chore: Support $(JsonSerializerIsReflectionEnabledByDefault)=false

[jonpryor]

Context: #2970
Context: #3001

Fixes: #2908

When $(JsonSerializerIsReflectionEnabledByDefault)=false,
then various JsonSerializer methods will throw.

For example:

partial class SerializerExtensionsTests {
  [TestMethod]
  public void ToFromStringTest()
  {
    var services    = new ServiceCollection().BuildServiceProvider();
    var Serializer  = new SystemTextJsonSerializer(services);
    var classEntity = new SimpleClass { SimpleTextProperty = SimpleText + "Hello World!Class" };
    var stringValue = Serializer.ToString(classEntity);
    // …
  }
}

Fails with:

  Failed ToFromStringTest [< 1 ms]
  Error Message:
   Test method Uno.Extensions.Serialization.Tests.SerializerExtensionsTests.ToFromStringTest threw exception:
System.InvalidOperationException: Reflection-based serialization has been disabled for this application. Either use the source generator APIs or explicitly configure the 'JsonSerializerOptions.TypeInfoResolver' property.
  Stack Trace:
   at System.Text.Json.ThrowHelper.ThrowInvalidOperationException_JsonSerializerIsReflectionDisabled()
   at System.Text.Json.JsonSerializerOptions.ConfigureForJsonSerializer()
   at System.Text.Json.JsonSerializer.GetTypeInfo(JsonSerializerOptions options, Type inputType)
   at System.Text.Json.JsonSerializer.Serialize(Object value, Type inputType, JsonSerializerOptions options)
   at Uno.Extensions.Serialization.SystemTextJsonSerializer.ToString(Object value, Type valueType) in /Volumes/Xamarin-Work/src/unoplatform/uno.extensions/src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs:line 101
   at Uno.Extensions.Serialization.SerializerExtensions.ToString[T](ISerializer serializer, T value) in /Volumes/Xamarin-Work/src/unoplatform/uno.extensions/src/Uno.Extensions.Serialization/SerializerExtensions.cs:line 24
   at Uno.Extensions.Serialization.Tests.SerializerExtensionsTests.ToFromStringTest() in /Volumes/Xamarin-Work/src/unoplatform/uno.extensions/src/Uno.Extensions.Serialization.Tests/StreamSerializerExtensionsTests.cs:line 66
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
   at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)

The question: how should this work? How can it work?

The ASP.NET Core support for Native AOT > Changes to support source generation
documentation section provides some ideas for how this can work.

The fundamental point: if Reflection based JSON (de)serialization
cannot be used, and the suggested alternative is to use
System.Text.Json source generation, then there needs to be a way
for the framework to use the generated code.

In the ASP.NET Core docs, they suggest using the
HttpJsonServiceExtensions.ConfigureHttpJsonOptions() extension
method during service configuration:

var builder = WebApplication.CreateSlimBuilder(args);
builder.Services.ConfigureHttpJsonOptions(options =>
{
  options.SerializerOptions.TypeInfoResolverChain.Insert(0, AppJsonSerializerContext.Default);
});

// …

[JsonSerializable(typeof(Todo[]))]
internal partial class AppJsonSerializerContext : JsonSerializerContext
{
}

In order to work when
$(JsonSerializerIsReflectionEnabledByDefault)=false,
Uno.Extensions.Serialization needs a similar mechanism, a way to
provide the generated JsonSerializerContext types to
Uno.Extensions.Serialization.

Draw inspiration from ASP.NET Core:

• https://github.com/dotnet/dotnet/blob/9add30f0238eabacba9a92acec51a8d714fd1881/src/aspnetcore/src/Http/Http.Extensions/src/JsonOptions.cs
• https://github.com/dotnet/dotnet/blob/9add30f0238eabacba9a92acec51a8d714fd1881/src/aspnetcore/src/Http/Http.Extensions/src/HttpJsonServiceExtensions.cs#L23-L27
• https://github.com/dotnet/dotnet/blob/9add30f0238eabacba9a92acec51a8d714fd1881/src/aspnetcore/src/Http/Http.Extensions/src/HttpRequestJsonExtensions.cs#L397-L401

