How to make sure that NJsonSchema only includes required fields?

Question

I'm using NJsonSchema v2.6 for generating the JSON Schema for the following class:

[DataContract(Name = "Message", Namespace = "")]
public class AMessageModel
{
    [DataMember]
    internal Guid MessageId { get; set; }

    internal DateTime MessageDate { get; set; }
}

[DataContract(Name = "Message", Namespace = "")]
public class AddUserMessage : AMessageModel
{
    [DataMember]
    public string AccountName { get; set; }

    [DataMember]
    public string FistName { get; set; }

    [Range(2, 5)]
    [DataMember]
    public string LastName { get; set; }

    [DataMember]
    public string Email { get; set; }

    [DataMember]
    public string Password { get; set; }
}

The generated JSON Schema:

        {
          "$schema": "http://json-schema.org/draft-04/schema#",
          "type": "object",
          "typeName": "AddFitnessHubAccountMessage",
          "additionalProperties": false,
          "properties": {
            "AccountName": {
              "type": [
                "null",
                "string"
              ]
            },
            "FistName": {
              "type": [
                "null",
                "string"
              ]
            },
            "LastName": {
              "type": [
                "null",
                "string"
              ]
            },
            "Email": {
              "type": [
                "null",
                "string"
              ]
            },
            "Password": {
              "type": [
                "null",
                "string"
              ]
            }
          },
          "allOf": [
            {
              "type": "object",
              "typeName": "AMessageModel",
              "additionalProperties": false,
              "properties": {
                "MessageId": {
                  "type": "string",
                  "format": "guid"
                },
                "MessageDate": {
                  "type": "string",
                  "format": "date-time"
                }
              }
            }
          ]
        }

Even though the MessageDate property is not marked as a DataMember, it is always included in the schema, also the generated schema includes two schema paths when it should only include one, it seems that the parser is not flattening the properties.

UPDATE

This fixes the issue with multiple schema paths being created

new JsonSchemaGeneratorSettings
{
    FlattenInheritanceHierarchy = true
}

GitHub Issue: https://github.com/NJsonSchema/NJsonSchema/issues/53

Answer 1

I'm the author of the library NJsonSchema.

Ignored properties

There was a bug in the library and now (v2.7+) property ignore works as follows:

A property is ignored when either

1. The property is marked with the JsonIgnoreAttribute property
2. The class has an DataContractAttribute attribute and the property has no DataMemberAttribute and no JsonPropertyAttribute

https://github.com/NJsonSchema/NJsonSchema/wiki/JsonSchemaGenerator

Flatten inheritance hierarchy

As you already found out, you can flatten the inheritance hierarchy via the FlattenInheritanceHierarchy setting...

The library is mainly used for code generation, and thus the inheritance is usually needed.