Bring the power and speed of RAD to your Web application development with WebSnap

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1 Bring the power and speed of RAD to your Web application development with WebSnap by Nick Hodges, HardThink, Incorporated Introduction Taking the best of today s web technologies, Delphi 6 introduces a next-generation web application framework called WebSnap that brings the strengths of Rapid Application Development (RAD) to web development. WebSnap brings Delphi into today s web team as the business object foundry of the company integrating back-end business processes as easy-touse scriptable objects. WebSnap enables Delphi to build the scriptable business objects, database driven web pages, and backend servers that are integral to a successful, dynamic web site. WebSnap integrates with the Borland Implementation Platform to make a company s web site part of a total enterprise strategy. Delphi 6 presents a development platform designed to help integrate the broad-ranging nature of today s enterprise IT departments. Its native support for Web Services ties into an open database architecture to connect the entire supply chain with a company s internal data stores. CORBA and Borland AppServer integration brings enterprise application services into the solution, presenting the opportunity to interconnect all Table of Contents Introduction 1 Benefits 2 A Look at the Technology 5 Scenario 8 Conclusion 10 levels of a company s IT infrastructure integrating the business processes of the entire enterprise into the web site. All this is accomplished in an open-standards development environment that is transparently adaptable to common web servers through its support for ISAPI, NSAPI, CGI, and Apache modules. WebSnap provides a web site with the power, scalability, ease of use, and quick time-to-market needed in today s environment. All types of businesses face this challenge, from manufacturers

2 to intellectual content producers. The Delphi 6 WebSnap technology provides a perfect solution for businesses looking for high return on investment, open standards to avoid vendor lockin, powerful tools, and quick development cycles. No business can afford to be caught flat-footed in designing web applications the Internet is simply moving too fast. WebSnap is designed to keep a business on its toes with fast development times, access to current technology, and flexibility in application design. Benefits WebSnap and Delphi integrate seamlessly into the web development process In the early stages of the Worldwide Web, web site development was a relatively simple process, often involving nothing more than the management of a hierarchy of HTML pages. Dynamic content was accomplished via CGI programming in PERL or some other scripting language. As the Internet has grown, web development has become a more complex process involving many different skills, platforms, operating systems, and architectures. A web development team often consists of graphics designers, HTML and script coders, database administrators, COM/CORBA developers, and software engineers. WebSnap brings the fast productivity of a RAD platform to this environment, enhancing the team s performance and capabilities. WebSnap leverages existing team skills and reduces training costs by easily integrating into the web development paradigm. Team productivity is enhanced as WebSnap makes the division of development labor more clearly defined between the business object developers and the scripting engineers. Maintenance costs are reduced as the web site's appearance evolves. Changes to the layout or design of the web site are completely transparent to the WebSnap objects. Development on either the business objects or the scripting has no impact on the other, resulting in simpler team interaction and reduced development costs. The power of reusable WebSnap objects means that the team needs less code. Less code means reduced time-to-market and fewer maintenance problems. Teams spend more time detailing their own custom logic, and less time worrying over how to use the tools at hand. The WebSnap debug server saves time during testing by easing the process of testing web applications. Taken all together, WebSnap means faster development, lower maintenance costs, and higher performance. WebSnap shortens the supply chain with Web Services Businesses gain time, reduce inventory, and enhance customer responsiveness through automated links with their supply chain Web Services. Delphi 6 provides powerful and simple access to those industry-standard Web Services. WebSnap applications can access the functionality of Web Services to connect easily to partners, distributors, suppliers, and other content producers. WebSnap applications can reach directly into a supplier, distributor, or any partner that publishes facets of its business as a Web service. By aggregating multiple sources of information into a single WebSnap application, a corporate web site can truly become an automated window to the world. Utilize existing RDBMS infrastructure without retooling WebSnap can access corporate data wherever it resides WebSnap allows developers to access data where it resides, thus eliminating the need for costly data migration. Development costs are contained, as data doesn t need to be migrated to a database system accessible by the web development tool. Delphi DataSnap, Borland Database Engine, and dbexpress technologies allow WebSnap applications to effortlessly access corporate data from all major database management systems. Whether your data resides on a server from Oracle, Microsoft, IBM, Informix, InterBase, Sybase, or others, the powerful data access tools and components enable WebSnap applications to reach it. 2