The core of the new mechanism mirrors what ASP.NET Core does:

public partial class JsonSerializationOptions {
  public JsonSerializerOptions SerializerOptions { get; }
}
public partial class ServiceCollectionExtensions {
  public static IServiceCollection ConfigureJsonSerializationOptions(this IServiceCollection services, Action<SerializationOptions> configureOptions);
  public static IServiceCollection AddJsonSerialization(this IServiceCollection services, HostBuilderContext context, params IEnumerable<IJsonTypeInfoResolver> typeInfoResolvers);
  public static IServiceCollection AddJsonTypeInfo(this IServiceCollection services, params IEnumerable<IJsonTypeInfoResolver> typeInfoResolvers);
}
public partial class HostBuilderExtensions {
  public static IHostBuilder UseSerialization(this IHostBuilder hostBuilder, IEnumerable<IJsonTypeInfoResolver> typeInfoResolvers, Action<IServiceCollection> configure);
  public static IHostBuilder UseSerialization(this IHostBuilder hostBuilder, IEnumerable<IJsonTypeInfoResolver> typeInfoResolvers, Action<HostBuilderContext, IServiceCollection>? configure = default);
}

This allows adding the generated *SerializationContext.Default
properties for subsequent use:

hostBuilder.UseSerialization([AppJsonSerializerContext.Default]);

To lead developers to the new APIs, the existing
IHostBuilder.UseSerialization() and
IServiceCollection.AddSystemTextJsonSerialization(), extension
methods have been marked with [RequiresDynamicCode] and
[RequiresUnreferencedCode], as a way to notify developers of the
new mechanism. This will result in build warnings:

warning IL3050: Using member 'Uno.Extensions.HostBuilderExtensions.UseSerialization(IHostBuilder, Action<HostBuilderContext, IServiceCollection>)' which has 'RequiresDynamicCodeAttribute' can break functionality when AOT compiling.
  Default behavior requires Reflection.
  For trimming support, use: UseSerialization(IHostBuilder, IEnumerable<IJsonTypeInfoResolver>, Action<HostBuilderContext, IServiceCollection>).

To test this, add a new src/Uno.Extensions.Serialization.AotTests
test project which:

1. Sets $(JsonSerializerIsReflectionEnabledByDefault)=false, and
2. Defines WITH_AOT_TRIMMING, and
3. Imports all the C# source from
   src/Uno.Extensions.Serialization.Tests.

The WITH_AOT_TRIMMING define allows us to use the same set of
serialization tests for both untrimmed and trimmed environments.

Update stage-build-packages.yml so that *.AotTests.dll are also
executed by VSTest@2.

Additionally, enable $(IsAotCompatible)=true for:

• src/Uno.Extensions.Serialization/Uno.Extensions.Serialization.csproj

Address the following warnings:

