feat: auth routes and service

back/src/auth/auth.service.ts

@@ -0,0 +1,32 @@
+import { Injectable } from '@nestjs/common';
+import { UsersService } from '../users/users.service';
+import { JwtService } from '@nestjs/jwt';
+import * as bcrypt from 'bcryptjs';
+import PayloadInterface from './interface/payload.interface';
+@Injectable()
+export class AuthService {
+
+	constructor(
+		private userService: UsersService,
+		private jwtService: JwtService
+	) {}
+
+	async validateUser(username: string, password: string): Promise<PayloadInterface> {
+    const user = await this.userService.user({username});
+		if (user && bcrypt.compareSync(password, user.password)) {
+			return {
+				username: user.username,
+				id: user.id
+			};
+		}
+		return null;
+	}
+
+	async login(user: PayloadInterface) {
+		const payload = { username: user.username, id: user.id };
+		const access_token = this.jwtService.sign(payload);
+		return {
+		  access_token
+		};
+	}
+}