How would you get this data in unity - json

{"country":{"code":"NZ"}}
How would you store this data in a unity class?
Something like this:
using UnityEngine;
using System;
using System.Collections;
using System.Globalization;
[Serializable]
public class GDRPClass
{
public string country;
public string code;
}
I dont think that is right for a double {} though.
Thanks

Always a very good starting point: json2csharp!
just make sure to use fields instead of properties and mark the clases [Serializable]:
[Serializable]
public class Country
{
public string code;
}
[Serializeable]
public class GDRPClass
{
public Country country;
}
You can call the classes/structs whatever you like, but the field names have to match!
In this simple case the structure is easily explained since the data types in JSON are very limited. You can see it better if you use the intended notation
{
"country" :
{
"code" : "NZ"
}
}
{ } in json always wrap a json object (= class/struct). So you already know there have to be exactly two class/struct types in your case.
you can see the first (root) type has to have one field called country. This field's type is the other class/struct's type.
this second inner type has another field called code. It's type is a string.
And that's exactly what json2csharp already spit out for us ;)
Now you can e.g. use JsonUtility.FromJson
var json = "{\"country\":{\"code\":\"NZ\"}}";
var jsonObject = JsonUtility.FromJson<GDRPClass>(json);
and later access the data using e.g.
var code = jsonObject.country.code; // = "NZ"

"country" is basically used as a key for "{"code":"NZ"}", so they're on different levels of the tree.
You could deserialize this into a Dictionary<string, CountryInfo> (but not with with the built-in JsonUtility, that doesn't do Dictionaries, so I used Json .Net instead)
Have a look:
using System;
using System.Collections.Generic;
using Newtonsoft.Json;
using UnityEngine;
public class TestDeserialize : MonoBehaviour {
[SerializeField] private string m_JsonStr = "{\"New Zealand\":{\"code\":\"NZ\"}}";
void Start() {
Dictionary<string,CountryInfo> result = JsonConvert.DeserializeObject<Dictionary<string, CountryInfo>>(m_JsonStr);
foreach (KeyValuePair<string,CountryInfo> country in result) { //Log results
Debug.LogFormat("{0}: {1}", country.Key, country.Value.code);
}
Debug.Log(JsonConvert.SerializeObject(result)); //Serializes back into its original form
}
[Serializable]
class CountryInfo {
public string code;
}
}

I use Pathfinding.Serialization.JsonFx for JSON Parsing
{\"country\":4,\"code\":\"Afghanistan\"}
This will be the jsonString with respect to your Model class
GDRPClass data = JsonReader.Deserialize<GDRPClass>JsonWriter.Serialize(jsonString));

