> For the complete documentation index, see [llms.txt](https://docs.mernkit.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mernkit.com/back-end/application-structure.md).

# Application Structure

Below I will list the general API layout. I will not list all functions just a few to give you an understanding of what you will find in each file. 

* App.js (Entry Point) 
* nodemon.json (environmental variables used for debugging)
  * Controllers
    * stripe-controller.js (Stripe middleware functions) 
      * Get Plan Options  
      * Get Subscription Status... 
    * users-controller.js (User  middleware functions) 
      * Get Users
      * Get Permissions...
  * Middleware
    * passport.js 
      * Facebook Authentication Strategy
      * Google Authentication Strategy 
      * JWT Authentication Strategy... 
  * Models
    * http-error.js 
      * Wrapper for error responses. 
    * tenant.js
      * Mongoose Model for Tenants
    * users.js
      * Mongoose Model for Users
  * Routes
    * stripe-routes.js
      * routes to controller methods starting with /api/stripe
    * users-routes.js
      * routes to controller methods starting with /api/users
  * Shared
    * email.js
      * wrapper methods for mailgun transactional emails
    * helper.js
      * method to handle potential tenant name collisions
    * stripe.js
      * wrapper methods for strip operations
        * Cancel Subscription
        * Update Subscription...


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