In web development, a postback is the exchange of information between servers to report a user's action on a website, network, or app.
Technically speaking, a postback is an HTTP POST to the same page that the form is on. In other words, the contents of the form are POSTed back to the same URL as the form. [1]
Postbacks are commonly seen in edit forms, where the user introduces information in a form and hits "save" or "submit", causing a postback. The server then refreshes the same page using the information it has just received.
Postbacks are most commonly discussed in relation to JSF and ASP or ASP.NET.
In ASP, a form and its POST action have to be created as two separate pages, resulting in the need for an intermediate page and a redirect if one simply wants to perform a postback. This problem was addressed in ASP.NET with the __doPostBack()
function and an application model that allows a page to perform validation and processing on its own form data.
In JSF, postbacks trigger the full JSF life-cycle, which just like ASP.NET performs conversion and validation of the form data that was included in the postback. Various utility methods are present in the JSF API to programmatically check if a given request is a postback or not.
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 over a computer network on separate hardware, but both client and server may be on the same device. A server host runs one or more server programs, which share their resources with clients. A client usually does not share any of its resources, but it requests content or service from a server. Clients, therefore, initiate communication sessions with servers, which await incoming requests. Examples of computer applications that use the client–server model are email, network printing, and the World Wide Web.
Microsoft Access is a database management system (DBMS) from Microsoft that combines the relational Access Database Engine (ACE) with a graphical user interface and software-development tools. It is a member of the Microsoft 365 suite of applications, included in the Professional and higher editions or sold separately.
Server-side scripting is a technique used in web development which involves employing scripts on a web server which produces a response customized for each user's (client's) request to the website. Scripts can be written in any of a number of server-side scripting languages that are available. Server-side scripting is distinguished from client-side scripting where embedded scripts, such as JavaScript, are run client-side in a web browser, but both techniques are often used together. The alternative to either or both types of scripting is for the web server itself to deliver a static web page.
The World Wide Web is an information system that enables content sharing over the Internet through user-friendly ways meant to appeal to users beyond IT specialists and hobbyists. It allows documents and other web resources to be accessed over the Internet according to specific rules of the Hypertext Transfer Protocol (HTTP).
Jakarta EE, formerly Java Platform, Enterprise Edition and Java 2 Platform, Enterprise Edition (J2EE), is a set of specifications, extending Java SE with specifications for enterprise features such as distributed computing and web services. Jakarta EE applications are run on reference runtimes, which can be microservices or application servers, which handle transactions, security, scalability, concurrency and management of the components they are deploying.
In computer networking, a proxy server is a server application that acts as an intermediary between a client requesting a resource and the server providing that resource. It improves privacy, security, and possibly performance in the process.
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 used by attackers to bypass access controls such as the same-origin policy. During the second half of 2007, XSSed documented 11,253 site-specific cross-site vulnerabilities, compared to 2,134 "traditional" vulnerabilities documented by Symantec. XSS effects vary in range from petty nuisance to significant security risk, depending on the sensitivity of the data handled by the vulnerable site and the nature of any security mitigation implemented by the site's owner network.
A web application is application software that is created with web technologies and runs via a web browser. Web applications emerged during the late 1990s and allowed for the server to dynamically build a response to the request, in contrast to static web pages.
Jakarta Faces, formerly Jakarta Server Faces and JavaServer Faces (JSF) is a Java specification for building component-based user interfaces for web applications. It was formalized as a standard through the Java Community Process as part of the Java Platform, Enterprise Edition. It is an MVC web framework that simplifies the construction of user interfaces (UI) for server-based applications by using reusable UI components in a page.
Web development is the work involved in developing a website for the Internet or an intranet. Web development can range from developing a simple single static page of plain text to complex web applications, electronic businesses, and social network services. A more comprehensive list of tasks to which Web development commonly refers, may include Web engineering, Web design, Web content development, client liaison, client-side/server-side scripting, Web server and network security configuration, and e-commerce development.
A dynamic web page is a web page constructed at runtime, as opposed to a static web page, delivered as it is stored.
A webform, web form or HTML form on a web page allows a user to enter data that is sent to a server for processing. Forms can resemble paper or database forms because web users fill out the forms using checkboxes, radio buttons, or text fields. For example, forms can be used to enter shipping or credit card data to order a product, or can be used to retrieve search results from a search engine.
Microsoft InfoPath is a discontinued software application for designing, distributing, filling and submitting electronic forms containing structured data. Microsoft initially released InfoPath as part of the Microsoft Office 2003 family. The product features a WYSIWYG form designer in which the various controls are bound to data, represented separately as a hierarchical tree view of folders and data fields.
RichFaces was an open source Ajax-enabled component library for JavaServer Faces, hosted by JBoss. It allows easy integration of Ajax capabilities into enterprise application development. It reached its end-of-life in June 2016.
In computing, POST is a request method supported by HTTP used by the World Wide Web. By design, the POST request method requests that a web server accepts the data enclosed in the body of the request message, most likely for storing it. It is often used when uploading a file or when submitting a completed web form.
Cross-site request forgery, also known as one-click attack or session riding and abbreviated as CSRF or XSRF, is a type of malicious exploit of a website or web application where unauthorized commands are submitted from a user that the web application trusts. There are many ways in which a malicious website can transmit such commands; specially-crafted image tags, hidden forms, and JavaScript fetch or XMLHttpRequests, for example, can all work without the user's interaction or even knowledge. Unlike cross-site scripting (XSS), which exploits the trust a user has for a particular site, CSRF exploits the trust that a site has in a user's browser. In a CSRF attack, an innocent end user is tricked by an attacker into submitting a web request that they did not intend. This may cause actions to be performed on the website that can include inadvertent client or server data leakage, change of session state, or manipulation of an end user's account.
ASP.NET Web Forms is a web application framework and one of several programming models supported by the Microsoft ASP.NET technology. Web Forms applications can be written in any programming language which supports the Common Language Runtime, such as C# or Visual Basic. The main building blocks of Web Forms pages are server controls, which are reusable components responsible for rendering HTML markup and responding to events. A technique called view state is used to persist the state of server controls between normally stateless HTTP requests.
A web shell is a shell-like interface that enables a web server to be remotely accessed, often for the purposes of cyberattacks. A web shell is unique in that a web browser is used to interact with it.
The following outline is provided as an overview of and topical guide to web design and web development, two very related fields: