Offline website in Progressive Web Apps using Service worker.

The aim of the bachelor thesis is to describe and elaborate the PWA (Progressive Web Apps) technology and the possibilities of using Service worker in the creation of so-called progressive web applications. PWA is a technology that enables the creation of a web application that uses a web browser and at the same time allows a so-called cross-platform approach. Service worker is a JavaScript asset that acts as a proxy server and is therefore a necessary component in the creation of progressive web applications. The created application then has the properties of a classic web page, but the main advantage is also the properties of a native application. The PWA technology uses HTML and CSS to create the appearance of the application and JavaScript to implement the Service worker. In the theoretical part, the author will focus mainly on the introduction of the PWA technology itself, advantages and disadvantages of using PWA, implementation of Service worker using JavaScript, description of individual components and general syntax that is necessary for creating an application. In the practical part, a progressive web application will be created using Service worker to demonstrate the possibilities, features and advantages or disadvantages that PWA technology brings. The practical part will also include an exploration of the prevalence of PWAs today in relation to conventional websites.