How do you configure logging scopes in MvvmCross

Understanding Logging Scopes

Logging scopes are useful for grouping a set of logical operations and attaching the same data to each log entry within that scope. This is particularly helpful for filtering or analyzing logs related to specific tasks or transactions.

Implementing Logging Scopes in MvvmCross

1. Setup and Configuration:
- In MvvmCross, you need to override the `CreateLogProvider` and `CreateLogFactory` methods in your `MvxSetup` class to configure logging. This setup is typically done in the platform-specific project (e.g., Android, iOS, WPF).
- For example, you might use Serilog as your logging provider, which is a popular choice for .NET applications, including MvvmCross.

2. Using ILoggerFactory:
- You can inject an `ILoggerFactory` into your classes to create loggers as needed. This is useful for creating non-scoped logs or multiple loggers.
- To use scopes, you typically work with an `ILogger` instance, which can be injected into your view models or services.

3. Creating a Scope:
- To create a logging scope, you use the `BeginScope` method of the `ILogger` instance. This method returns an `IDisposable` object that defines the scope.
- You wrap your logging operations within a `using` block to ensure the scope is properly disposed of when you're done.

Example Configuration

Here's how you might configure logging scopes in a MvvmCross application:

Setup Class

First, configure your logging setup class to use a specific logging provider like Serilog:

csharp
public class Setup : MvxWpfSetup
{
    protected override ILoggerProvider CreateLogProvider()
    {
        return new SerilogLoggerProvider();
    }

    protected override ILoggerFactory CreateLogFactory()
    {
        Log.Logger = new LoggerConfiguration()
            .MinimumLevel.Debug()
            .CreateLogger();

        return new SerilogLoggerFactory();
    }
}

Using Scopes in ViewModels

Then, in your view models, you can use scopes to group related log entries:

csharp
public class MyViewModel : MvxViewModel
{
    private readonly ILogger _logger;

    public MyViewModel(ILogger logger)
    {
        _logger = logger;
    }

    public void SomeMethod()
    {
        var transactionId = Guid.NewGuid().ToString();

        using (_logger.BeginScope(new List>
        {
            new KeyValuePair("TransactionId", transactionId),
        }))
        {
            _logger.LogInformation("Starting transaction {TransactionId}", transactionId);
            // Perform transaction operations
            _logger.LogInformation("Completed transaction {TransactionId}", transactionId);
        }
    }
}

In this example, all log entries within the `using` block will include the `TransactionId`, making it easier to filter or analyze logs related to this specific transaction.

Conclusion

Configuring logging scopes in MvvmCross involves leveraging the `Microsoft.Extensions.Logging` framework to create scopes that group related log entries. By using `ILoggerFactory` and `ILogger` instances, you can effectively manage and analyze logs in your cross-platform applications.