Heroku Postgres Maintenance change env var and break the app

Question

I deployed a NodeJS application to Heroku and attach to it a Postgres database with Heroku Postgres addons, all was working perfectly. After a few hours, I was unable to authenticate my application. After checking the logs, I understand that the application is unable to connect to the database because of a wrong password. After that, I also got 2 emails from Heroku that alert me of the maintenance.

So I checked the credentials database and the credentials are all the same except the URI. I also checked on my env vars and I saw that Heroku added 2 more variables HEROKU_DATABASE_URL and HEROKU_POSTGRESQL_CRIMSON_URL, I tried to edit them with the new URI of the updated Database but do have permission ...

I also tried to delete and recreate a new database but every time the Heroku Maintenance come back and break my app

Here is my connection code to Postgres (using nest js)

TypeOrmModule.forRootAsync({
  imports: [ConfigModule],
  inject: [ConfigService],
  useFactory: async (configService: ConfigService) => {
    const isProduction = configService.get('STAGE') === 'prod';

    return {
      ssl: isProduction,
      extra: {
        ssl: isProduction ? { rejectUnauthorized: false } : null,
      },
      type: 'postgres',
      autoLoadEntities: true,
      synchronize: true,
      host: configService.get('DB_HOST'),
      port: configService.get('DB_PORT'),
      username: configService.get('DB_USERNAME'),
      password: configService.get('DB_PASSWORD'),
      database: configService.get('DB_DATABASE'),
    };
  },
}),

Here is the error i get

ERROR [ExceptionHandler] password authentication failed for user "ryooypezxslwmn"

Answer 1

Heroku Postgres provides and maintains one environment variable per provisioned database:

As part of the provisioning process, a DATABASE_URL config var is added to your app’s configuration. DATABASE_URL contains the URL your app uses to access the database. If your app already has a Heroku Postgres database and you’ve provisioned another one, this config var’s name instead has the format HEROKU_POSTGRESQL_<COLOR>_URL (for example, HEROKU_POSTGRESQL_YELLOW_URL).

When your database connection string needs to change, Heroku automatically updates the DATABASE_URL and HEROKU_POSTGRESQL_<COLOR>_URL variables.

But you aren't using these variables. The DB_HOST, DB_PORT, etc., environment variables aren't set by Heroku, and Heroku won't update them for you. Rather than manually setting those variables, I strongly urge you to use the variables Heroku provides:

The value of your app’s DATABASE_URL config var can change at any time. Do not rely on this value either inside or outside your Heroku app.

I'm not familiar with TypeORM, but it looks like you can pass it a url directly:

TypeOrmModule.forRootAsync({
  imports: [ConfigModule],
  inject: [ConfigService],
  useFactory: async (configService: ConfigService) => {
    const isProduction = configService.get('STAGE') === 'prod';

    return {
      ssl: isProduction,
      extra: {
        ssl: isProduction ? { rejectUnauthorized: false } : null,
      },
      type: 'postgres',
      autoLoadEntities: true,
      synchronize: true,
      url: configService.get('DATABASE_URL'),  // <-- here
    };
  },
}),