1. What is SOA
Service-Oriented Architecture (Service-Oriented Architecture, SOA) is a component model.
2. Why use SOA
The traditional architecture, the package is being prepared for independent (self-contained) software, that together in a complete package will feature a number of applications. Code to achieve the integration of application functionality and function code itself is usually mixed together. We called the software design in this way. "
A single application. "Closely related to this is that part of the code will change the code to use the code has a significant impact, which will result in system complexity and increase the cost of maintaining the system. But also enables re-use the application functions become a little bit more difficult, because these features are not intended to be reused
The play package.
Disadvantages: redundant code can not reuse the high cost of tight coupling.
SOA intended single application functionally separated from each other, so that these functions may be used alone as a single application functionality or "components." These components can be used to create a variety of other in-house applications, or if necessary, publicly available to partners for use in partner applications
program.
The advantages of SOA: loosely coupled code reuse platform independent language independent.
3, SOA works
SOA architecture has three roles:
Service Provider: publish their services, and to respond to service requests.
Service registry: Registration has released the web service, classify, and provide search services.
Service requester: Using Service Center to find the services they need, and then use the service.
SOA of three operations:
Publish action: In order to make the service accessible to the need to publish service descriptions service users can find it.
Find operation: service requester location-based services by querying a service registry to find meet their standards of service.
Bind operation: After retrieving the service description, service users continue to call the service based on the information in the service description.
SOA-related standards --WSDL, UUDI, SOAP
SOAP: Simple Object Access Protocol (Simple Object Access Protocol)
WSDL: Web Services Description Language WSDL (Web Services Description Language)
UUDI: Universal Description, Discovery and Integration (Universal Description, Discovery and Integration) WSDL is used to describe the service;
UDDI to register and lookup services;
SOAP, as the transport layer for transmitting messages between the service provider and the consumer. Consumers can find a service in the UDDI registry (registry), access to services WSDL description, then call the service via SOAP.
SOA system - three core components:
1, ESB (Enterprise Service Bus) Enterprise Service Bus ESB is a product of technology combined with traditional middleware technology and XML, Web services. ESB provides the most basic network connection hub is an essential element to build enterprise nervous system.
From a functional point of view, ESB provides event-driven and document-oriented processing mode, and distributed operation and management mechanism, which supports content-based routing and filtering, with a transmission capacity of complex data, and can provide a range of standard interfaces .
ESB's five basic functions:
1) MetaData management services: registered name within the scope of bus services and addressing management functions.
2) Transfer Service: You must ensure that the correct message by bus interconnect between the enterprise business process delivery, transmission also includes content-based routing.
3) Medium: Routing services, and location services to provide location transparency; various forms of messaging; supports transmission protocol widely used.
4) a variety of services in an integrated manner: such as JCA, Web Services, Messaging, Adaptor and so on.
5) management support services and events: such as service call records, measurement and monitoring data; provide event detection, triggering and distribution functions;
2, BPM (Business Process Management) Business Process Management so-called business process management is based on changes in the business environment, promote the integration between people, people with adjusted operating systems and methods of IT tools and solutions.
BPM can make the system more robust by BPM components, SOA can better monitor the system it is connected.
3, Portal Portal Portal is a WEB-based application that provides a personalized, single sign-on, content aggregation from different sources and storage of information systems presentation layer. Portal is an integrated low-cost technology. If companies already have a lot of faith
Information systems, Portal can easily integrate these systems together, and in a uniform manner to the user interface.
4, building an SOA
A SOA system must have the following six key elements - infrastructure, existing resources, corporate services, process models, services and systems to show the tools (including development, testing and management tools, etc.).
On the basis of the existing infrastructure and resources are in place on the development and build a SOA system to include the following aspects: First need a standard design and development services, which is the core element of the overall SOA system. Standards-based service
Business, with process orchestration and modeling tools, organizational structure of the process, generating process models to better meet business needs. The actual building and the development of SOA systems, including the development of services and applications, data access, processing and management,
And so on to show various forms of services.
5, SOA applications