Related

EF Core 7 can't deserialize dynamic-members in JSON column

I am trying to map my Name column to a dynamic object. This is how the raw JSON data looks (note that this is SQL-morphed from our old relational data and I am not able to generate or interact with this column via EF Core):
{ "en": "Water", "fa": "آب", "ja": "水", ... }
Just to note, available languages are stored in a separate table and thus are dynamically defined.
Through T-SQL I can perfectly interact with these objects eg
SELECT *
FROM [MyObjects]
WHERE JSON_VALUE(Name, '$.' + #languageCode) = #searchQuery
But it seems EF Core doesn't want to even deserialize these objects as whole, let alone query them.
What I get in a simple GetAll query is an empty Name. Other columns are not affected though.
I have tried so far
Using an empty class with a [JsonExtensionData] dictionary inside
Using a : DynamicObject inheritance and implementing GetDynamicMembers, TryGetMember, TrySetMember, TryCreateInstance
Directly mapping to a string dictionary.
Combining 1 & 2 and adding an indexer operator on top.
All yield the same results: an empty Name.
I have other options like going back to a junction table relational which I have many issues with, hardcoding languages which is not really intuitive and might cause problems in the future, using HasJsonConversion which basically destroys the performance on any search action... so I'm basically stuck here with this.
I think currently it's not fully supported:
You can not use dynamic operations on an expression tree like a Select statement because it needs to be translated.
JsonValue and JsonQuery requires a path to be resolved.
If you specify OwnsOne(entity = >entity.owned, owned => owned.ToJson()) and the Json could not be parsed you will get an error.
I suggest this workaround while the EF team improves the functionality.
Create a static class with static methods to be used as decoys in the expression tree. This will be mapped to the server built-in functions.
public static class DBF
{
public static string JsonValue(this string column, [NotParameterized] string path)
=> throw new NotSupportedException();
public static string JsonQuery(this string column, [NotParameterized] string path) => throw new NotSupportedException();
}
Include the database functions on your OnModelCreating method.
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.HasDbFunction(
typeof(DBF).GetMethod(nameof(DBF.JsonValue))!
).HasName("JSON_VALUE").IsBuiltIn();
modelBuilder.HasDbFunction(
typeof(DBF).GetMethod(nameof(DBF.JsonQuery))!
).HasName("JSON_QUERY").IsBuiltIn();
/// ...
modelBuilder.Entity(entity => {
//treat entity as text
entity.Property(x => x.Metadata)
.HasColumnType("varchar")
.HasMaxLength(8000);
});
}
Call them dynamically with LINQ.
var a = await _context.FileInformation
.AsNoTracking()
.Where(x => x.Metadata!.JsonValue("$.Property1") == "some value")
.Select(x => x.Metadata!.JsonValue("$.Property2"))
.ToListAsync();
You can add casts or even build anonymous types with this method.
My solution was I added a new class which has KEY and VALUE , which will represent the dictionary i needed :
public class DictionaryObject
{
public string Key { set; get; }
public string Value { set; get; }
}
and instead of having this line in the JSON class :
public Dictionary<string, string> Name { get; set; }
I changed to :
public List<DictionaryObject> Name { get; set; }
Hope it helps.

How to use ServiceStack to store POCOs to MariaDB having complex types (objects and structs) blobbed as JSON?