3 Take advantage of your Enterprise development with WebSnap The reliability and scalability of the Borland AppServer and other CORBA systems is easily leveraged within WebSnap. WebSnap developers can use the powerful CORBA integration of Delphi to connect to CORBA servers anywhere on a network. WebSnap applications can leverage the power of existing Enterprise JavaBeans (EJB ) deployed on Borland AppServer. WebSnap applications can easily access enterprise level application functionality across heterogeneous network resources and platforms. WebSnap accesses existing resources, eliminating the need for costly migration or recoding. WebModule technology, application code can be easily transferred between different web servers. WebModules isolate the application s logic into units, separating the code that implements the application and that which handles the web server architecture. Applications originally targeted to one server can easily be moved to another without changes to the existing processes or logic. WebSnap produces standards-based web solutions using industry-standard technologies. HTTP, HTML, Javascript, and ML/SL all are integral to WebSnap. WebSnap applications can be accessed by any client platform that conforms to Internet standards. Because WebSnap applications always return HTML and Javascript to the browser, popular web browsers on any operating system can use WebSnap applications. Rather than utilizing nonstandard solutions such as Active, ActiveForms, or other proprietary technologies, the WebSnap use of standard web protocols and languages presents broadranging compatibility and ensures that investments made today will be valuable tomorrow. Figure 1 -- Overview of a web site based on WebSnap Enjoy vendor freedom with open standards WebSnap supports major web server platforms ISAPI, NSAPI, CGI, and Apache, transparently to the team. Using the WebSnap Preserve existing tool investments seamlessly integrate WebSnap with web site building tools such as DreamWeaver, FrontPage, and NetObjects Fusion. Integrating WebSnap applications into a scripted web site is an easy operation, as WebSnap applications can easily interoperate with existing web site development tools. The tools in use today by web development teams will integrate with WebSnap. Web page designers can use tools such as DreamWeaver, NetObjects Fusion, or FrontPage to build and manage a web site, and the WebSnap teams work can be tied directly into the output of these tools to program the dynamic portion of the web site. WebSnap offers ultra-high-performance solutions Web sites constructed with WebSnap enjoy the highest performance, running at speeds only limited by the server itself. 3

4 Native server extensions for the Microsoft and Netscape platforms, CGI executables, and Apache modules are all compiled with the lightning-fast, award-winning Delphi optimizing compiler. This naturally increases the performance of WebSnap applications over other solutions. This also presents a more robust solution, as WebSnap applications do not rely on external code for executing web site logic. Web teams have total control over the entire application, and thus are better able to address issues as they arise, as opposed to other vendors solutions that may introduce delays while waiting for the vendor to repair problems that impede the team. Conserve development time and resources with WebSnap s components WebSnap comes with a variety of time-saving, preconstructed components for use in common web site activities, such as session management, user security, and others. These components are also easily extensible, making the job of producing a customized web site much simpler. Because WebSnap objects are built to be naturally extendable, they can be enhanced to represent the various business functions and processes required across the enterprise. This flexibility enables developers to introduce their own custom application features to the web site s development. For instance, controls that manage shopping cart functionality, navigation menus, banner advertising, custom links, and other standard web page functions all can be designed and reused within the powerful architecture of WebSnap. Applications/business object developers who create business objects and integrate the back-end processes of the enterprise into the web site Scripting engineers, who will provide the connection between the business objects and the web pages. These individuals will likely work with JavaScript, VBScript, or a similar scripting language HTML designers who lay out and design the web site. They will use tools like DreamWeaver, NetObjects Fusion, or FrontPage Graphic artists who will produce the artwork, graphics, and look and feel of the web site. They will use tools like Adobe Photoshop, etc. Web Team Application Development with WebSnap In the early days of web applications and web site building, a single person with only a few skills was all that was needed to build a web site. Now, professional web sites require a team of specialists, each with their own skills. A web site development team will usually consist of four main groups: Figure 2 - WebSnap integrates Team development 4

