Strings containing a DateTime formatted value are parsed and converted to server's time zone even when Newtonsoft JSON serializer is used and date parsing is disabled when using a Cosmos DB trigger

[mickvikt]

Description

Context of our problem:

• We have a Cosmos DB triggered function
• We want to retain the ability to use fluid JSON schema, so we're specifying JObject to be used by Cosmos DB trigger instead of a POCO type
• We have configured Newtonsoft JSON as our serializer
• We have explicitly disabled date parsing specifying DateParseHandling.None in JsonSerializerSettings
• We have dates stored as strings containing a date time in a local time zone and we need to retain original time zones

The problem:

Strings containing dates are converted to server's time zone.

Steps to reproduce

1. Create a new Cosmos DB triggered Azure function, accepting an IReadOnlyList<JObject>:

public class MyCosmosDbTrigger
{
    private readonly ILogger _logger;

    public MyCosmosDbTrigger(ILoggerFactory loggerFactory)
    {
        _logger = loggerFactory.CreateLogger<MyCosmosDbTrigger>();
    }

    [Function("MyCosmosDbTrigger")]
    public void Run([CosmosDBTrigger(
            databaseName: "MyDatabase",
            containerName: "MyContainer",
            Connection = "CosmosDbConnectionString",
            LeaseContainerName = "leases",
            CreateLeaseContainerIfNotExists = true)] 
        IReadOnlyList<JObject> input,
        FunctionContext context)
    {
        foreach (var document in input)
        {
            this._logger.LogInformation(document.ToString());
        }
    }
}

2. Create database MyDatabase and a new container MyContainer in your Cosmos DB emulator
3. Set CosmosDbConnectionString in local.settings.json to your Cosmos DB emulator connection string
4. Add nuget package Microsoft.Azure.Core.NewtonsoftJson
5. Configure functions worker defaults in Program.cs to use Newtonsoft JSON as a serializer and set DateParseHandling to DateParseHandling.None

var host = new HostBuilder()
    .ConfigureFunctionsWorkerDefaults(builder =>
    {
        builder.Services.Configure<WorkerOptions>(options =>
        {
            var settings = NewtonsoftJsonObjectSerializer.CreateJsonSerializerSettings();
            settings.DateParseHandling = DateParseHandling.None;
            options.Serializer = new NewtonsoftJsonObjectSerializer(settings);
        });
    })
    .Build();

host.Run();

6. Run the function
7. Create a new document containing data provided below in container MyContainer of the MyDatabase database of your Cosmos DB emulator to trigger function execution:

{
    "id": "1",
    "dateAsString": "2024-04-29T11:35:00+08:00"
}

8. Observe in the log output that date is converted to server's time zone. Sample log output:

[2024-05-06T13:06:45.943Z] Executing 'Functions.MyCosmosDbTrigger' (Reason='New changes on container MyContainer at 2024-05-06T13:06:45.9175858Z', Id=c36d2261-fd79-43be-9128-81940a4e2598)
[2024-05-06T13:06:46.041Z] {
[2024-05-06T13:06:46.043Z]   "id": "1",
[2024-05-06T13:06:46.043Z]   "dateAsString": "2024-04-29T06:35:00+03:00",
[2024-05-06T13:06:46.044Z]   "_rid": "NNRYAJ5akvwDAAAAAAAAAA==",
[2024-05-06T13:06:46.045Z]   "_self": "dbs/NNRYAA==/colls/NNRYAJ5akvw=/docs/NNRYAJ5akvwDAAAAAAAAAA==/",
[2024-05-06T13:06:46.045Z]   "_etag": "\"00000000-0000-0000-9fb6-3d892aca01da\"",
[2024-05-06T13:06:46.046Z]   "_attachments": "attachments/",
[2024-05-06T13:06:46.047Z]   "_ts": 1715000802,
[2024-05-06T13:06:46.047Z]   "_lsn": 98
[2024-05-06T13:06:46.048Z] }
[2024-05-06T13:06:46.060Z] Executed 'Functions.MyCosmosDbTrigger' (Succeeded, Id=c36d2261-fd79-43be-9128-81940a4e2598, Duration=134ms)

[SilvijaC]

I have the same issue

[mickvikt]

Is there any developments on this problem? This is the only reason keeping us from migrating to isolated model!