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Export Schema as JSON

EventSchemaJsonWriter serialises an IEventSchema to a JSON stream. It is included in the Hermodr.Schema package — no extra installation required.

Usage​

using Hermodr;
using System.Text.Json;

var schema = EventSchema.FromDataType<OrderPlacedData>();

var writer = new EventSchemaJsonWriter(new JsonWriterOptions { Indented = true });

await using var stream = File.OpenWrite("order-placed-schema.json");
await writer.WriteToAsync(stream, schema);

JsonWriterOptions​

Pass a System.Text.Json.JsonWriterOptions instance to control formatting:

OptionDefaultEffect
IndentedfalsePretty-print the JSON output
EncodernullCustom character encoder

Output format​

{
  "type": "order.placed",
  "version": "1.0",
  "contentType": "object",
  "description": "Raised when a customer places an order",
  "properties": {
    "OrderId": {
      "dataType": "guid",
      "required": true
    },
    "Amount": {
      "dataType": "money",
      "required": true,
      "min": 0.01,
      "max": 1000000
    },
    "Currency": {
      "dataType": "string",
      "required": true
    },
    "Notes": {
      "dataType": "string",
      "nullable": true
    }
  }
}

Writing to a string​

await using var memStream = new MemoryStream();
await writer.WriteToAsync(memStream, schema);
var json = Encoding.UTF8.GetString(memStream.ToArray());

IEventSchemaWriter interface​

EventSchemaJsonWriter implements IEventSchemaWriter:

public interface IEventSchemaWriter
{
    Task WriteToAsync(Stream stream, IEventSchema schema, CancellationToken cancellationToken = default);
}

You can register and resolve it via DI if you prefer not to instantiate it directly.