Breaking changes should mention Json.Net vs System.Text.Json

[adrianm64]

V3 uses System.Text.Json for json binding of function arguments instead of Json.Net used in V1 & V2. System.Text.Json has very different defaults, attributes and converters

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• ID: 1df5e2bd-489d-19b2-87d3-d993ebb82021
• Version Independent ID: 9e9d9ded-8f40-22be-4654-48c87f2c59e8
• Content: Azure Functions runtime versions overview
• Content Source: articles/azure-functions/functions-versions.md
• Service: azure-functions
• GitHub Login: @ggailey777
• Microsoft Alias: glenga

[DixitArora-MSFT]

Hi @adrianm64 Thanks for your feedback. We will review and update as appropriate.

[DixitArora-MSFT]

@adrianm64 In ASP.NET Core 3.0, Newtonsoft.Json types used in Authentication APIs have been replaced with System.Text.Json types. Except for the following cases, basic usage of the Authentication packages remains unaffected.

• Classes derived from the OAuth providers, such as those from aspnet-contrib.
• Advanced claim manipulation implementations.

For more information, see dotnet/aspnetcore#7105. For discussion, see dotnet/aspnetcore#7289.

This is mentioned in Public doc and more information can be found here : https://docs.microsoft.com/en-us/dotnet/core/compatibility/2.2-3.0#authentication-newtonsoftjson-types-replaced

So for now I will proceed with closure of this and If there are further questions regarding this matter, please tag me in your reply. We will gladly continue the discussion and we will reopen the issue.

[adrianm64]

@DixitArora-MSFT,

Not sure what you replied to. What I meant was that this code

public class MyClass {
    [JsonProperty("url")]
    public Uri Url {get; set;}
}

[FunctionName("TestFunction")]
public async Task TestFunction([HttpTrigger(AuthorizationLevel.Function, "post", Route = null)] MyClass myClass, ...

Works in Azure functions V2 but not in V3 because the binding in V3 uses System.Text.Json which does not recognize the JsonProperty nor deserializes System.Uri without a converter.
(which is fine but it should be mentioned as a breaking change when upgrading)