auth: adds token-auth to public api

adds auth service
adds auth module
adds token-auth strategy
adds token-auth to all public api calls

Signed-off-by: Philip Molares <philip.molares@udo.edu>

src/auth/token.strategy.ts

@@ -0,0 +1,26 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { Strategy } from 'passport-http-bearer';
+import { PassportStrategy } from '@nestjs/passport';
+import { Injectable, UnauthorizedException } from '@nestjs/common';
+import { AuthService } from './auth.service';
+import { User } from '../users/user.entity';
+
+@Injectable()
+export class TokenStrategy extends PassportStrategy(Strategy, 'token') {
+  constructor(private authService: AuthService) {
+    super();
+  }
+
+  async validate(token: string): Promise<User> {
+    const user = await this.authService.validateToken(token);
+    if (!user) {
+      throw new UnauthorizedException();
+    }
+    return user;
+  }
+}