fix

lib/DatabaseModel.ts

@@ -9,19 +9,19 @@ export abstract class DatabaseModel {
   protected data: Record<string, string|number|boolean> = {};
 
   public get id (): number {
-    return this.data.id;
+    return this.data.id as number;
   }
 
   public set id (val: number) {
     this.data.id = val;
   }
 
-  public constructor (id) {
+  public constructor (id: number) {
     this.id = id;
   }
 
   public abstract get(key: string): string|number|boolean;
-  public abstract set(key: string, value: string|number|boolean);
+  public abstract set(key: string, value: string|number|boolean): void;
 
   public abstract async read(): Promise<void>;
   public abstract async write(): Promise<void>;