In my company we develop internal products and usually this products must be integrated (typical scenario). Our solution is always use SOA web services for this kind of task.
This is a solution that forces different products to develop same UI interfaces, and the responsibility of this interfaces or process is sometimes not clear between our teams.
I want to propose an alternative solution, I think that sometimes each product publish SOA web services but in addition publish web-pages, that other products can call to reuse.
for propose it in the work, I want document my-self because I suppose that this kind of integration is already invented, and have a name, examples, tools, best-practices...
any orientation?
To me it looks like a mistake to share entire UIs across applications. This will violate the separation of concerns principle, and will couple applications to each other. Also, you will end up losing autonomy because an external application will control how your UI looks. You will have all kinds of issues, related to the inter-dependencies between applications. These are the first that come to mind:
- I assume the information is not public. If so, you'll need single sign-on between applications. In order to implement some level of security (at the very least authentication) you'll need to integrate all your applications within a single sign on-solution or invent some kind of convention for passing tokens between applications.
- It will be very hard to implement even primitive authorization if needed, because naturally roles in different systems vary, especially across business domains.
- If you have to filter any data by some property, it will have to be transferred in the request to the central application that holds the GUI prior to displaying. The whole processing of data and preparation for visualization will then be responsibility of this central UI system. This will lead to insane amount of caller-specific rules for each caller that uses the central UI.
- Any complex UI required by applications will still have to be implemented locally, so you only solve the issue partially.
Here is what I would do in your case if I really must implement central UI, although I advice strongly against it and would prefer sticking to SOA with some kind of middle ware (ESB or even more primitive EAI software that limits point-to-point integration). You can decide for yourself if it is worth the time and effort:
I would only offer a very limited version of UI that is 100% based on the service layer that already exists and is generated automatically. This means - if you change the service the UI accommodates the new data and displays it automatically. If an application needs complex visualization it must still use the Service layer to retrieve data and implement custom UI locally. In genera, it will be better if UI and visualization are controlled by each application separately. This is much more agile and future-proof.
Hope this helps!