I've got following setup: C#, ServiceStack, MariaDB, POCOs with objects and structs, JSON.
The main question is: how to use ServiceStack to store POCOs to MariaDB having complex types (objects and structs) blobbed as JSON and still have working de/serialization of the same POCOs? All of these single tasks are supported, but I had problems when all put together mainly because of structs.
... finally during writing this I found some solution and it may look like I answered my own question, but I still would like to know the answer from more skilled people, because the solution I found is a little bit complicated, I think. Details and two subquestions arise later in the context.
Sorry for the length and for possible misinformation caused by my limited knowledge.
Simple example. This is the final working one I ended with. At the beginning there were no SomeStruct.ToString()/Parse() methods and no JsConfig settings.
using Newtonsoft.Json;
using ServiceStack;
using ServiceStack.DataAnnotations;
using ServiceStack.OrmLite;
using ServiceStack.Text;
using System.Diagnostics;
namespace Test
{
public class MainObject
{
public int Id { get; set; }
public string StringProp { get; set; }
public SomeObject ObjectProp { get; set; }
public SomeStruct StructProp { get; set; }
}
public class SomeObject
{
public string StringProp { get; set; }
}
public struct SomeStruct
{
public string StringProp { get; set; }
public override string ToString()
{
// Unable to use .ToJson() here (ServiceStack does not serialize structs).
// Unable to use ServiceStack's JSON.stringify here because it just takes ToString() => stack overflow.
// => Therefore Newtonsoft.Json used.
var serializedStruct = JsonConvert.SerializeObject(this);
return serializedStruct;
}
public static SomeStruct Parse(string json)
{
// This method behaves differently for just deserialization or when part of Save().
// Details in the text.
// After playing with different options of altering the json input I ended with just taking what comes.
// After all it is not necessary, but maybe useful in other situations.
var structItem = JsonConvert.DeserializeObject<SomeStruct>(json);
return structItem;
}
}
internal class ServiceStackMariaDbStructTest
{
private readonly MainObject _mainObject = new MainObject
{
ObjectProp = new SomeObject { StringProp = "SomeObject's String" },
StringProp = "MainObject's String",
StructProp = new SomeStruct { StringProp = "SomeStruct's String" }
};
public ServiceStackMariaDbStructTest()
{
// This one line is needed to store complex types as blobbed JSON in MariaDB.
MySqlDialect.Provider.StringSerializer = new JsonStringSerializer();
JsConfig<SomeStruct>.RawSerializeFn = someStruct => JsonConvert.SerializeObject(someStruct);
JsConfig<SomeStruct>.RawDeserializeFn = json => JsonConvert.DeserializeObject<SomeStruct>(json);
}
public void Test_Serialization()
{
try
{
var json = _mainObject.ToJson();
if (!string.IsNullOrEmpty(json))
{
var objBack = json.FromJson<MainObject>();
}
}
catch (System.Exception ex)
{
Debug.WriteLine(ex.Message);
}
}
public void Test_Save()
{
var cs = "ConnectionStringToMariaDB";
var dbf = new OrmLiteConnectionFactory(cs, MySqlDialect.Provider);
using var db = dbf.OpenDbConnection();
db.DropAndCreateTable<MainObject>();
try
{
db.Save(_mainObject);
var dbObject = db.SingleById<MainObject>(_mainObject.Id);
}
catch (System.Exception ex)
{
Debug.WriteLine(ex.Message);
}
}
}
}
What (I think) I know / have tried but at first didn't help to solve it myself:
ServiceStack stores complex types in DB as blobbed JSV by default (last paragraph of first section: https://github.com/ServiceStack/ServiceStack.OrmLite), so it is necessary to set it the way it is proposed: MySqlDialect.Provider.StringSerializer = new JsonStringSerializer(); (https://github.com/ServiceStack/ServiceStack.OrmLite#pluggable-complex-type-serializers)=> default JSV changed to JSON.
the ServiceStack's serialization does not work with structs, it is necessary to treat them special way:
a) according to https://github.com/ServiceStack/ServiceStack.Text#c-structs-and-value-types and example https://github.com/ServiceStack/ServiceStack.Text/#using-structs-to-customize-json it is necessary to implement TStruct.ToString() and static TStruct.ParseJson()/ParseJsv() methods.
b) according to https://github.com/ServiceStack/ServiceStack.Text/#typeserializer-details-jsv-format and unit tests https://github.com/ServiceStack/ServiceStack.Text/blob/master/tests/ServiceStack.Text.Tests/CustomStructTests.cs it shall be TStruct.ToString() (the same as in a) and static TStruct.Parse().
Subquestion #1: which one is the right one? For me, ParseJson() was never called, Parse() was. Documentation issue or is it used in other situation?
I implemented option b). Results:
IDbConnection.Save(_mainObject) saved the item to MariaDB. Success.
Through the saving process ToString() and Parse() were called. In Parse, incoming JSON looked this way:
"{\"StringProp\":\"SomeStruct's String\"}". Fine.
Serialization worked. Success.
Deserialization failed. I don't know the reason, but JSON incoming to Parse() was "double-escaped":
"{\\\"StringProp\\\":\\\"SomeStruct's String\\\"}"
Subquestion #2: Why the "double-escaping" in Parse on deserialization?
I tried to solve structs with JsConfig (and Newtonsoft.Json to get proper JSON):
JsConfig<SomeStruct>.SerializeFn = someStruct => JsonConvert.SerializeObject(someStruct);
JsConfig<SomeStruct>.DeSerializeFn = json => JsonConvert.DeserializeObject<SomeStruct>(json);
a) at first without ToString() and Parse() defined in the TStruct. Results:
Save failed: the json input in JsonConvert.DeserializeObject(json) that is used during Save was just type name "WinAmbPrototype.SomeStruct".
De/serialization worked.
b) then I implemented ToString() also using Newtonsoft.Json. During Save ToString() was used instead of JsConfig.SerializeFn even the JsConfig.SerializeFn was still set (maybe by design, I do not judge). Results:
Save failed: but the json input of DeserializeFn called during Save changed, now it was JSV-like "{StringProp:SomeStruct's String}", but still not deserializable as JSON.
De/serialization worked.
Then (during writing this I was still without any solution) I found JsConfig.Raw* "overrides" and tried them:
JsConfig<SomeStruct>.RawSerializeFn = someStruct => JsonConvert.SerializeObject(someStruct);
JsConfig<SomeStruct>.RawDeserializeFn = json => JsonConvert.DeserializeObject<SomeStruct>(json);
a) at first without ToString() and Parse() defined in the TStruct. Results are the same as in 2a.
b) then I implemented ToString(). Results:
BOTH WORKED. No Parse() method needed for this task.
But it is very fragile setup:
if I removed ToString(), it failed (now I understand why, default ToString produced JSON with just type name in 2a, 3a).
if I removed RawSerializeFn setting, it failed in RawDeserializeFn ("double-escaped" JSON).
Is there some simpler solution? I would be very glad if someone points me to better direction.
Acceptable would be maybe two (both of them accessible because of different circumstances):
if I am the TStruct owner: with just pure TStruct.ToString() and static TStruct.Parse() to support out of the box de/serialization and DB by ServiceStack (without different input in Parse()).
if I am a consumer of TStruct with no JSON support implemented and I am without access to its code: until now I did not find the way, if the ToString is not implemented: Save to DB did not work. Maybe would be fine to ensure JsConfig serialize functions are enough for both de/serialization and when used during saving to DB.
And the best one would be without employing other dependency (e.g. Newtonsoft.Json) to serialize structs. Maybe some JsConfig.ShallProcessStructs = true; (WARNING: just a tip, not working as of 2021-04-02) would be fine for such situations.
ServiceStack treats structs like a single scalar value type, just like most of the core BCL Value Types (e.g. TimeSpan, DateTime, etc). Overloading the Parse() and ToString() methods and Struct's Constructor let you control the serialization/deserialization of custom structs.
Docs have been corrected. Structs use Parse whilst classes use ParseJson/ParseJsv
If you want to serialize a models properties I'd suggest you use a class instead as the behavior you're looking for is that of a POCO DTO.
If you want to have structs serailized as DTOs in your RDBMS an alternative you can try is to just use JSON.NET for the complex type serialization, e.g:
public class JsonNetStringSerializer : IStringSerializer
{
public To DeserializeFromString<To>(string serializedText) =>
JsonConvert.DeserializeObject<To>(serializedText);
public object DeserializeFromString(string serializedText, Type type) =>
JsonConvert.DeserializeObject(serializedText, type);
public string SerializeToString<TFrom>(TFrom from) =>
JsonConvert.SerializeObject(from);
}
MySqlDialect.Provider.StringSerializer = new JsonNetStringSerializer();