5 WebSnap is the framework with which the business object team will integrate the broad-ranging back-end processes of the corporation. Web application development managers will focus on producing new WebSnap objects that will publish the business processes needed by the application. These objects and the capabilities that they provide will be given to the web site s scripting team, who will use them to insert the proper content into the pages created by the graphics and HTML teams. The use of particular HTML files is independent of a WebSnap application WebSnap can simply be a reference to specific files, the content of which may change frequently as the appearance of the web site is revised. Using the file management controls in WebSnap, the application simply inserts dynamic content where it belongs, and WebSnap will seamlessly grab the HTML and incorporate it into the application. A Look at the Technology The power and convenience of WebSnap are a result of the power of the Delphi development environment. Teams can customize the WebSnap framework themselves with custom components and classes that provide specialized content that can be reused across projects. The WebSnap work of producing HTML for an application is done by two sets of components, PageProducers and WebSnap objects: PageProducer Components customizable HTML for the application PageProducer components manage HTML code for single web pages or for portions of a page. There are page producers to produce content based on data, static HTML pages, DataSnap data, ML/SL, and other purposes. As with all the features of WebSnap, PageProducers can be customized to build custom content based on an application s needs. 5 WebSnap Objects scriptable elements of an application WebSnap objects, also called Adapters, define an interface between an application and the server-side scripting. Script only has access to an application via these objects, ensuring that the script does not inadvertently change the data in an application or expose functions that are not intended for public consumption. WebSnap includes several objects to manage commonly required functionality already: logins, user sessions, datasets, and more. Team members will also build custom objects to display data according to an application s needs. WebSnap provides tools for web application management: managing users and user state information, providing logins, and keeping track of data on a per user basis are vital to a good web application. Integrating these services into a WebSnap application is as easy as clicking a mouse. Creating a fullfeatured, professional web application can be done in minutes. Logging in users, maintaining state between HTTP requests, and logging user activity all can be done with a minimum of code through the components supplied with WebSnap. Application Adapter The basic element of the WebSnap framework is the Application Adapter. The Application Adapter provides the basic functionality of the web application by managing the interaction with the features of the Web server itself, such as creation and caching of threads and webmodules. Session Management The key to any professional web application is remembering what the user is doing this is called maintaining state. Because HTTP is a stateless protocol that is, once a request is made and fulfilled, the server forgets all about the client and the client s state a web application must maintain the state of the user itself. WebSnap does this via its SessionsService component. The SessionsService seamlessly maintains a session identification value for each user, making it a simple task to keep track of each

6 user as he or she makes individual requests. This is normally a difficult service to manage, but WebSnap handles all the details, and makes the session information available both in server-side script and the web application extension code. Login Services Web applications need security to be implemented, requiring users to log in to the given application. WebSnap automates this process by providing a specialized login object. This component contains the functions needed to properly query and authenticate users according to the application s chosen security model. It gathers login information, and in conjunction with WebSnap session management, provides current login credentials for each request. The login components also automate login validation and login expiration. Throughout the application, users who try to access unauthorized pages can be automatically referred to the login page. Tasks that previously required custom coding for each web site are now easily integrated into any web application with the addition of a single component. User Management Services Working with the login services are user management services. WebSnap includes components to manage lists of users and user information. These classes provide information about the users logged in to an application, and assist in maintaining the user s session. As with all WebSnap objects, the user management components are used in server-side scripting to provide user information such as name, color preferences, etc. These classes make customizing a web site to a user s preferences simple and straightforward. File Uploading Services Managing the uploading of files from a client is a very difficult task for most web development tools not so with WebSnap. WebSnap provides a simple solution that manages the multi-part forms needed to upload files. Developers can provide file upload capability in a WebSnap application with a fraction of the effort of other development platforms. 6 Access Rights WebSnap includes built in application services to handle access rights. Access rights can easily be assigned to individual users, and WebSnap developers can manage those rights as desired, whether via a proprietary solution, or in conjunction with the operating systems access rights system. WebSnap includes extendable components to make handling a user s permissions seamless and easy. File Management Services Another key function of a web application is managing files, whether they are HTML files for display or other files to be downloaded or viewed by users. Managing these files can be difficult because URL paths and file system paths are not synchronized. Finding the files relative to a web server s host directory can often be troublesome. WebSnap provides file management services that allow for tracking and location of files needed within a web application. For instance, HTML template files produced by an HTML coder or a web site design tool can be stored for use in a WebSnap application, which loads pages as needed to provide a proper face. Server-side Scripting A key part of WebSnap is its server-side scripting capabilities. Out of the box, WebSnap supports JavaScript, VBScript, or any ActiveScript engine. Server-side scripting in WebSnap is the link between the Delphi developer s application and the structure of the web site. The script accesses WebSnap objects in a WebSnap application in order to display dynamic content. Script managed this way is extremely secure it cannot improperly alter the state of the WebSnap application or corrupt data internal to the application. WebSnap enables developers to run and debug their applications locally. The WebSnap debugging features promote robust applications, enhancing the quality of a company s web site. Debugging and testing web applications are two of the more difficult challenges facing web development teams. Setting up test web servers on