src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(120,14): error IL2046:
  Member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.ToString(Object, Type)' with 'RequiresUnreferencedCodeAttribute' implements interface member 'Uno.Extensions.Serialization.ISerializer.ToString(Object, Type)' without 'RequiresUnreferencedCodeAttribute'.
  'RequiresUnreferencedCodeAttribute' annotations must match across all interface implementations or overrides.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(88,16): error IL2046:
  Member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.ToString(Object, Type)' with 'RequiresUnreferencedCodeAttribute' implements interface member 'Uno.Extensions.Serialization.ISerializer.ToString(Object, Type)' without 'RequiresUnreferencedCodeAttribute'.
  'RequiresUnreferencedCodeAttribute' annotations must match across all interface implementations or overrides.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(107,17): error IL2046:
  Member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.FromString(String, Type)' with 'RequiresUnreferencedCodeAttribute' implements interface member 'Uno.Extensions.Serialization.ISerializer.FromString(String, Type)' without 'RequiresUnreferencedCodeAttribute'.
  'RequiresUnreferencedCodeAttribute' annotations must match across all interface implementations or overrides.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(120,14): error IL2046:
  Member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.FromString(String, Type)' with 'RequiresUnreferencedCodeAttribute' implements interface member 'Uno.Extensions.Serialization.ISerializer.FromString(String, Type)' without 'RequiresUnreferencedCodeAttribute'.
  'RequiresUnreferencedCodeAttribute' annotations must match across all interface implementations or overrides.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(43,17): error IL2046:
  Member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.FromStream(Stream, Type)' with 'RequiresUnreferencedCodeAttribute' implements interface member 'Uno.Extensions.Serialization.ISerializer.FromStream(Stream, Type)' without 'RequiresUnreferencedCodeAttribute'.
  'RequiresUnreferencedCodeAttribute' annotations must match across all interface implementations or overrides.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(120,14): error IL2046:
  Member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.FromStream(Stream, Type)' with 'RequiresUnreferencedCodeAttribute' implements interface member 'Uno.Extensions.Serialization.ISerializer.FromStream(Stream, Type)' without 'RequiresUnreferencedCodeAttribute'.
  'RequiresUnreferencedCodeAttribute' annotations must match across all interface implementations or overrides.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(62,14): error IL2046:
  Member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.ToStream(Stream, Object, Type)' with 'RequiresUnreferencedCodeAttribute' implements interface member 'Uno.Extensions.Serialization.ISerializer.ToStream(Stream, Object, Type)' without 'RequiresUnreferencedCodeAttribute'.
  'RequiresUnreferencedCodeAttribute' annotations must match across all interface implementations or overrides.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(120,14): error IL2046:
  Member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.ToStream(Stream, Object, Type)' with 'RequiresUnreferencedCodeAttribute' implements interface member 'Uno.Extensions.Serialization.ISerializer.ToStream(Stream, Object, Type)' without 'RequiresUnreferencedCodeAttribute'.
  'RequiresUnreferencedCodeAttribute' annotations must match across all interface implementations or overrides.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(146,10): error IL2026:
  Using member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.FromStream(Stream, Type)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code.
  From JsonDeserializer: JSON serialization and deserialization might require types that cannot be statically analyzed and might need runtime code generation.
  Use System.Text.Json source generation for native AOT applications.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(157,10): error IL2026:
  Using member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.ToString(Object, Type)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code.
  From JsonDeserializer: JSON serialization and deserialization might require types that cannot be statically analyzed and might need runtime code generation.
  Use System.Text.Json source generation for native AOT applications.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(140,10): error IL2026:
  Using member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.FromString(String, Type)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code.
  From JsonDeserializer: JSON serialization and deserialization might require types that cannot be statically analyzed and might need runtime code generation.
  Use System.Text.Json source generation for native AOT applications.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(168,3): error IL2026:
  Using member 'Uno.Extensions.Serialization.SystemTextJsonSerializer.ToStream(Stream, Object, Type)' which has 'RequiresUnreferencedCodeAttribute' can break functionality when trimming application code.
  From JsonDeserializer: JSON serialization and deserialization might require types that cannot be statically analyzed and might need runtime code generation.
  Use System.Text.Json source generation for native AOT applications.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(46,89): error IL3050:
  Using member 'System.Text.Json.JsonSerializer.Deserialize(Stream, Type, JsonSerializerOptions)' which has 'RequiresDynamicCodeAttribute' can break functionality when AOT compiling.
  JSON serialization and deserialization might require types that cannot be statically analyzed and might need runtime code generation.
  Use System.Text.Json source generation for native AOT applications.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(71,4): error IL3050:
  Using member 'System.Text.Json.JsonSerializer.Serialize(Stream, Object, Type, JsonSerializerOptions)' which has 'RequiresDynamicCodeAttribute' can break functionality when AOT compiling.
  JSON serialization and deserialization might require types that cannot be statically analyzed and might need runtime code generation.
  Use System.Text.Json source generation for native AOT applications.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(91,85): error IL3050:
  Using member 'System.Text.Json.JsonSerializer.Serialize(Object, Type, JsonSerializerOptions)' which has 'RequiresDynamicCodeAttribute' can break functionality when AOT compiling.
  JSON serialization and deserialization might require types that cannot be statically analyzed and might need runtime code generation.
  Use System.Text.Json source generation for native AOT applications.
src/Uno.Extensions.Serialization/SystemTextJsonSerializer.cs(110,89): error IL3050:
  Using member 'System.Text.Json.JsonSerializer.Deserialize(String, Type, JsonSerializerOptions)' which has 'RequiresDynamicCodeAttribute' can break functionality when AOT compiling.
  JSON serialization and deserialization might require types that cannot be statically analyzed and might need runtime code generation.
  Use System.Text.Json source generation for native AOT applications.

Suppress the above warnings. The foundation logic in
SystemTextJsonSerializer.cs has been reworked to check
JsonSerializer.IsReflectionEnabledByDefault, which in turn
should mirror the $(JsonSerializerIsReflectionEnabledByDefault)
MSBuild property. This allows us to mirror System.Text.Json default
behavior, attempting Reflection use when
JsonSerializer.IsReflectionEnabledByDefault is true, otherwise
throwing an InvalidOperationException stating how to address the
problem:

Reflection-based serialization has been disabled for this application.
Use the IServiceCollection.AddJsonTypeInfoResolvers() or IHostBuilder.UseSerializationResolvers() extension methods to enable JSON deserialization for type `Example`.

