什么是SOA中的“包装服务”？

Question

I have looked on the web but I am confused as to whether a wrapper service wraps a legacy application, or a set of complex services.

Update: Judging by the answers I have received there is no accepted definition for a "wrapper service" in SOA, and after further investigation I realised that "wrapper services" depends on who defines it. I mean in an Oracle context.

Answer 1

All - part of the confusion around this term stems from simply being mis-spoken...

It's NOT "wrapper SERVICE", but rather "service WRAPPER" :-)

Once you get the TERM itself correct, things start to make sense: - a "wrapper SERVICE" sounds like a SERVICE which creates "wrappers" - WRONG; - a "service WRAPPER" sounds like code which encapsulates or "wraps" an existing body of code, and gives it the ability to act as a SERVICE - RIGHT !

It's now obvious we're talking about SERVICE WRAPPERS here, and now it starts to become clear(er) that it DOESN'T EVEN MATTER what sort of code is encapsulated "inside" the wrapper, because the wrapper code acts like a FUNCTION, where there is a "interface" (established input formats & output formats) that is all the users interact with, making the guts inside a "black box" the user NEVER needs to know about...

This wrapper then presents to the user as something like a FUNCTION; the user submits inputs to the "service"... and gets back outputs. The wrapper itself then has code which internally interacts with the legacy or new code inside the wrapper, formulates an output, and returns this output to the requester (user) :-) ...

Historically service wrappers were the favorite way to re-purpose legacy code which did NOT all by itself behave like services (background-running programs capable of listening & responding to requests, aka daemon processes), but as organizations worked to evolved toward SOA, this was a great way to quickly turn legacy "apps" - typically NOT running in background - into services.

Hope this helps. -MV markvogt.vogtland.ws

Answer 2

我将包装器服务理解为包装某些东西的服务，无论是另一种服务，一组服务还是遗留应用程序。

Answer 3

"wrapper service" which is also more widely known as "legacy wrapper" is used to wrap a legacy component to prevent coupling issues in soa.

hiding complex systems or a set of services is done using the "facade service"

Answer 4

Arguably the entire point about SOA is that everything is a wrapper. That is , a web service is just a facade, and there is no way to tell whether it fronts a "legacy application" or "a set of complex services".

Answer 5

包装器服务是一个或多个Web服务的组合，其封装了不同模块的逻辑，由此单个模块能够以最小的集成问题与其他模块通信。