https://github.com/aviationexam/json-converter-source-generator

Source generated polymorphic JSON converters
https://github.com/aviationexam/json-converter-source-generator

csharp-sourcegenerator dotnet enum-serialization json polymorphic-types system-text-json

Last synced: 5 months ago
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Source generated polymorphic JSON converters

• Host: GitHub
• URL: https://github.com/aviationexam/json-converter-source-generator
• Owner: aviationexam
• License: mit
• Created: 2023-09-25T19:44:29.000Z (over 1 year ago)
• Default Branch: main
• Last Pushed: 2024-11-05T15:12:03.000Z (5 months ago)
• Last Synced: 2024-11-05T16:29:42.308Z (5 months ago)
• Topics: csharp-sourcegenerator, dotnet, enum-serialization, json, polymorphic-types, system-text-json
• Language: C#
• Homepage:
• Size: 296 KB
• Stars: 4
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE.md

Awesome Lists containing this project

• RSCG_Examples - https://github.com/aviationexam/json-converter-source-generator
• csharp-source-generators - GeneratedJsonConverters -   - generate json converters for polymorph contracts and string based enum serialization. (Source Generators / Serialization)

README

        
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# Aviationexam.GeneratedJsonConverters.SourceGenerator

Motivation for this library are polymorphic contracts with discriminator property not present as first property.

i.e. this JSON

```json

{

    "baseProperty": 1,

    "$type": 2,

    "anotherLeafProperty": 2

}

```

is deserialized correctly into `AnotherLeafContract` using this library.

And string based enum serialization.

## Install

```xml

    

```

## How to use library

```xml

    

    public

    NamespaceOf.My.Json.Serializer.Context

    MyJsonSerializerContext

    

    BackingType

    

    UseBackingType|UseEnumName

```

```cs

// file=contracts.cs

using Aviationexam.GeneratedJsonConverters.Attributes;

[JsonPolymorphic] // notice, that attributes are from `Aviationexam.GeneratedJsonConverters.Attributes` namespace, not `System.Text.Json.Serialization`

[JsonDerivedType(typeof(LeafContract), typeDiscriminator: nameof(LeafContract))]

[JsonDerivedType(typeof(AnotherLeafContract), typeDiscriminator: 2)]

[JsonDerivedType(typeDiscriminator: nameof(GenericLeafContract))]

public abstract class BaseContract

{

    public int BaseProperty { get; set; }

}

public sealed class LeafContract : BaseContract

{

    public int LeafProperty { get; set; }

}

public sealed class AnotherLeafContract : BaseContract

{

    public int AnotherLeafProperty { get; set; }

}

public sealed class GenericLeafContract : BaseContract

{

    public int Property { get; set; }

}

[EnumJsonConverter] // this use project defined configuration

public enum EMyEnum

{

    [EnumMember(Value = "C")]

    A,

    [EnumMember(Value = "D")]

    B,

}

[EnumJsonConverter(

    SerializationStrategy = EnumSerializationStrategy.FirstEnumName,

    DeserializationStrategy = EnumDeserializationStrategy.UseEnumName

)]

public enum EMyEnumWithExplicitConfiguration

{

    [EnumMember(Value = "C")]

    A,

    [EnumMember(Value = "D")]

    B,

}

[DisableEnumJsonConverter]

public enum EMyIgnoredEnum

{

    C,

    D,

}

// file=MyJsonSerializerContext.cs

using System.Text.Json.Serialization;

[JsonSerializable(typeof(BaseContract))] // this line is neccesary, generator searches for JsonSerializableAttribute with argument type decorated by JsonPolymorphicAttribute

[JsonSerializable(typeof(LeafContract))] // notice, it's necessary to specify leaf types

[JsonSerializable(typeof(AnotherLeafContract))]

[JsonSerializable(typeof(GenericLeafContract))]

[JsonSerializable(typeof(EMyEnum))] // only necessary for not referenced enums from other contracts

[JsonSerializable(typeof(EMyEnumWithExplicitConfiguration))]

public partial class MyJsonSerializerContext : JsonSerializerContext

{

    static MyJsonSerializerContext()

    {

        // register generated converters to options

        UsePolymorphicConverters(s_defaultOptions.Converters);

        UseEnumConverters(s_defaultOptions.Converters);

#if NET8_0_OR_GREATER

        Default = new MyJsonSerializerContext(new System.Text.Json.JsonSerializerOptions(s_defaultOptions));

#endif

    }

}

```