Which brings us to issue #2908: when a Uno app uses
.UseAuthentication() when
$(JsonSerializerIsReflectionEnabledByDefault)=false, the app
may crash with:

at System.Text.Json.ThrowHelper.ThrowInvalidOperationException_JsonSerializerIsReflectionDisabled()
at System.Text.Json.JsonSerializerOptions.ConfigureForJsonSerializer()
at System.Text.Json.JsonSerializerOptions.MakeReadOnly(Boolean populateMissingResolver)
at System.Text.Json.JsonSerializer.GetTypeInfo(JsonSerializerOptions options, Type inputType)
at System.Text.Json.JsonSerializer.Serialize(Object value, Type inputType, JsonSerializerOptions options)
at Uno.Extensions.Serialization.SystemTextJsonSerializer.ToString(Object value, Type valueType)
at Uno.Extensions.Serialization.SerializerExtensions.ToString[String](ISerializer serializer, String value)
at Uno.Extensions.Storage.KeyValueStorage.ApplicationDataKeyValueStorage.Serialize[String](String value)
at Uno.Extensions.Storage.KeyValueStorage.ApplicationDataKeyValueStorage.<GetObjectValue>d__35`1[[System.String, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
at Uno.Extensions.Storage.KeyValueStorage.ApplicationDataKeyValueStorage.<InternalSetAsync>d__36`1[[System.String, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
at Uno.Extensions.Storage.KeyValueStorage.BaseKeyValueStorageWithCaching.<SetAsync>d__21`1[[System.String, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
at Uno.Extensions.Authentication.TokenCache.SaveAsync(String provider, IDictionary`2 tokens, CancellationToken cancellation)
at Uno.Extensions.Authentication.AuthenticationService.LoginAsync(IDispatcher dispatcher, IDictionary`2 credentials, String provider, Nullable`1 cancellationToken)
at UnoApp140.Presentation.LoginModel.Login(CancellationToken token) in X:\src\TestApps\UnoApp140\UnoApp140\Presentation\LoginModel.cs:line 12

How do we fix this? Based on the above, we need a
.UseSerialization(…) invocation which contains the
IJsonTypeInfoResolver values which are needed to make the above work.

The problem: what types need to be supported? This is "fun" because
of generics: .AddKeyedStorage() registers an IKeyValueStorage
implementation, and TokenCache uses IKeyValueStorage.SetAsync<T>().
Uno.Extensions.Storage cannot know which types that TokenCache
will use; it needs to be told.

Update Uno.Extensions.Authentication to have a new internal
TokenCacheContext type which holds the JsonTypeInfo<T> values
that it will use with IKeyValueStorage.SetAsync<T>(), and update
.UseAuthentication() to call
.AddJsonSerialization(TokenCacheContext.Default), so that the
required types are available at runtime. This fixes #2908.

TODO: Uno.Extensions.Configuration uses Uno.Extensions.Serialization,
but the types to support are not statically knowable. For example,
WritableOptions<T> needs an ISerializer<Dictionary<string, T>>,
but as T is provided by a .Section<TSettingsOptions>(), which is
part of the app, there is no way for Uno.Extensions.Configuration
to provide the required JsonTypeInfo<TSettingsOptions>.

A thought is to provide a .Section<TSettingsOptions>() overload
which has a JsonTypeInfo<TSettingsOptions> parameter, but this use
case also overlaps with issue #3001.

[jonpryor]

Had a chat with @kazo0. Summary:

• Agree that we want build-time warnings to direct customers to new APIs for trimming support.
• Instead of a new family of .UseJsonSerializationResolvers() extension methods, override the existing .UseSerialization() extension methods.
• Update Uno.Extensions.Storage.UI to use the new .UseSerialization() extension method overload to actually fix [.NET10] System.InvalidOperationException: JsonSerializerIsReflectionDisabled thrown with net10 and MSAL/OIDC on WASM #2908.

[github-actions]

Azure Static Web Apps: Your stage site is ready! Visit it here: https://delightful-moss-0c5b8040f-2996.eastus2.azurestaticapps.net

[agneszitte]

/unobot prepare-release --commit-message-pattern "ci: Set version to '{0}'"

[unodevops]

The release branch release/stable/7.1 has been created from ce51198 and the PR #3014 has been created for the version bump.