Web App Proxy migration to APIGEE

[apxsharma]

We have a legacy "Web application" that uses traditional J2EE MVC architecture. The web application is like a thin proxy that does request validation and transformation, calls back-end services, and finally transform the response payload before returning it to the caller. Since this application does everything that a Proxy does, we are planning to move this application to the APIGEE. Since most of my web app code is written in Java, I am planning to use Java callout to perform everything that is being done in my existing "Web App". What I wanted to know is - Are there any other way to migrate the "Web App" logic in the APIGEE? Any experiences you can share?Any prior post you can refer me to?

[dchiesa1]

Yes, I have some experience to share.

I would advise against doing everything in Java code, in a custom callout.

You can certainly do that; it will work. but it's probably not the best way to do things in Apigee.

• for calling backend services, use the Apigee target. It's designed for this purpose and it exploits asynchonous I/O. The vast majority of Apigee customers use this. doing the upstream connection on your own in Java code you write, is probably not the best way.
• for request validation, use the built-in policies like MessageValidation or ExtractVariables.
• For transformation, use XSLT or JS. or a combination.

There is no automated way to transform a J2EE MVC app into an Apigee proxy. You'll have to re-implement it. Fortunately, it's usually not too difficult in Apigee.