Json Converters to facilitate unit testing for Power Platform's Custom APIs

JsonConverters.cs

using Microsoft.Xrm.Sdk;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using System;

namespace MyFancyPlugins.Tests.JsonConverters;

/// <summary>
/// Allows serialization / deserialization of <see cref="Microsoft.Xrm.Sdk.EntityCollection". This type is
/// intended for unit-testing only./>
/// </summary>
public class EntityCollectionJsonConverter : JsonConverter
{
    public override bool CanConvert(Type objectType) => objectType == typeof(EntityCollection);

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        var entityCollection = value as EntityCollection;
        var jarray = new JArray();

        foreach (var entity in entityCollection.Entities)
        {
            jarray.Add(JToken.FromObject(entity, serializer));
        }

        jarray.WriteTo(writer);
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        var jarray = JArray.Load(reader);
        var entityCollection = new EntityCollection();

        foreach (var item in jarray)
        {
            entityCollection.Entities.Add(item.ToObject<Entity>(serializer));
        }

        return entityCollection;
    }
}

/// <summary>
/// Allows serialization / deserialization of <see cref="Microsoft.Xrm.Sdk.Entity". This type is
/// intended for unit-testing only./>
/// </summary>
public class EntityJsonConverter : JsonConverter
{
    public override bool CanConvert(Type typeToConvert) => typeToConvert == typeof(Entity);
    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        var jobject = JObject.Load(reader);
        var entity = new Entity();
        foreach (var property in jobject.Properties())
        {
            if (property.Value.Type == JTokenType.Array)
            {
                entity.SetAttribute(property.Name, property.Value.ToObject<EntityCollection>(serializer));
            }
            else if (property.Value.Type == JTokenType.Object && property.Value.HasValues)
            {
                entity.SetAttribute(property.Name, property.Value.ToObject<Entity>(serializer));
            }
            else if (property.Value.Type == JTokenType.Integer)
            {
                entity.SetAttribute(property.Name, property.Value.ToObject<int>(serializer));
            }
            else
            {
                entity.SetAttribute(property.Name, property.Value.ToObject<object>());
            }
        }
        return entity;
    }
    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        var entity = value as Entity;
        var jobject = new JObject();
        foreach (var attribute in entity.Attributes)
        {
            if (attribute.Value is Entity || attribute.Value is EntityCollection)
            {
                jobject.Add(attribute.Key, JToken.FromObject(attribute.Value, serializer));
            }
            else
            {
                jobject.Add(attribute.Key, JToken.FromObject(attribute.Value));
            }
        }
        jobject.WriteTo(writer);
    }
}

/// <summary>
/// Allows serialization / deserialization of <see cref="Microsoft.Xrm.Sdk.ParameterCollection". This type is
/// intended for unit-testing only./>
/// </summary>
public class ParameterCollectionJsonConverter : JsonConverter
{
    public override bool CanConvert(Type typeToConvert) => typeToConvert == typeof(ParameterCollection);

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        var jobject = JObject.Load(reader);
        var collection = new ParameterCollection();
        foreach (var property in jobject.Properties())
        {
            if (property.Value.Type == JTokenType.Array)
            {
                collection[property.Name] = property.Value.ToObject<EntityCollection>(serializer);
            }
            else if (property.Value.Type == JTokenType.Object && property.Value.HasValues)
            {
                collection[property.Name] = property.Value.ToObject<Entity>(serializer);
            }
            else if (property.Value.Type == JTokenType.Integer)
            {
                collection[property.Name] = property.Value.ToObject<int>(serializer);
            }
            else
            {
                collection[property.Name] = property.Value.ToObject<object>();
            }
        }
        return collection;
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        var collection = value as ParameterCollection;
        var jobject = new JObject();
        foreach (var attribute in collection)
        {
            if (attribute.Value is Entity || attribute.Value is EntityCollection)
            {
                jobject.Add(attribute.Key, JToken.FromObject(attribute.Value, serializer));
            }
            else
            {
                jobject.Add(attribute.Key, JToken.FromObject(attribute.Value));
            }
        }
        jobject.WriteTo(writer);
    }
}