Jackson deserialization when POJO does not match JSON structure

I have some json :
{
key: "CORE-19",
fields: { summary: "iblah" }
}
I want to pack it into a POJO that looks more like:
#JsonIgnoreProperties(ignoreUnknown=true)
public class JiraIssue
{
private String mKey;
private String mSummary;
public String getKey(){ return(mKey);}
public void setKey(String inKey){mKey = inKey;}
public String getSummary(){return(mSummary);}
public void setSummary(String summary){ mSummary = summary; }
}
So basically I don't want to create a 'Fields' object as it is a bit superfluous for my needs. However I really can't see any way in Jackson to tell it that the 'summary' property actually comes from the 'fields' property. Is this possible?
Serialization of this class is not a concern, it will only ever be used for Deserialization. I have no control over the JSON format as it is coming from an external source (and the above is just a snippet). Also I'm actually using Jackson with Jersey.
Thanks!
There is actually an open issue for this kind of structural change. There is no way as of now to do that easily with annotation only without modifying your class. What you could do instead is handle the "fields" property as a "false" property, by adding the following method:
public void setFields(Map<String, String> fields) {
setSummary(fields.get("summary"));
}
This way you "unwrap" the property yourself.
Try:
#JsonProperty("fields.summary")
private String mSummary;

How to validate double values in .Net using a custom validator?

