refactor: add Configuration type (temp aliased to IConfiguration)

Author: rasendubi

src/configuration-store/configuration-store.ts

@@ -1,4 +1,4 @@
-import { IConfiguration } from '../i-configuration';
+import { Configuration } from '../i-configuration';
 import { Environment } from '../interfaces';
 
 /**
@@ -9,17 +9,16 @@ import { Environment } from '../interfaces';
  */
 export class ConfigurationStore {
   private readonly listeners: Array<
-    (configuration: IConfiguration | null) => void
+    (configuration: Configuration | null) => void
   > = [];
 
-  // TODO: replace IConfiguration with a concrete `Configuration` type.
-  public constructor(private configuration: IConfiguration | null = null) {}
+  public constructor(private configuration: Configuration | null = null) {}
 
-  public getConfiguration(): IConfiguration | null {
+  public getConfiguration(): Configuration | null {
     return this.configuration;
   }
 
-  public setConfiguration(configuration: IConfiguration | null): void {
+  public setConfiguration(configuration: Configuration | null): void {
     this.configuration = configuration;
     this.notifyListeners();
   }
@@ -31,7 +30,7 @@ export class ConfigurationStore {
    * Returns a function to unsubscribe from future updates.
    */
   public onConfigurationChange(
-    listener: (configuration: IConfiguration | null) => void
+    listener: (configuration: Configuration | null) => void
   ): () => void {
     this.listeners.push(listener);
 

src/i-configuration.ts

@@ -28,6 +28,12 @@ export interface IConfiguration {
   isInitialized(): boolean;
 }
 
+// TODO: replace more abstract `IConfiguration` with some concrete
+// implementation, so we know what to expect from it (i.e., it's
+// probably a bad idea to allow users implementing their own
+// configurations).
+export type Configuration = IConfiguration;
+
 export type ConfigStoreHydrationPacket<T extends Entry> = {
   entries: Record<string, T>;
   environment: Environment;

src/persistent-configuration-storage.ts

@@ -1,24 +1,23 @@
-import { IConfiguration } from './i-configuration';
+import { Configuration } from './i-configuration';
 
 /**
  * Persistent configuration storages are responsible for persisting
  * configuration between SDK reloads.
  */
-// TODO: replace `IConfiguration` with a concrete `Configuration` type.
 export interface PersistentConfigurationStorage {
   /**
    * Load configuration from the persistent storage.
    *
    * The method may fail to load a configuration or throw an
    * exception (which is generally ignored).
    */
-  loadConfiguration(): PromiseLike<IConfiguration | null>;
+  loadConfiguration(): PromiseLike<Configuration | null>;
 
   /**
    * Store configuration to the persistent storage.
    *
    * The method is allowed to do async work (which is not awaited) or
    * throw exceptions (which are ignored).
    */
-  storeConfiguration(configuration: IConfiguration | null): void;
+  storeConfiguration(configuration: Configuration | null): void;
 }