7 local machines and using them to test code is a slow and arduous process. Tools for debugging applications are frequently not very full-featured, if such tools exist at all. WebSnap provides a testing and debugging platform that makes the process simple and informative. The debugging platform in WebSnap gives web teams access to the power of a true debugger, greatly reducing development time and enhancing the quality of the finished projects. The WebSnap debug server also tracks all communication back and forth between the browser and the application something no other system can do. Web Snap and other Web application technologies WebSnap Cold Fusion ASP CGI Native Code Open Standards Web Service Integration Broad Database (ODBC) (ADO) Connectivity EJB Integration CORBA Connectivity Integrated Debugging Capabilities Deploy to Multiple Web Servers High Scalability WebSnap integrates the entire IT investment within its application design environment it brings the entire business to the Web. WebSnap applications can access all of a company s data, any COM or CORBA object on a network, or aggregate functionality from Web Services into the web site s application. WebSnap frees the development team to choose the specific technology or way of building a web site that works best for them and their company, avoiding lockdown into vendorspecific solutions. WebSnap integrates with existing web site design tools taking advantage of existing skill sets and gives a team the power of a ultra-high performance web server extension. With a fully extensible, object-oriented framework, WebSnap enables teams to customize solutions tailored specifically to the business. Scalability is guaranteed a WebSnap solution is as scalable as the web server on which it is deployed. WebSnap will also be ready to carry web development into the future. Using BizSnap e-business features, WebSnap is ready to adapt to any Web Service platform that may be introduced to the company, whether it be Microsoft s.net, Sun Microsystem s ONE, or others. WebSnap protects development teams against changes in the industry effectively futureproofing applications. Compare WebSnap with other web application solutions: Active Server Pages (ASP) / InterDev / Macromedia UltraDev ASP is a scripting-based technology provided by Microsoft. There are various tools available to aid in the development of ASP applications. ASP scripts are embedded in HTML. When the ASP request comes in, the request is passed to the ASP library, interpreted, and HTML is returned to the browser. ASP can take advantage of COM objects for data access and other dynamic content, but frequently much of the data handling and logic of the web application can end up in the script. This can often result in the script having more control over the internal workings of the business logic than application designers might like. ASP lacks access to Web Services, effectively limiting its ability to automate a company s supply chain. It also does not possess CORBA connectivity, which forces recoding and duplication of business logic already present in a company s enterprise systems. 7

8 With a restrictive data access architecture, it limits its potential connectivity to a company s IT infrastructure. Finally, its limitation to an IIS platform introduces security and scalability issues that may not be present on the Netscape or Apache platforms that WebSnap supports. WebSnap provides the advantages of ASP while avoiding the pitfalls mentioned, with the added robustness of the technology embedded in WebSnap objects and PageProducers. By limiting server-side scripting to only the presentation of content with WebSnap objects, it ensures that HTML files only deal with content presentation and not business logic. This ensures that HTML coders never have to worry about content in their HTML pages that doesn t present information to the user. Cold Fusion Cold Fusion is another competing web application development technology that relies on scripting, in this case in the form of embedded HTML-like tags in an HTML page s code. Cold Fusion provides an interpreter library that reads the tags and replaces them with the appropriate HTML for display to the end user. Cold Fusion is dependent on this interpreter to execute all of the business logic and content management of a web site, and as a result, it does not scale well. Large web sites will require multiple, clustered servers to execute all the Cold Fusion code that is presented to many client requests. Cold Fusion suffers from the same limitations as ASP, in that much of the business logic of an application must be embedded in the HTML pages that a user will see. This again makes managing that HTML between various team members more difficult, and increases the risk that errors in the HTML code can alter or destroy data. It also shares ASP s lack of Web Services, and its limitation to ODBC or OLEDB data access, restricting its implementation as a true enterprise web development environment. WebSnap, of course, does not suffer from these limitations, as its server-side scripting is only concerned with content display, and leaves all the business logic in the native web server extensions where it belongs. PERL Scripting/CGI PERL and CGI (Common Gateway Interface) executables were the original solution for dynamic content on the web. PERL is ubiquitous and widely used. Most servers support PERL/CGI. However, using it as a development platform limits the development team to primitive CGI technology (in many cases requiring hand-coding around difficult APIs), and provides only limited access to corporate data and other means of encapsulating business logic. Summary WebSnap brings Delphi into today s web development teams seamlessly, dovetailing easily with existing scripting, layout, and graphical technologies. Delphi reduces maintenance costs and speeds development time with broad-ranging interoperability features and transparent web server API layers, enabling teams to reuse existing IT infrastructure for new development. Web development teams using WebSnap are highly productive, and can bring all the back-end processes of the business to the web site, whether those processes originate as Web Services, CORBA objects, EJBs, or a wide variety of RDBMS servers. Scenario In a sample case, a hypothetical airline company, Overhead Airlines, wishes to automate some of its service processes. This company has business partners to whom it looks for fuel, ticketing, and other portions of its business. Each of these elements might pass through a web application to have input into the company s central data storage. Overhead s existing web team is highly skilled with DreamWeaver or UltraDev and Overhead chooses Delphi 6 as the business object platform. 8

