Deploying asp.net core self-contained web app to Ubuntu. Database name empty when present in appsettings.json

I just set up a LAMP server VM on Digital Ocean. OS is Ubuntu 18.04 x64. MySQL is 5.7.23. I also have a published to a local folder asp.net core web application, which I have set to Ubuntu 18.04-x64. I copied the files from the local folder to var/MyApp on the server and set chmod +x on the executable file. I also changed the MySql root password and created a database named limboworld. My application is set to run all migrations on startup. However when I start it with ./catchme.bg I get the following output with an error shown below.

I tried changing the MySql password and also the connection string from:

"catchmebgContextConnection": "Server=localhost;Database=limboworld;User=root;Password=limboworld;"

to

"catchmebgContextConnection": "Server=localhost;Database=limboworld;Uid=root;Pwd=limboworld;"

info: Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager[0]
      User profile is available. Using '/root/.aspnet/DataProtection-Keys' as key repository; keys will not be encrypted at rest.
info: Microsoft.EntityFrameworkCore.Infrastructure[10403]
      Entity Framework Core 2.1.11-servicing-32099 initialized 'catchmebgContext' using provider 'Pomelo.EntityFrameworkCore.MySql' with options: MaxPoolSize=128 ServerVersion 5.7.24 MySql
fail: Microsoft.EntityFrameworkCore.Database.Connection[20004]
      An error occurred using the connection to database '' on server 'localhost'.
MySql.Data.MySqlClient.MySqlException (0x80004005): Access denied for user 'root'@'localhost'
   ...
Application startup exception: MySql.Data.MySqlClient.MySqlException (0x80004005): Access denied for user 'root'@'localhost'
   at MySqlConnector.Core.ServerSession.ConnectAsync(ConnectionSettings cs, ILoadBalancer loadBalancer, IOBehavior ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\Core\ServerSession.cs:line 356
   at MySql.Data.MySqlClient.MySqlConnection.CreateSessionAsync(Nullable`1 ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlConnection.cs:line 442
   at MySql.Data.MySqlClient.MySqlConnection.OpenAsync(Nullable`1 ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlConnection.cs:line 175
   at MySql.Data.MySqlClient.MySqlConnection.Open() in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlConnection.cs:line 161
   at Microsoft.EntityFrameworkCore.Storage.RelationalConnection.OpenDbConnection(Boolean errorsExpected)
   at Microsoft.EntityFrameworkCore.Storage.RelationalConnection.Open(Boolean errorsExpected)
   at Pomelo.EntityFrameworkCore.MySql.Storage.Internal.MySqlDatabaseCreator.<>c__DisplayClass18_0.<Exists>b__0(DateTime giveUp)
   at Microsoft.EntityFrameworkCore.ExecutionStrategyExtensions.<>c__DisplayClass12_0`2.<Execute>b__0(DbContext c, TState s)
   at Pomelo.EntityFrameworkCore.MySql.Storage.Internal.MySqlExecutionStrategy.Execute[TState,TResult](TState state, Func`3 operation, Func`3 verifySucceeded)
   at Microsoft.EntityFrameworkCore.ExecutionStrategyExtensions.Execute[TState,TResult](IExecutionStrategy strategy, Func`2 operation, Func`2 verifySucceeded, TState state)
   at Pomelo.EntityFrameworkCore.MySql.Storage.Internal.MySqlDatabaseCreator.Exists(Boolean retryOnNotExists)
   at Microsoft.EntityFrameworkCore.Migrations.HistoryRepository.Exists()
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.Migrate(String targetMigration)
   at catchme.bg.Startup.Configure(IApplicationBuilder app, IHostingEnvironment env, catchmebgContext db1, CatchmeContext db2) in C:\Users\Ivan\Source\repos\catchme.bg\catchme.bg\catchme.bg\Startup.cs:line 84
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Hosting.ConventionBasedStartup.Configure(IApplicationBuilder app)
   at Microsoft.AspNetCore.Hosting.Internal.WebHost.BuildApplication()
crit: Microsoft.AspNetCore.Hosting.Internal.WebHost[6]
      Application startup exception
MySql.Data.MySqlClient.MySqlException (0x80004005): Access denied for user 'root'@'localhost'
   at MySqlConnector.Core.ServerSession.ConnectAsync(ConnectionSettings cs, ILoadBalancer loadBalancer, IOBehavior ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\Core\ServerSession.cs:line 356
   at MySql.Data.MySqlClient.MySqlConnection.CreateSessionAsync(Nullable`1 ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlConnection.cs:line 442
   at MySql.Data.MySqlClient.MySqlConnection.OpenAsync(Nullable`1 ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlConnection.cs:line 175
   at MySql.Data.MySqlClient.MySqlConnection.Open() in C:\projects\mysqlconnector\src\MySqlConnector\MySql.Data.MySqlClient\MySqlConnection.cs:line 161
   at Microsoft.EntityFrameworkCore.Storage.RelationalConnection.OpenDbConnection(Boolean errorsExpected)
   at Microsoft.EntityFrameworkCore.Storage.RelationalConnection.Open(Boolean errorsExpected)
   at Pomelo.EntityFrameworkCore.MySql.Storage.Internal.MySqlDatabaseCreator.<>c__DisplayClass18_0.<Exists>b__0(DateTime giveUp)
   at Microsoft.EntityFrameworkCore.ExecutionStrategyExtensions.<>c__DisplayClass12_0`2.<Execute>b__0(DbContext c, TState s)
   at Pomelo.EntityFrameworkCore.MySql.Storage.Internal.MySqlExecutionStrategy.Execute[TState,TResult](TState state, Func`3 operation, Func`3 verifySucceeded)
   at Microsoft.EntityFrameworkCore.ExecutionStrategyExtensions.Execute[TState,TResult](IExecutionStrategy strategy, Func`2 operation, Func`2 verifySucceeded, TState state)
   at Pomelo.EntityFrameworkCore.MySql.Storage.Internal.MySqlDatabaseCreator.Exists(Boolean retryOnNotExists)
   at Microsoft.EntityFrameworkCore.Migrations.HistoryRepository.Exists()
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.Migrate(String targetMigration)
   at catchme.bg.Startup.Configure(IApplicationBuilder app, IHostingEnvironment env, catchmebgContext db1, CatchmeContext db2) in C:\Users\Ivan\Source\repos\catchme.bg\catchme.bg\catchme.bg\Startup.cs:line 84
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Hosting.ConventionBasedStartup.Configure(IApplicationBuilder app)
   at Microsoft.AspNetCore.Hosting.Internal.WebHost.BuildApplication()
Hosting environment: Production
Content root path: /var/MyApp
Now listening on: http://localhost:5000
Application started. Press Ctrl+C to shut down.

I would like to connect to the database on application startup and run the migrations. However because of the above error it doesn't work.

Any ideas would be very helpful!

It turned out MySql 5.7 uses a plugin named 'auth_socket', which enables the root user to login to mysql with no password.

This line sets a password 'test' for the root account:

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'test';

After setting the password in the appsettings.json and appsettings.production.json files, everything worked correctly!

Here is the link, that I used to fix the problem:

https://www.percona.com/blog/2016/03/16/change-user-password-in-mysql-5-7-with-plugin-auth_socket/

Thank you all for looking at my question!