Added user login & registration. Added SQL file for postgres database.

backend/nestjs-seshat-api/src/auth/auth.service.ts

@@ -0,0 +1,42 @@
+import { Injectable } from '@nestjs/common';
+import { UserEntity } from 'src/users/users.entity';
+import { UsersService } from 'src/users/users.service';
+import { AuthRefreshService } from './auth.refresh.service';
+import { AuthAccessService } from './auth.access.service';
+
+@Injectable()
+export class AuthService {
+  constructor(
+    private accessTokens: AuthAccessService,
+    private refreshTokens: AuthRefreshService,
+    private users: UsersService,
+  ) { }
+
+
+  async login(user: UserEntity) {
+    return this.renew(user, null);
+  }
+
+  async validate(
+    username: string,
+    password: string,
+  ): Promise<UserEntity | null> {
+    return await this.users.findOne({ username, password });
+  }
+
+  async renew(
+    user: UserEntity,
+    refresh_token: string
+  ): Promise<{ access_token: string, exp: number, refresh_token: string, refresh_exp: number }> {
+    const new_refresh_data = await this.refreshTokens.generate(user, refresh_token);
+    const new_refresh_token = new_refresh_data.refresh_token;
+    const new_refresh_exp = new_refresh_data.exp;
+    const access_token = await this.accessTokens.generate(user);
+
+    return {
+      ...access_token,
+      refresh_token: new_refresh_token,
+      refresh_exp: new_refresh_exp,
+    }
+  }
+}