9 The airline may wish to reduce its overhead in fuel storage and transport costs. Arming its maintenance managers with wireless browsers, these managers access a WebSnap application tracking the status of individual aircraft as they arrive at the terminals. The maintenance crew reports to the central IT system the need for certain quantities of fuel. The WebSnap application links to a fuel cost report via a Web Service, establishes the most economical price for the plane, and links to a second Web Service at the fuel supplier chosen to order fuel for immediate delivery. Moments later, the truck is dispatched and the plane is refueled. Maintenance staff are updated immediately, and the airline headquarters can view the status of its aircraft at a moment s notice. application, because Delphi 6 provides access to their disparate data as if it were all in one place. With WebSnap, Overhead Airlines is able to display data from various servers and locations as if it were all in one place. Users and customers can update records without concerning themselves with the source of the information. In addition, much of the functionality needed for the web application already exists in the form of CORBA objects and applications on Overhead s application server. WebSnap allows the application to easily access and thus leverage this existing functionality, transparently integrating the web application with the functionality of existing client/server applications. The airline may also have certain rules for offering ticketing discounts. These are published on a J2EE application server such as Borland AppServer, in its headquarters. A WebSnap application offered to ticketing agents might harness these rules using CORBA, and automatically update a customers billing resulting in higher customer satisfaction, more efficiency to the discount programs, and return business. As the rules are changed to reflect different promotions, the AppServer is updated with the new values, and the WebSnap application around the world reflects this immediately. As this WebSnap application is built, developers realize that some of the data that they need to access is on an Oracle 8i server, and other data resides on Microsoft SQL Server. Using dbexpress and DataSnap, the developers mesh this data together seamlessly into the WebSnap application. The handling of data from different sources does not stand in the way of building the Access to the application itself is limited only to authorized users. Admission to various parts of the application is restricted to appropriate users using the WebSnap built in session and user control. Views of the data are easily customized on a per-user basis. All of these features are managed and coded with minimal effort using WebSnap built in functionality. As the application grows and expands, the developers have no difficulty scaling it, as the WebSnap architecture scales right along with the web server. Data access is never a bottleneck with dbexpress, DataSnap, and BizSnap. The development platform never limits the developers to specific technologies. WebSnap puts the team on track to integrate the entire enterprise quickly and cost-effectively. 9

10 Conclusion Delphi 6 and WebSnap provide a next-generation scalable and customizable web application development platform that integrates all of a company s IT infrastructure. By providing the latest technologies, standards-based outputs, and a rapid application development environment, WebSnap has all the power a company needs to build the cutting edge web sites of today and tomorrow. WebSnap applications easily bring together the power of server side scripting, CORBA, EJBs, enterpriselevel database access, and web service publishing and access. WebSnap binds together all of these capabilities to create a web object foundry that easily integrates into today s web application development team. Managers choosing a powerful, enterpriselevel web application development tool will find the solution in Delphi 6 and WebSnap. 100 Enterprise Way Scotts Valley, CA Made in Borland Copyright 2001 Borland Software Corporation. All rights reserved. All Borland brand and product names are trademarks or registered trademarks of Borland Software Corporation in the United States and other countries. Java is a trademark or registered trademark of Sun Microsystems, Inc. in the U.S. and other countries. CORBA is a trademark or registered trademark of Object Management Group, Inc. in the U.S. and other countries