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Résolveur de nom personnalisé JSON .NET pour les sous-propriétés

Ce que vous pouvez faire est, pour la propriété en question, de créer un personnalisé JsonConverter qui sérialise la valeur de la propriété en question en utilisant un autre JsonSerializer créé avec un résolveur de contrat différent, comme ceci :

public class AlternateContractResolverConverter : JsonConverter
{
    [ThreadStatic]
    static Stack<Type> contractResolverTypeStack;

    static Stack<Type> ContractResolverTypeStack { get { return contractResolverTypeStack = (contractResolverTypeStack ?? new Stack<Type>()); } }

    readonly IContractResolver resolver;

    JsonSerializerSettings ExtractAndOverrideSettings(JsonSerializer serializer)
    {
        var settings = serializer.ExtractSettings();
        settings.ContractResolver = resolver;
        settings.CheckAdditionalContent = false;
        if (settings.PreserveReferencesHandling != PreserveReferencesHandling.None)
        {
            // Log an error throw an exception?
            Debug.WriteLine(string.Format("PreserveReferencesHandling.{0} not supported", serializer.PreserveReferencesHandling));
        }
        return settings;
    }

    public AlternateContractResolverConverter(Type resolverType)
    {
        if (resolverType == null)
            throw new ArgumentNullException("resolverType");
        resolver = (IContractResolver)Activator.CreateInstance(resolverType);
        if (resolver == null)
            throw new ArgumentNullException(string.Format("Resolver type {0} not found", resolverType));
    }

    public override bool CanRead { get { return ContractResolverTypeStack.Count == 0 || ContractResolverTypeStack.Peek() != resolver.GetType(); } }
    public override bool CanWrite { get { return ContractResolverTypeStack.Count == 0 || ContractResolverTypeStack.Peek() != resolver.GetType(); } }

    public override bool CanConvert(Type objectType)
    {
        throw new NotImplementedException("This contract resolver is intended to be applied directly with [JsonConverter(typeof(AlternateContractResolverConverter), typeof(SomeContractResolver))] or [JsonProperty(ItemConverterType = typeof(AlternateContractResolverConverter), ItemConverterParameters = ...)]");
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        using (ContractResolverTypeStack.PushUsing(resolver.GetType()))
            return JsonSerializer.CreateDefault(ExtractAndOverrideSettings(serializer)).Deserialize(reader, objectType);
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        using (ContractResolverTypeStack.PushUsing(resolver.GetType()))
            JsonSerializer.CreateDefault(ExtractAndOverrideSettings(serializer)).Serialize(writer, value);
    }
}

