What is XML
For some time we have started to coexist with a new acronym in the technological world: XML (Extensible Markup Language) or Extensible Markup Language. But what does this name not so significant to our ears consist of? Below I will show the competitive advantages of using this technology in business applications.
XML in my application?
XML or Extensible Markup Language, is a language of Tags or labels that allows to define in a very simple way the hierarchical structure to which a data belongs, as well as HTML allows to define the way in which a data is displayed in our browser
Until now, the most important deficit when integrating applications developed in different languages or on different platforms, was that each way of transmitting data was the owner of the application that generated it, and in many cases the way of transmission did not allow the communication was smooth. This problem occurs even when trying to integrate applications on the same platform developed in the same language. In the best case, once data communication was established, we ran into a real problem when structuring it hierarchically according to the source model.
XML allows, in a very simple way, to structure the information in order to send it with total assurance that the receiver will know that this data has a relationship with other data within the same structure sent, it can also know what type of data is what you are receiving (XML Schema), you can set how to display it (XSL) and even how you have to return it (SOAP)
Thus XML allows communication from one application to another, or receive and send structured data through the Internet without having to devise complex or excessively heavy mechanisms to rearm the information as it originally was.
XML has multiple uses. The data transmission is its origin, but integrated with XML Schema you can define the type of data that is traveling, or if null, repeated, decimal values are allowed or if it is a data that maintains a referential integrity with other information in the same document transmitted.
XML is the source of SOAP, a protocol based on the standard that allows the sending of two-way information packets for the integration of remote applications. Thus being able to transmit data by reference and even in a transaction.
XML with XSL allows information to be visually modeled for presentation to generate dynamic presentations mainly oriented to B2C
XML is a way to parameterize applications in a simple, readable and understandable way for both applications and people and easily accessible from any type of application
99% of current desktop applications support reading, writing, importing, and exporting to this format to persist information consistently, and with each new XML version it becomes more integrated into the Back Office of desktop, management, and Web systems, etc.
All this with a descriptive model in text format, and based on industry standards defined by the W3C (World Wide Web Consortium), which guarantees that the information can be transmitted over the Internet without any kind of obstacle (Firewalls) and that the Interpretation of it is universal beyond development platforms or languages.
A solution today should not close the possibility of integration or communication with new applications, modules, functionality or devices. Taking into account the transmission and integration of information using XML is a necessary requirement when establishing the scope of a solution.
For all this, a technological solution is not such if the use of the XML infrastructure in it has not been properly analyzed.
The analysis, fundamental
Like any other tool, architecture, methodology, etc. related to projects, not only computer, but of any kind, the initial and essential element is the detection of a need at a certain time and the subsequent analysis of it.
In this analysis, where the needs that give rise to the solution are defined, the immediate and future possibilities of using XML must be measured. But its use can vary drastically depending on the scenario in which you want to implement the solution.
Below are some practical examples that we find in the projects we develop at Improven Consultores and that clearly show the real possibilities of XML in the integration of management applications in the company.
Heterogeneous information systems
A classic and very important example is the use of XML in the integration of heterogeneous information systems.
Currently, the market is flooded with specific and / or vertical applications, which together with the existence of general and / or horizontal applications, means that applications developed on platforms, data models and different languages must often be integrated.
Thus, we usually find three options when this type of problem arises:
- Keep applications working properly and integrate with XML. Change all systems to achieve "factory" integration. Do not integrate while keeping applications independent.
It is logical that the decision made should be technologically and cost-benefit based.
The third option, that is, the existence of non-integrated applications is very problematic due to the inefficiencies that are generated in the company's processes, so this option should be discarded, although it is actually found more times than would be advisable..
The second option, that is, changing all systems has a very important impact in terms of costs and in terms of changes in companies, which is why it is also often dismissed.
Compared to the other two options, the use of XML allows the development of an integrating solution (MiddleWare) so that the systems that are tested and working correctly can communicate with each other, giving the advantage of achieving the best integration, with a contained cost and with the advantages of achieving short-term results.
