[Technical Review Series]-understand the full picture of WebService

Why do we need to use WebService?

1: The biggest advantage of WebService is to achieve interoperability between heterogeneous platforms.
This is also one of the main reasons for using WebService. In this way, any two applications can communicate with each other as long as they can read and write XML.
2: More extensive software reuse.
We can use any language to package a set of functions into WebService under any platform, and then register it with UDDI. As long as you get the WSDL file describing WebService, you can use the proxy tool to automatically generate a suitable client proxy, and then you can access the functions provided by WebService through the proxy.
3: more powerful communication capabilities
WebService can use XML-based SOAP to represent data and call requests, and transmit data in the XML format through the HTTP protocol, because the call request and response message can pass through the firewall at this time, generally, only port 80 is open. Data shows that some of the so-called distributed component technologies implemented before WebService are represented in binary format and need to communicate through special ports. It is obvious that a firewall will fail.

What scenarios is WebService suitable?

1: Application in the e-commerce industry such as packaging some general logic for other companies to use.
2: Application Integration (which has a sacred role for large enterprises to implement SOA)

What major protocols are used in WebService?

SOAP: XML-based protocol, which is simpler than DCOM and CORBA.
The following describes the entire WebService call process:
The client sends a request to the WebService method. At this time, the client serializes the parameters that call the WebService Method to the server. After deserialization, the client restores the parameters obtained from the client and passes them to the WebService Method for calling, after the call is completed, if a return value exists, the returned value is serialized again and then sent to the client. Then, the real return value is obtained through deserialization. The call ends. In this process, we can do a lot of things, such as scaling up SOAP and improving the security of WebService.
WSDL: a document describing WebService
UDDI: a place for publishing WebService
DISCO: Discovery of web WebService is similar to UDDI.

Where does WebService work?

It should be unrestricted. It can be used as long as SOAP messages can be identified. This is no longer a problem today with XML as the standard.
1: The Browser executes WebService. For example, to execute WebService through a HTTP-GET or HTTP-POST, but this method is cumbersome, generally not considered to use.
2: Application in. NET development, the simplest, all automated.
3: The application is not. . NET environment. For example, some tools provide client tools for accessing WebService.

To be continued...