internal static class JsonSerializerExtensions
{
    public static JsonSerializerSettings ExtractSettings(this JsonSerializer serializer)
    {
        // There is no built-in API to extract the settings from a JsonSerializer back into JsonSerializerSettings,
        // so we have to fake it here.
        if (serializer == null)
            throw new ArgumentNullException("serializer");
        var settings = new JsonSerializerSettings
        {
            CheckAdditionalContent = serializer.CheckAdditionalContent,
            ConstructorHandling = serializer.ConstructorHandling,
            ContractResolver = serializer.ContractResolver,
            Converters = serializer.Converters,
            Context = serializer.Context,
            Culture = serializer.Culture,
            DateFormatHandling = serializer.DateFormatHandling,
            DateFormatString = serializer.DateFormatString,
            DateParseHandling = serializer.DateParseHandling,
            DateTimeZoneHandling = serializer.DateTimeZoneHandling,
            DefaultValueHandling = serializer.DefaultValueHandling,
            EqualityComparer = serializer.EqualityComparer,
            // No Get access to the error event, so it cannot be copied.
            // Error = += serializer.Error
            FloatFormatHandling = serializer.FloatFormatHandling,
            FloatParseHandling = serializer.FloatParseHandling,
            Formatting = serializer.Formatting,
            MaxDepth = serializer.MaxDepth,
            MetadataPropertyHandling = serializer.MetadataPropertyHandling,
            MissingMemberHandling = serializer.MissingMemberHandling,
            NullValueHandling = serializer.NullValueHandling,
            ObjectCreationHandling = serializer.ObjectCreationHandling,
            ReferenceLoopHandling = serializer.ReferenceLoopHandling,
            // Copying the reference resolver doesn't work in the default case, since the
            // actual BidirectionalDictionary<string, object> mappings are held in the 
            // JsonSerializerInternalBase.
            // See https://github.com/JamesNK/Newtonsoft.Json/blob/master/Src/Newtonsoft.Json/Serialization/DefaultReferenceResolver.cs
            ReferenceResolverProvider = () => serializer.ReferenceResolver,
            PreserveReferencesHandling = serializer.PreserveReferencesHandling,
            StringEscapeHandling = serializer.StringEscapeHandling,
            TraceWriter = serializer.TraceWriter,
            TypeNameHandling = serializer.TypeNameHandling,
            // Changes in Json.NET 10.0.1
            //TypeNameAssemblyFormat was obsoleted and replaced with TypeNameAssemblyFormatHandling in Json.NET 10.0.1
            //TypeNameAssemblyFormat = serializer.TypeNameAssemblyFormat,
            TypeNameAssemblyFormatHandling = serializer.TypeNameAssemblyFormatHandling,
            //Binder was obsoleted and replaced with SerializationBinder in Json.NET 10.0.1
            //Binder = serializer.Binder,
            SerializationBinder = serializer.SerializationBinder,
        };
        return settings;
    }
}

public static class StackExtensions
{
    public struct PushValue<T> : IDisposable
    {
        readonly Stack<T> stack;

        public PushValue(T value, Stack<T> stack)
        {
            this.stack = stack;
            stack.Push(value);
        }

        // By using a disposable struct we avoid the overhead of allocating and freeing an instance of a finalizable class.
        public void Dispose()
        {
            if (stack != null)
                stack.Pop();
        }
    }

    public static PushValue<T> PushUsing<T>(this Stack<T> stack, T value)
    {
        if (stack == null)
            throw new ArgumentNullException();
        return new PushValue<T>(value, stack);
    }
}

Alors utilisez-le comme ceci :

public class RootObject
{
    public string Name { get; set; }
    public DateTime DateCreated { get; set; }

    [JsonProperty(NamingStrategyType = typeof(DefaultNamingStrategy))]
    [JsonConverter(typeof(AlternateContractResolverConverter), typeof(DefaultContractResolver))]
    public SomeDocument SomeDocument { get; set; }
}

public class SomeDocument
{
    public string MyFirstProperty { get; set; }
    public string mysecondPROPERTY { get; set; }
    public AnotherRandomSubdoc another_random_subdoc { get; set; }
}

public class AnotherRandomSubdoc
{
    public string evenmoredata { get; set; }
    public DateTime DateCreated { get; set; }
}

(Ici, je suppose que vous voulez le "SomeDocument" le nom de la propriété doit être sérialisé textuellement, même s'il n'était pas tout à fait clair d'après votre question. Pour ce faire, j'utilise JsonPropertyAttribute.NamingStrategyType à partir de Json.NET 9.0.1. Si vous utilisez une version antérieure, vous devrez définir explicitement le nom de la propriété.)

Alors le JSON résultant sera :

{
  "name": "Question 40597532",
  "dateCreated": "2016-11-14T05:00:00Z",
  "SomeDocument": {
    "MyFirstProperty": "my first property",
    "mysecondPROPERTY": "my second property",
    "another_random_subdoc": {
      "evenmoredata": "even more data",
      "DateCreated": "2016-11-14T05:00:00Z"
    }
  }
}

Notez que cette solution ne fonctionne PAS bien avec préserver les références d'objets . Si vous avez besoin qu'ils travaillent ensemble, vous devrez peut-être envisager une approche basée sur la pile similaire à celle de Json.NET sérialise par profondeur et attribut

Démo violon ici .

Incidemment, avez-vous envisagé de stocker ce JSON en tant que littéral de chaîne brute, comme dans la réponse à cette question ?