AspNetCore AddApplicationInsightsSettings() and MissingMethodException

[TimothyMothra]

This was brought to my attention by @brettsam

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In AppInsights.AspNetCore 2.12.0 I changed the method signature of AddApplicationInsightsSettings by adding the optional parameter connectionString.

ApplicationInsights-dotnet/NETCORE/src/Shared/Extensions/ApplicationInsightsExtensions.cs

Lines 163 to 168 in 0076e0f

	public static IConfigurationBuilder AddApplicationInsightsSettings(
	this IConfigurationBuilder configurationSourceRoot,
	bool? developerMode = null,
	string endpointAddress = null,
	string instrumentationKey = null,
	string connectionString = null)

This can cause a MissingMethodException for users upgrading from an older version of our SDK.
(Explanation of MissingMethodException and default parameters: https://stackoverflow.com/a/9884700/1466768)

Next Steps

I think this will be a straightforward fix, I should be able to add a method overload matching the signature of the original method.
I'm setting up a repro right now so I can verify a fix.
The plan is to release a patch for versions 2.12, 2.13, and 2.14

Next Next Steps

This highlights the need to add a PublicApiAnalyzer to our other projects.
We currently only have this analyzer on 2/17 of our projects.

[TimothyMothra]

I have a repro and I'm verifying the fix.

I'm trying to keep both method signatures (old and new), but this can cause AmbiguousMatchException.

I think the solution is going to look like this:

        public static IConfigurationBuilder AddApplicationInsightsSettings(
            this IConfigurationBuilder configurationSourceRoot,  
            bool? developerMode = null, 
            string endpointAddress = null, 
            string instrumentationKey = null)
            => configurationSourceRoot.AddApplicationInsightsSettings(developerMode, endpointAddress, instrumentationKey);

        public static IConfigurationBuilder AddApplicationInsightsSettings(
            this IConfigurationBuilder configurationSourceRoot,
            string connectionString,
            bool? developerMode = null,
            string endpointAddress = null,
            string instrumentationKey = null)
        {

Note that connectionString can't be an optional parameter because that causes the Ambiguous exception.
The only fix is going to be moving it to the first parameter, which will be a breaking change for anybody who took a dependency on it being the last. :(
Anyone who used named parameters would be immune to this problem.
Fun times.

[TimothyMothra]

The fix has been published to NuGet and should be generally available within an hour.

• https://www.nuget.org/packages/Microsoft.ApplicationInsights.AspNetCore/2.12.2
• https://www.nuget.org/packages/Microsoft.ApplicationInsights.AspNetCore/2.13.1
• https://www.nuget.org/packages/Microsoft.ApplicationInsights.AspNetCore/2.14.0-beta2