In this sense, the architecture that would be presented in the integration of the systems is as follows:
Example: Catalog management on the Internet
XML also offers important opportunities for managing electronic catalogs over the Internet.
Compared to other languages, the use of XML allows content management to be limited to loading it into the database and it is not necessary to do each page of the catalog by hand.
Catalogs must be managed with the use of XML as a means of transporting the data of articles, families, categories, descriptions, etc., and the formats of their display will be given by XSL and its XPath language, which dynamically allows the content to be put together from a catalog.
In this way, we find different scenarios:
Scenario with a data source and several possible presentations (different presentation templates depending on certain parameters):
This concept allows to give a different visual format to the data poured by an XML with a certain structure, so that the data can be displayed under different templates. The power of this concept allows managing multiple electronic stores from a single data source.
Scenario with several data sources and a presentation model (catalog concept):
In this case the data structure received in XML is combined with the template in XSL resulting in a similar display for all the data received in that structure. The electronic catalog is the quintessential case where all products with their descriptions and characteristics are always displayed in the same format.
Mobile devices
Nowadays the mobility of the personnel of a company is in many cases vital for its operation. The main complication in these scenarios usually consists of providing the user of the mobile device with Immediate, Timely and Updated information from the data center.
In addition, the user must have the possibility to modify said information and update it in the data center without having to physically move, connect to the network and update.
Mobile technology currently allows us to use PDAs, Laptops, mobile phones, etc. that it can communicate with a server exchanging information with XML, WML and Web Services, and thus optimize the dynamics of the company with reliable and updated information at all times.
Web Services
Perhaps the technology that will give the most to talk about in the immediate future is that related to Web Services. This new form of data transmission allows bidirectional communication, with which you can establish communications between applications using standard XML-based protocols such as SOAP (Simple Object Access Protocol), and specifications (although not standard yet) such as UDDI (Universal Description, Discovery and Integration) and WSDL (Web Service Definition Language).
These technologies encapsulate XML in transmission packets or messages (SOAP), allow the location of existing Web Services on the Internet as if they were Web Services Yellow Pages (UDDI), and give the possibility that the application that makes Use of the Web Service includes the latter's communication interfaces (WSDL).
These set of definitions allow distributed applications to be based on open standards-based technology as opposed to proprietary protocols like DCOM or CORBA.
The result is the possibility for desktop or web applications to communicate with other remote applications to obtain or manage data, as if it were a local application, regardless of the platform on which each one is, as long as the aforementioned standards are respected..
Thus, if our application requires the current quotation of a certain Company, a Web Service that provides this information can be searched using UDDI, use its programmatic interfaces with WSDL, and finally communicate our application with the Web Service through SOAP, without the need of having to worry about firewalls that could interrupt communication because it is a standard based on plain text and that communicates by a protocol mounted on
Fashion or Solution
Perhaps the fact of hearing so much about XML, XSL, SOAP, Web Services, can lead us to the erroneous conclusion that it is nothing more than a simple fashion due to the lack of technological results in recent times.
The truth is that XML is a technology that promises to stay with us for a long time.
As we said in the previous installment, the main software companies worldwide have bet all their chips on the integration of systems and devices. The short - medium term objective is that the applications serve data that can be viewed interchangeably on Web pages, Mobile Phones, PDAs, Laptops, Television, Home Appliances, etc. And the only possible form of integration so far is data transmission by XML and communication by SOAP (Web Services).
A study carried out by the Giga Group shows that in 2002 XML was used in 45% of the so-called critical applications, which gives a clear idea of the weight of this technology in the development of current applications.
conclusion
XML is a tool that must be taken into account when establishing technological solutions. The scenarios presented in this article are just some of the infinite possibilities that this language presents.
XML is not the ideal solution in all cases either because it has its bottleneck in execution performance and because bandwidth costs are not ideal for the use of this technology, although they become more accessible day by day..
Also the leading technology companies such as Sun, Microsoft, IBM, etc. they support XML in all the lines of software products and have their own frameworks for the development of XML Web Services.
The future trend is clearly marked.
