BinaryFormatter deprecation for System.Configuration.ConfigurationManager

[pgovind]

This is a draft PR to turn off the BinaryFormatter code paths by default in System.Configuration.ConfigurationManager. Essentially all I'm doing here is deprecating SettingsSerializeAs.Binary and hiding the BinaryFormatter related code paths behind an AppContext switch.

@buyaa-n @joperezr @krwq @safern @steveharter @maryamariyan (these are the current/past area-owners). I'm not super familiar with this area so I'd like feedback about the approach here from the area owners. Specifically, if you can think of the following, that would be super appreciated:

1. Scenarios that this PR breaks (I can't think of any since no code is being deleted and current behavior is enabled by the AppContext switch)
2. Test cases I haven't added
3. Anything else that I've missed

This is NOT the most minimal change. We might be able to get away with just marking SettingsSerializeAs.Binary as Obsolete. I, however, chose to be more conservative and hid all the BinaryFormatter code paths behind an AppContext switch since this way we actually deprecate the BinaryFormatter code paths.

Fixes #39295

cc @GrabYourPitchforks

[ghost]

Tagging subscribers to this area: @safern
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Issue Details

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This is a draft PR to turn off the BinaryFormatter code paths by default in System.Configuration.ConfigurationManager. Essentially all I'm doing here is deprecating SettingsSerializeAs.Binary and hiding the BinaryFormatter related code paths behind an AppContext switch.

@buyaa-n @joperezr @krwq @safern @steveharter @maryamariyan (these are the current/past area-owners). I'm not super familiar with this area so I'd like feedback about the approach here from the area owners. Specifically, if you can think of the following, that would be super appreciated:

1. Scenarios that this PR breaks
2. Test cases I haven't added
3. Anything else that I've missed

This is NOT the most minimal change. We might be able to get away with just marking SettingsSerializeAs.Binary as Obsolete. I, however, chose to be more conservative and hid all the BinaryFormatter code paths behind an AppContext switch.

Fixes #39295

cc @GrabYourPitchforks

Author:	pgovind
Assignees:	-
Labels:	area-System.Configuration
Milestone:	-

[pgovind]

Friendly ping for @buyaa-n @joperezr @krwq @safern @steveharter @maryamariyan @GrabYourPitchforks

[pgovind]

Reset changes to this file

[pgovind]

@steveharter : I'm guessing you have the most context with this library at the moment?

[steveharter]

Note the test failure in CI (not support on .NET Framework)

C:\h\w\BF4A0985\w\9FE508EC\e>xunit.console.exe System.Configuration.ConfigurationManager.Tests.dll -xml testResults.xml -nologo -nocolor -noappdomain -maxthreads 1 -notrait category=IgnoreForCI -notrait category=OuterLoop -notrait category=failing  
  Discovering: System.Configuration.ConfigurationManager.Tests (app domain = off, method display = ClassAndMethod, method display options = None)
  Discovered:  System.Configuration.ConfigurationManager.Tests (found 485 of 506 test cases)
  Starting:    System.Configuration.ConfigurationManager.Tests (parallel test collections = on, max threads = 1)
    System.ConfigurationTests.BinaryFormatterDeprecationTests.SerializeAndDeserializeWithSettingsSerializeAsBinary [FAIL]
      System.InvalidOperationException : RuntimeConfigurationOptions are only supported on .NET Core
      Stack Trace:
        /_/src/Microsoft.DotNet.RemoteExecutor/src/RemoteExecutor.cs(395,0): at Microsoft.DotNet.RemoteExecutor.RemoteExecutor.GetConsoleAppArgs(RemoteInvokeOptions options, IEnumerable`1& toDispose)
        /_/src/Microsoft.DotNet.RemoteExecutor/src/RemoteExecutor.cs(368,0): at Microsoft.DotNet.RemoteExecutor.RemoteExecutor.Invoke(MethodInfo method, String[] args, RemoteInvokeOptions options, Boolean pasteArguments)
        /_/src/libraries/System.Configuration.ConfigurationManager/tests/System/Configuration/BinaryFormatterDeprecationTests.cs(29,0): at System.ConfigurationTests.BinaryFormatterDeprecationTests.SerializeAndDeserializeWithSettingsSerializeAsBinary()
  Finished:    System.Configuration.ConfigurationManager.Tests

[maryamariyan]

Do we also care about adding a test case using reflection as well?

cc: @GrabYourPitchforks

[pgovind]

I think in general we don't care about binary formatter usage if it is called explicitly via reflection by a user.

[maryamariyan]

LGTM, aside from CI test issues