Wt (pronounced ''"witty"'') is an

open-source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use and view the source code, design documents, or content of the product. The open source model is a decentrali ...

widget-centric

web framework A web framework (WF) or web application framework (WAF) is a software framework that is designed to support the development of web applications including web services, web resources, and web APIs. Web frameworks provide a standard way to build a ...

for the C++ programming language. It has an

API An application programming interface (API) is a connection between computers or between computer programs. It is a type of software interface, offering a service to other pieces of software. A document or standard that describes how to build ...

resembling that of Qt framework (although it was developed with Boost, and is incompatible when mixed with Qt), also using a widget-tree and an event-driven signal/slot system. The Wt's design goal is to benefit from the

stateful In information technology and computer science, a system is described as stateful if it is designed to remember preceding events or user interactions; the remembered information is called the state of the system. The set of states a system can oc ...

component Component may refer to: In engineering, science, and technology Generic systems *System components, an entity with discrete structure, such as an assembly or software module, within a system considered at a particular level of analysis * Lumped e ...

model used in desktop-applications APIs, applied to

web development Web development is the work involved in developing a website for the Internet (World Wide Web) or an intranet (a private network). Web development can range from developing a simple single static page of plain text to complex web applications, ...

—instead of the traditional MVC (model–view–controller) design pattern. So rather than using MVC at the level of a

web page A web page (or webpage) is a World Wide Web, Web document that is accessed in a web browser. A website typically consists of many web pages hyperlink, linked together under a common domain name. The term "web page" is therefore a metaphor of pap ...

, it is pushed to the level of individual components. While the

library A library is a collection of Book, books, and possibly other Document, materials and Media (communication), media, that is accessible for use by its members and members of allied institutions. Libraries provide physical (hard copies) or electron ...

uses a desktop

software development process In software engineering, a software development process or software development life cycle (SDLC) is a process of planning and managing software development. It typically involves dividing software development work into smaller, parallel, or s ...

, it does support some

web Web most often refers to: * Spider web, a silken structure created by the animal * World Wide Web or the Web, an Internet-based hypertext system Web, WEB, or the Web may also refer to: Computing * WEB, a literate programming system created by ...

-specific features, including: *

Semantic URL Clean URLs (also known as user-friendly URLs, pretty URLs, search-engine–friendly URLs or RESTful URLs) are web addresses or Uniform Resource Locators (URLs) intended to improve the usability and accessibility of a website, web application, or w ...

s * Navigation of browser's history One of the unique features of Wt is its abstraction layer of the browser rendering model. The library uses

Ajax Ajax may refer to: Greek mythology and tragedy * Ajax the Great, a Greek mythological hero, son of King Telamon and Periboea * Ajax the Lesser, a Greek mythological hero, son of Oileus, the king of Locris * Ajax (play), ''Ajax'' (play), by the an ...

for communicating with browsers compatible with it, while using plain

HTML Hypertext Markup Language (HTML) is the standard markup language for documents designed to be displayed in a web browser. It defines the content and structure of web content. It is often assisted by technologies such as Cascading Style Sheets ( ...

form Form is the shape, visual appearance, or configuration of an object. In a wider sense, the form is the way something happens. Form may also refer to: *Form (document), a document (printed or electronic) with spaces in which to write or enter dat ...

post-backs for other

user agent On the Web, a user agent is a software agent responsible for retrieving and facilitating end-user interaction with Web content. This includes all web browsers, such as Google Chrome and Safari A safari (; originally ) is an overland jour ...

s. Using a progressive bootstrap-method, the

user interface In the industrial design field of human–computer interaction, a user interface (UI) is the space where interactions between humans and machines occur. The goal of this interaction is to allow effective operation and control of the machine fro ...

is rendered as a plain HTML

document A document is a writing, written, drawing, drawn, presented, or memorialized representation of thought, often the manifestation of nonfiction, non-fictional, as well as fictional, content. The word originates from the Latin ', which denotes ...

first, then, provided its support in browser, it is automatically upgraded to use

for increased interactivity. In this way, Wt is by definition: * The only

server Server may refer to: Computing *Server (computing), a computer program or a device that provides requested information for other programs or devices, called clients. Role * Waiting staff, those who work at a restaurant or a bar attending custome ...

