DynamicJsonPropertyNamingPolicy

A System.Text.Json.JsonNamingPolicy that reacts to request headers.

Usage

Based on the value of the json-naming-strategy request header, this package will determine what type of serialization method to follow when one of the following is used:

1. camel for camelCase
2. pascal for PascalCase
3. snake for snake_case

If nothing is sent in the header, it will default to snake_case for compatibility with the systems it was originally built for.

As an InputFormatter

This method will allow your ASP.NET controllers to correctly deserialize incoming JSON following the json-naming-strategy.

builder.Services.AddControllers(o =>
{
    o.InputFormatters.Insert(0, new DynamicSystemTextJsonInputFormatter());
});

Which would then allow you to receive a request body of:

{
    "time_stamp": "2021-09-16T22:05:29.846Z"
}

and correctly deserialize it into:

public record WeatherForecast
{
    public DateTime TimeStamp { get; set; }
}

In JsonSerializerOptions

If you just want to use JsonSerializerOptions that apply the correct property naming use the following:

return new JsonResult(result, HttpContext.GetJsonSerializerOptions());

Otherwise, you can just reference the JsonNamingPolicy to add additional options:

var namingPolicy = HttpContext.GetJsonNamingPolicy();
return new JsonResult(result, new JsonSerializerOptions
{
    PropertyNamingPolicy = namingPolicy,
    NumberHandling = JsonNumberHandling.AllowReadingFromString
});

This allows you to send a response back to the requestor that will respect their request for a specific serialization strategy.

Example

You can see usage as an InputFormatter in Program.cs and as JsonSerializerOptions in WeatherForecastController.cs.

Additionally, you can run the Sample project with:

dotnet run

And then load https://localhost:5001/swagger to try out some requests. Within the SwaggerUI, you can specify the json-naming-strategy header to see the differences.

Contributing

Please see CONTRIBUTING.md for details on how to contribute to the project.