Add DateOnly and TimeOnly support to System.Text.Json #69160

eiriktsarpalis · 2022-05-10T21:07:55Z

ghost · 2022-05-10T21:07:59Z

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ghost · 2022-05-10T21:08:07Z

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Issue Details

Fix #53539.

Author:	eiriktsarpalis
Assignees:	eiriktsarpalis
Labels:	`area-System.Text.Json`, `new-api-needs-documentation`
Milestone:	7.0.0

piekstra · 2022-05-11T16:38:53Z

@eiriktsarpalis will this address serialization failures when DateOnly is used as a key in a dictionary on an object? I've added a custom DateOnly JsonConverter that works well when there are DateOnly properties on an object, but fails for some reason when one of the properties is Dictionary<DateOnly, decimal>

eiriktsarpalis · 2022-05-11T18:31:08Z

@eiriktsarpalis will this address serialization failures when DateOnly is used as a key in a dictionary on an object? I've added a custom DateOnly JsonConverter that works well when there are DateOnly properties on an object, but fails for some reason when one of the properties is Dictionary<DateOnly, decimal>

Yes, the DateOnly converter comes with support for dictionary keys. In the meantime, if you are running .NET 6 it should be possible to add support for key serialization in your custom converter by overriding the WriteAsPropertyName/ReadAsPropertyName methods.

piekstra · 2022-05-11T18:40:59Z

Yes, the DateOnly converter comes with support for dictionary keys. In the meantime, if you are running .NET 6 it should be possible to add support for key serialization in your custom converter by overriding the WriteAsPropertyName/ReadAsPropertyName methods.

Thank you! That was the piece I was missing. Works great now 😄

src/libraries/System.Text.Json/ref/System.Text.Json.csproj

...es/System.Text.Json/src/System/Text/Json/Serialization/Converters/Value/DateOnlyConverter.cs

...es/System.Text.Json/src/System/Text/Json/Serialization/Converters/Value/TimeOnlyConverter.cs

...ries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/RealWorldContextTests.cs

...es/System.Text.Json/src/System/Text/Json/Serialization/Converters/Value/DateOnlyConverter.cs

.../System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/SerializationContextTests.cs

...es/System.Text.Json/src/System/Text/Json/Serialization/Converters/Value/TimeOnlyConverter.cs

...ries/System.Text.Json/src/System/Text/Json/Serialization/JsonSerializerOptions.Converters.cs

src/libraries/System.Text.Json/src/System/Text/Json/ThrowHelper.cs

src/libraries/System.Text.Json/gen/JsonSourceGenerator.Parser.cs

…r.cs Co-authored-by: Layomi Akinrinade <[email protected]>

...tem.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonMetadataServices.Converters.cs

src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/ContextClasses.cs

src/libraries/System.Text.Json/src/System/Text/Json/ThrowHelper.cs

stephentoub · 2022-06-23T16:53:35Z

src/libraries/System.Text.Json/src/System/Text/Json/JsonHelpers.Date.cs

            public int Year;
            public int Month;
            public int Day;
+            public bool IsCalendarDateOnly;


I don't know if it would help with #69447 (comment), but defining this field here will increase the size of this struct from 40 bytes to 48 bytes on 64-bit. If you instead move this field to the end, the size should stay at 40.

Not seeing a difference in benchmarks when I rearrange the fields, but I could try pushing the change and see if it registers in the performance infrastructure.

Add DateOnly and TimeOnly support to System.Text.Json

1f1f413

eiriktsarpalis added this to the 7.0.0 milestone May 10, 2022

eiriktsarpalis requested review from krwq and layomia May 10, 2022 21:07

eiriktsarpalis self-assigned this May 10, 2022

ghost added area-System.Text.Json new-api-needs-documentation labels May 10, 2022

eiriktsarpalis requested a review from tarekgh May 11, 2022 19:00