SOA Architecture

SOA framework

         Just to understand SOA, Let's look at two scenarios ：
         Suppose a user performs an order placing operation , The processing logic of the system is to check the inventory of goods first ,
         Orders can only be submitted if the inventory of goods is sufficient , So the logic of checking inventory ,
         Is it placed in the order subsystem or the inventory subsystem ？ There must be very in the whole system 
         Many similar scenarios of shared services , These business logic scenarios must be created repeatedly ,
         This produces a lot of redundant business code , The maintenance cost of these redundant business codes will increase with 
         Time is getting higher and higher , Can you pull out these shared business logic , Form reusable services 
         Well ？
         There are many subsidiaries under a group company , Each subsidiary has its own business model and information 
         precipitation , There is no interaction and sharing between subsidiaries . At this time, although the subsidiaries can 
         Create some value , However, because the information between subsidiaries is not interconnected , each other 
         An island of information is formed between them , Make it impossible to maximize value 

Based on these problems, we introduce SOA（Service-Oriented-Architecture）, That is, a service-oriented framework

	   Semantically speaking , It is similar to process oriented 、 object-oriented 、 The idea of component orientation is the same ,
	   Both are software components and development methods . The core goal is to put some common 、 There will be more than one 
	   The shared services invoked by the upper layer services are extracted into independent basic services , These are extracted 
	   Shared services are relatively independent , And can reuse , So in SOA in , Service is the core 
	   Abstract means of , Business is divided into some coarse-grained business services and business processes .

As shown in the figure ： Extracted , Customer service , Inventory service , Multiple shared services such as goods and services . stay SOA Will use ESB（ Enterprise service bus ） As a communication bridge between systems and services .ESB It also provides the management of service address 、 Protocol conversion and data format conversion between different systems , The caller does not need to care about the location of the target service , This makes the services dynamic , The advantage of this is to achieve a high degree of decoupling between the caller of the service and the provider of the service . in general ：SOA The main problem to be solved is ：

• Information Island
• Reuse of shared services