Is it possible to develop application based on Confluence platform?

Hi all,

We want to develop a Portal application based on Confluence (so that our company internal users can interact with both Confluence and this application in a single page view of browser) with below features:

- the application has 5+ screens in which user can read / write data. Thus we need to define our own database tables

- the application reads data from LDAP

- the application wants to aggregate the list of Confluence pages / blogs that a user has subscribed

Questions:

- is it a good idea to implement the application in Confluence? Why and why not?

- if yes, then could you give me some guideline / documentation / sample codes for that? (I saw some sample codes for Confluence Macro, but it's simple for an application need)

Additional notes: 

- another direction of this problem is to build the application from scratch and use iframe to include that application into the Confluence. But it's not cost-effective to build from scratch and I heard that integration between application and Confluence also costs a lot.

- I did Google to find some guidelines, but it seems not valid to my need

• https://developer.atlassian.com/docs/getting-started/learn-the-development-platform-by-example/store-and-retrieve-plugin-data

• https://developer.atlassian.com/confdev/confluence-server-rest-api/confluence-rest-api-examples

• https://developer.atlassian.com/confdev/confluence-plugin-guide