chore: add a typing declaration file

index.d.ts

@@ -0,0 +1,43 @@
+declare module 'osmose-request' {
+
+  export interface Item {
+    id: number;
+    name: string;
+    tags: string[];
+    count: number[] | null;
+    levels: number[];
+  }
+
+  export interface Category {
+    id: number;
+    name: string;
+    items: Item[];
+  }
+
+  export interface Error {
+    [key: string]: string;
+  }
+
+  export interface Options {
+    language?: string;
+    endpoint?: string;
+  }
+
+  export default class OsmoseRequest {
+    constructor(options?: Options);
+
+    closeError(errorId: number | string): Promise<boolean>;
+
+    falseError(errorId: number | string): Promise<boolean>;
+
+    fetchError(errorId: number | string): Promise<Error>;
+
+    fetchErrors(params: {}): Promise<Error[]>;
+
+    fetchItemCategories(): Promise<Category[]>;
+
+    fetchItems(isoCountryCode?: string): Promise<Item[]>;
+
+    fetchSupportedCountries(): string[];
+  }
+}

package.json

@@ -17,8 +17,10 @@
     "api"
   ],
   "main": "dist/OsmoseRequest.js",
+  "types": "index.d.ts",
   "files": [
-    "dist"
+    "dist",
+    "index.d.ts"
   ],
   "scripts": {
     "watch": "webpack -w --progress",