SystemTextJsonSerializer: Adds Default STJ Serializer

[kundadebdatta]

Pull Request Template

Description

This PR adds a Default System.Text.JSON Implementation for CosmosLinqSerializer. This default serializer can be used along with the CosmosClientOptions to set the runtime serializer. Please take a look at the example below for usage:

        CosmosClientOptions clientOptions = new CosmosClientOptions()
        {
            Serializer = new CosmosDefaultSystemTextJsonSerializer(
                new System.Text.Json.JsonSerializerOptions())
        };

Note that this is just a default implementation which handles the basic scenarios. Any JsonSerializerOptions passed in here may not going to be reflected in SerializeMemberName().

To handle special cases, please create a custom serializer which inherits from the CosmosDefaultSystemTextJsonSerializer and overrides the SerializeMemberName() method to add any special handling.

Below is an example of a custom serializer, which is inherits the CosmosDefaultSystemTextJsonSerializer to cover the special handling for camel case naming property.

    public class CustomSystemTextJsonSerializer : CosmosDefaultSystemTextJsonSerializer
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="CustomSystemTextJsonSerializer "/> class.
        /// </summary>
        /// <param name="jsonSerializerOptions"></param>
        public CustomSystemTextJsonSerializer (JsonSerializerOptions jsonSerializerOptions)
            : base(jsonSerializerOptions)
        {
        }

        /// <inheritdoc/>
        public override string SerializeMemberName(MemberInfo memberInfo)
        {
            System.Text.Json.Serialization.JsonExtensionDataAttribute jsonExtensionDataAttribute =
                memberInfo.GetCustomAttribute<System.Text.Json.Serialization.JsonExtensionDataAttribute>(true);
            if (jsonExtensionDataAttribute != null)
            {
                return null;
            }

            JsonPropertyNameAttribute jsonPropertyNameAttribute = memberInfo.GetCustomAttribute<JsonPropertyNameAttribute>(true);
            if (!string.IsNullOrEmpty(jsonPropertyNameAttribute?.Name))
            {
                return jsonPropertyNameAttribute.Name;
            }

            return System.Text.Json.JsonNamingPolicy.CamelCase.ConvertName(memberInfo.Name);
        }
    }

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

Closing issues

To automatically close an issue: closes #4330

[adityasa]

🕐

[adityasa]

                "Select number -> Min w/ mapping", b => getQuery(b)

Nit - please include serializer name here too.

---

Refers to: Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.EmulatorTests/Linq/LinqAggregateCustomSerializationBaseline.cs:154 in 683ca13. [](commit_id = 683ca13, deletion_comment = False)

[adityasa]

[Maya-Painter]

I've updated the STJ sample code and made some improvements to this function in this PR #4420. Could you update this function to look like this - https://github.com/Azure/azure-cosmos-dotnet-v3/blob/master/Microsoft.Azure.Cosmos.Samples/Usage/SystemTextJson/CosmosSystemTextJsonSerializer.cs ? Thanks!

[kundadebdatta]

Thanks @Maya-Painter. We are trying to gather some feedback from the .NET team on this. I will take your changes as well, and update the PR.

[eiriktsarpalis]

The JsonTypeInfo/JsonPropertyInfo types contain authoritative information on the JSON contract used by a particular type/property. See https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/custom-contracts for more details.

[kirankumarkolli]

Thank you @eiriktsarpalis !

[kundadebdatta]

Thanks for your suggestion @eiriktsarpalis! Looks like, these (JsonSerializerOptions.TryGetTypeInfo, custom contracts) are applicable for the latest versions of the System.Text.JSON package, and it's not available in 4.6.0.

In order to use the System.Text.Json (STJ) serializer, we currently depend on the Azure.Core nuget package (specifically for this class JsonObjectSerializer). The current version of Azure.Core library, referred in our v3 .NET SDK is 1.19.0, which is quite old. This internally uses System.Text.Json version 4.6.0.

I am planning to keep this suggestion as follow-up task 4479 to upgrade the Azure.Core library to the latest. Even the latest version of Azure.Core 1.39.0 library uses the STJ version 4.7.2.

[kirankumarkolli]

How about only make this type public once is fully addressed?

[bartelink]

The fact that Azure.Core 'uses' (gets by with) an old version does not of itself mean that this lib can't take a dependency on a higher version. I'd ask, what version would simplify and/or significantly improve perf here? Then validate the answer by lookign at package download counts at https://www.nuget.org/packages/system.text.json.
For instance 6.0.1 has a net6.0 variant and seems to be in popular use, and is only 18 months newer - it's not like STJ is known to be a pain to upgrade.
But of course, I'm just being a devil's advocate; there's lots of silent votes for the status quo!
Hopefully there will be a security reason along to trigger a forced upgrade in due course ;)
The other benefit of taking a higher dep is that perf in general has been on an upward trajectory, and the perceived experience of the SDK would hence also improve for people that don't explicitly pin latest in their apps

[adityasa]

[kirankumarkolli]

Is canSeek is not really required right?

[bartelink]

its great that I don't need to care as this will be an impl detail deep in a library but this formatting/named params is way overkill and makes it look like some really exciting stuff is going on, which there isnt
is the intention to disambiguate from some adjacent overload?
in general I'd be nice if this code was scannable so people can compare their impls quickly before deleting them in favor of this one