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docs/Automated Controller Loading with Child Controllers.md

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+# Automated Controller Loading with Child Controllers
+While loading controllers automatically from a provided directory is an overall helpful feature in abbreviating the code for the end developer/user while maintaining a high level of flexibility. However, it does introduce a particular problem with child controllers.
+
+## The Issue
+The issue with a naive approach of just calling `setup` on all controllers we find in the designated directory (and it's subdirectories) is this would produce duplicate callbacks for the same route. This is because we would both call `setup` as we find the controllers but ALSO inside the `Controller` decorator for child controllers.
+
+## The Solution Impact
+However, to resolve this has meant multiple entire passes of all the found controllers which if there is a large amount of controllers could be pretty inefficient in a number of ways. 
+
+For instance, this means that parallelization of loading is limited to the initial loading rather than calling of `setup`
+
+Another way, our particular solution to this issue, at least currently, precludes using any kind of greedy methodology which if we could use could make the loading significantly more efficient. 
+
+This is because we can't know that the parent controller (with the `ChildController` decorator) would be processed before any child controller is.
+
+## The Solution
+The following is the isolated code that addresses this particular issue
+
+```typescript
+// Get all controllers that have the child controller decorator
+const controllersWithChildControllers = loadedControllers.filter(controller => Reflect.getMetadata('ChildController', controller) !== undefined);
+
+// Get all those controllers that are designated as children controllers by parent controller
+const childrenControllers = controllersWithChildControllers.map(controller => Reflect.getMetadata('ChildController', controller));
+
+// Get the exclusive set of controllers that don't fit in the group of controllers with child controllers OR a child controller themselves
+const controllersWithoutChildren = loadedControllers.filter(controller => !controllersWithChildControllers.includes(controller) && !childrenControllers.includes(controller));
+
+// Take the list of controllers with child controllers and the list without children (that excludes children themselves)
+// And forma a list that has all child controllers removed
+const topLevelControllers = [...controllersWithChildControllers, ...controllersWithoutChildren];
+```