EF Core class library and migrations in azure pipeline - entity-framework

Question

I know that to use EF Core in a class library a startup project is needed, as explained here: Is EF Core Add Migration Supported from .NET Standard Library?
However, I've managed to use dotnet ef migrations bundle locally using a single class library project (without using a startup project) by
Adding a ConfigurationBuilder you dbcontext
Overriding the "OnConfiguring" method to use the ConfigurationBuilder for reading the connection string where you have it. In my case from user secrets
public partial class MyContext : DbContext
{
private readonly IConfiguration configuration;
//will take the connection string from user secrets
public MyContext()
{
this.configuration = new ConfigurationBuilder()
.AddUserSecrets<ClpQUkMiContext>()
.Build();
}
public MyContext(IConfiguration configuration)
{
this.configuration = configuration;
}
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
if (!optionsBuilder.IsConfigured)
{
var connectionString = configuration["ConnectionStringInUserSecret"]
optionsBuilder.UseSqlServer(connectionString);
}
}
However, when I'm trying to use it in azure pipeline it's failing to find the connection string, which I have stored in a secret variable.
So far I've tried
Adding ".AddEnvironmentVariables()" to the configuration builder.
Mapping the secret variable in the yaml file, like
variables:
MyConnectionString: $(MySecreatConnectionString) # Setting variable to be read by the context
I would appreciate any help.

Answer 1

Managed to solve the issue: To map a secret variable into an environment one that can be read by the configuration, it must be done inside each task, as crlearly explained here: https://learn.microsoft.com/en-us/azure/devops/pipelines/process/variables?view=azure-devops&tabs=yaml%2Cbatch#secret-variables
dev variable inside the task