Documentation - Add interface for AbrController (#4842)

* create an interface for abr controllers

* use AbrComponentApi interface in abr-controller.ts

* update docs for custom abr controllers

* remove clearTimer from abr interface and documentation

docs/API.md

@@ -908,10 +908,9 @@ var config = {
 
 Customized Adaptive Bitrate Streaming Controller.
 
-Parameter should be a class providing 2 getters, 2 setters and a `destroy()` method:
+Parameter should be a class providing a getter/setter and a `destroy()` method:
 
 - get/set `nextAutoLevel`: return next auto-quality level/force next auto-quality level that should be returned (currently used for emergency switch down)
-- get/set `autoLevelCapping`: capping/max level value that could be used by ABR Controller
 - `destroy()`: should clean-up all used resources
 
 For `hls.bandwidthEstimate()` to return an estimate from your custom controller, it will also need to satisfy `abrController.bwEstimator.getEstimate()`.

src/controller/abr-controller.ts

@@ -14,9 +14,9 @@ import type {
   ErrorData,
   LevelLoadedData,
 } from '../types/events';
-import type { ComponentAPI } from '../types/component-api';
+import type { AbrComponentAPI } from '../types/component-api';
 
-class AbrController implements ComponentAPI {
+class AbrController implements AbrComponentAPI {
   protected hls: Hls;
   private lastLoadedFragLevel: number = 0;
   private _nextAutoLevel: number = -1;

src/types/component-api.ts

@@ -1,7 +1,14 @@
+import EwmaBandWidthEstimator from '../utils/ewma-bandwidth-estimator';
+
 export interface ComponentAPI {
   destroy(): void;
 }
 
+export interface AbrComponentAPI extends ComponentAPI {
+  nextAutoLevel: Number;
+  readonly bwEstimator?: EwmaBandWidthEstimator;
+}
+
 export interface NetworkComponentAPI extends ComponentAPI {
   startLoad(startPosition: number): void;
   stopLoad(): void;