Begin consumption of API

exam/react/src/api/Api.ts

@@ -0,0 +1,61 @@
+import { User } from '../types/User';
+
+const BASE = 'https://khofmann.userpage.fu-berlin.de/phpCourse/exam/api/';
+
+let instance: ApiImpl;
+
+class ApiImpl {
+  private token: string = '';
+
+  constructor() {
+    if (instance) {
+      throw new Error('New instance cannot be created!!');
+    }
+
+    instance = this;
+  }
+
+  public logIn = async (email: string, password: string): Promise<User> => {
+    const { user, token } = await (await this.post('login', { email, password })).json();
+    this.token = token;
+
+    return user;
+  };
+
+  public logOut = async (): Promise<boolean> => {
+    return await (await this.postAuth('logout')).json();
+  };
+
+  private post = async (
+    endpoint: string,
+    body: Record<string, unknown> | undefined = undefined,
+    headers: HeadersInit | undefined = undefined
+  ) => {
+    const response = await fetch(`${BASE}${endpoint}`, {
+      mode: 'cors',
+      method: 'post',
+      headers,
+      body: JSON.stringify(body),
+    });
+    if (response.ok) return response;
+    throw await response.json();
+  };
+
+  private postAuth = async (
+    endpoint: string,
+    body: Record<string, unknown> | undefined = undefined,
+    headers: HeadersInit | undefined = undefined
+  ) => {
+    const response = await fetch(`${BASE}${endpoint}`, {
+      mode: 'cors',
+      method: 'post',
+      headers: { token: this.token, ...headers },
+      body: JSON.stringify(body),
+    });
+    if (response.ok) return response;
+    throw await response.json();
+  };
+}
+
+const Api = new ApiImpl();
+export default Api;