Transient Failure handling in .net core 2.1 MVC for MySQL Database

问题

services.AddDbContext<MyContext>(options =>
{
    options.UseSqlServer(mysqlConnection,
    sqlServerOptionsAction: sqlOptions =>
    {
        sqlOptions.EnableRetryOnFailure(
        maxRetryCount: 10,
        maxRetryDelay: TimeSpan.FromSeconds(30),
        errorNumbersToAdd: null);
    });
});

I found this code snippet at:

https://docs.microsoft.com/en-us/dotnet/standard/microservices-architecture/implement-resilient-applications/implement-resilient-entity-framework-core-sql-connections

My DB is MySQL 5.7

I changed the above code to :

That means EnableRetryOnFailure is not available for MySQL DB. How do i set the retry, delay etc.. policies now?

Also if i try to set the ExecutionStrategy function i get this:

Then i tried Create my own Strategy using:

public class MyStrategy: ExecutionStrategy
{
   ......
}

but how to use this class now?

回答1:

There is a library for this: https://github.com/PomeloFoundation/Pomelo.EntityFrameworkCore.MySql

Setup steps:

1. Donwload Pomelo.EntityFrameworkCore.MySql from NuGet.

2. Add this using to your class:

   using Pomelo.EntityFrameworkCore.MySql.Infrastructure;

3. Add this to your ConfigureServices method:

   services.AddDbContextPool<ApplicationDbContext>( 
   options => options.UseMySql("Server=localhost;Database=ef;User=root;Password=123456;",
   
       mySqlOptions =>
       {
           mySqlOptions.ServerVersion(new Version(5, 7, 17), ServerType.MySql)
           .EnableRetryOnFailure(
           maxRetryCount: 10,
           maxRetryDelay: TimeSpan.FromSeconds(30),
           errorNumbersToAdd: null); 
       }
   ));
   

来源：https://stackoverflow.com/questions/55432473/transient-failure-handling-in-net-core-2-1-mvc-for-mysql-database