-side

framework A framework is a generic term commonly referring to an essential supporting structure which other things are built on top of. Framework may refer to: Computing * Application framework, used to implement the structure of an application for an op ...

implementing the strategy of

progressive enhancement Progressive enhancement is a strategy in web design that puts emphasis on web content first, allowing everyone to access the basic content and functionality of a web page, while users with additional browser features or faster Internet access r ...

automatically; * The only Ajax framework with

search engine optimization Search engine optimization (SEO) is the process of improving the quality and quantity of Web traffic, website traffic to a website or a web page from web search engine, search engines. SEO targets unpaid search traffic (usually referred to as ...

(SEO) qualities. Because of the popularity of C/C++ in

embedded system An embedded system is a specialized computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is e ...

environments, Wt is often used in such devices and (as a consequence) has been highly optimized for

performance A performance is an act or process of staging or presenting a play, concert, or other form of entertainment. It is also defined as the action or process of carrying out or accomplishing an action, task, or function. Performance has evolved glo ...

Major features

* Automatic

graceful degradation Fault tolerance is the ability of a system to maintain proper operation despite failures or faults in one or more of its components. This capability is essential for high-availability, mission-critical, or even life-critical systems. Fault to ...

and

* Supports server-initiated events (

Comet A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding ...

) * A unified rendering API ( SVG, the HTML5

canvas element The HTML canvas element allows for dynamic, scriptable rendering of 2D shapes and bitmap images. Introduced in HTML5, it is a low level, procedural model that updates a bitmap. The element also helps in making 2D games. While the element ...

VML VML may refer to: * Varnish microlamination, a dating methodology * Vastus medialis longus, the muscle * Vector Markup Language, an obsolete XML-based file format for two-dimensional vector graphics * Veturimiesten liitto, a trade union represen ...

) *

Client Client(s) or The Client may refer to: * Client (business) * Client (computing), hardware or software that accesses a remote service on another computer * Customer or client, a recipient of goods or services in return for monetary or other valuable ...

- and

-side validation * Contains various

security Security is protection from, or resilience against, potential harm (or other unwanted coercion). Beneficiaries (technically referents) of security may be persons and social groups, objects and institutions, ecosystems, or any other entity or ...

features to avoid

Cross-site scripting Cross-site scripting (XSS) is a type of security vulnerability that can be found in some web applications. XSS attacks enable attackers to inject client-side scripts into web pages viewed by other users. A cross-site scripting vulnerability may be ...

and

Cross-site request forgery Cross-site request forgery, also known as one-click attack or session riding and abbreviated as CSRF (sometimes pronounced ''sea-surf'') or XSRF, is a type of malicious exploit of a website or web application where unauthorized commands are submit ...

(CSRF) vulnerabilities * Includes a compact C++ ORM-layer ("Wt::Dbo") * Uses the

WebSocket WebSocket is a computer communications protocol, providing a full-duplex, simultaneous two-way communication channel over a single Transmission Control Protocol (TCP) connection. The WebSocket protocol was standardized by the Internet Engineering ...

networking protocol, if available, for

Client–server model The client–server model is a distributed application structure that partitions tasks or workloads between the providers of a resource or service, called servers, and service requesters, called clients. Often clients and servers communicate ov ...

of communication, with fallbacks to Ajax or plain

rendering For a more detailed overview, see the Features section of official website.

Code example

The

"Hello, World!" program A "Hello, World!" program is usually a simple computer program that emits (or displays) to the screen (often the Console application, console) a message similar to "Hello, World!". A small piece of code in most general-purpose programming languag ...

in Wt: #include #include #include #include #include #include /* * A simple hello world application class which demonstrates how to react * to events, read input, and give feed-back. */ class HelloApplication : public Wt::WApplication ; /* * The env argument contains information about the new session, and * the initial request. It must be passed to the WApplication * constructor so it is typically also an argument for your custom * application constructor. */ HelloApplication::HelloApplication(const Wt::WEnvironment& env) : WApplication(env) void HelloApplication::greet() int main(int argc, char **argv)

References

External links

{{DEFAULTSORT:Wt - Web Toolkit Ajax (programming) Articles with example C++ code Rich web application frameworks Web development software Web frameworks Web server software

Major features

Code example

See also

References

External links