Express
• Node.js

License

This application is licensed under an MIT No Attribution license. See the LICENSE file for more information.

Contributors

• capjamesg