IOptionsMonitor in example doesn't update config in existing Loggers

[hannahchan]

The current example for ColorConsoleLoggerProvider which usesIOptionsMonitor<ColorConsoleLoggerConfiguration> doesn't update the config for existing loggers that have already been instantiated and stored in _loggers. When the configuration changes, these loggers continue to reference the old ColorConsoleLoggerConfiguration instance and only the new instances take on the configuration change.

One suggestion to fix this is to update the following line in the constructor from;

_onChangeToken = config.OnChange(updatedConfig => _currentConfig = updatedConfig);

to;

_onChangeToken = config.OnChange(updatedConfig =>
{
    _currentConfig = updatedConfig;
    _loggers.Clear();
});

Other than that, I'm wondering if there are best practices that other developers like me should know about when implementing a custom logging provider. For example, how to make an async HTTP request to a logging backend.

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Document Details

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• ID: b609eb80-71e8-7a3c-4c4c-60cf9a315cfb
• Version Independent ID: e111baf5-04b7-c497-ce86-eb687e121751
• Content: Implement a custom logging provider in .NET
• Content Source: docs/core/extensions/custom-logging-provider.md
• Product: dotnet-fundamentals
• GitHub Login: @IEvangelist
• Microsoft Alias: dapine

[IEvangelist]

Hi 👋 @hannahchan
Thank you so much for posting this issue. We really appreciate it.

You're absolutely right, this is a bug in the example code - I'll work on updating this article and report back when the fix is merged. Thanks again

[IEvangelist]

Hi again @hannahchan - what do you think about #24774?

[hannahchan]

Hi again @hannahchan - what do you think about #24774?

Looks good to me. Awesome work! Thanks.