I am developing an ASP.Net web api project and I want to validate my Server data model according to the JSON request I get from the Client side. In my Server Model Class, I have a double value and I am sending value from the Client Side as "12,14". I have written a custom validation class which is implemented by ValidationAttribute class of .Net and I am using IsValid(Object value) method to validate this user input.
So when I send my input as "12,14", .Net automatically converts this "12,14" to "1214" by thinking that "," is a group separator. But in this case, "," is not a group separator since this is a valid Double number for Norwaygian culture format ("no" culture).
public class Client : IClient
{
public string ClientId { get; set; }
public int EngagementId { get; set; }
[MyCustomDoubleType]
public double MyValue{ get; set; } //Notice that this is my double value to be validated.
}
This is the custom validator which I have written to validate "MyValue"
public class MyCustomDoubleTypeAttribute : ValidationAttribute
{
public override bool IsValid(object value) //When I send "12,14" from client, the value gets assigned to this value is "1214". .Net thinks "," is a group separator and removes it.
{
string doubleValue = value.ToString();
try
{
Thread.CurrentThread.CurrentCulture = new CultureInfo("no");
double convertedDouble = double.Parse(doubleValue);
string convertedString = convertedDouble.ToString(Thread.CurrentThread.CurrentCulture);
if (convertedString.Equals(doubleValue))
{
return true;
}
return false;
}
catch (FormatException formatException)
{
return false;
}
}
public override string FormatErrorMessage(string name)
{
return string.Format(CultureInfo.CurrentCulture,
ErrorMessageString,
name);
}
}
So this is my problem. What I want is to get the value as I enter in the client side to the input parameter of IsValid(Object value) method.
Thanks in advance.
You might be able to use a custom model binder. I know that you can use this on a regular MVC site, so I would assume that the same or similar code could be leveraged on Web API. There is a good example of using a custom binder for parsing double values at Phil Haack's site.
The culprit is probably Json.NET that's translating 12,14 into 1214 for you. You should look into writing a custom converter that is more careful about that.
You should be able to find instructions to write your own converter on the web. Here's an example:
How to implement custom JsonConverter in JSON.NET to deserialize a List of base class objects?

Is there anyway to serilize linq object for Memcached?

I'm just start switching to memcached and currently on testing with memcached.
I'm having 2 object, I created an object and put [Serializable] on it (for instance, let call this Object1), the other object is created using Linq DBML (Object2)..
I tried to memcached List<Object1>, it work just fine, like charm, everything here is cache and loaded properly.
But then, i move on to the Linq object, now i try to add to memcached List<Object2> this does not work, it did not add to memcached at all. no key was added
I move on and change the Serialization Mode to Unidirectional, do the add again, still no hope.
Is there anyway to make this work?
Here is the simple test I just wrote, using MemcachedProvider from codeplex to demonstrate:
public ActionResult Test()
{
var returnObj = DistCache.Get<List<Post>>("testKey");
if (returnObj == null)
{
DataContext _db = new DataContext();
returnObj = _db.Posts.ToList();
DistCache.Add("testKey", returnObj, new TimeSpan(29, 0, 0, 0));
_db.Dispose();
}
return Content(returnObj.First().TITLE);
}
this is from Memcached, no STORE was called:
> NOT FOUND _x_testKey
>532 END
<528 get _x_testKey
> NOT FOUND _x_testKey
>528 END
<516 get _x_testKey
> NOT FOUND _x_testKey
>516 END
And in my SQL profiler, it called 3 query for 3 test time => Proved that the object called back from Memcached is null, then it query.
It looks like the default implementation (DefaultTranscoder) is to use BinaryFormatter; the "unidirectional" stuff is an instruction to a different serializer (DataContractSerializer), and doesn't add [Serializable].
(Note: I've added a memo to myself to try to write a protobuf-net transcoder for memcached; that would be cool and would fix most of this for free)
I haven't tested, but a few options present themselves:
write a different transcoder implementation that detects [DataContract] and uses DataContractSerializer, and hook this transcoder
add [Serializable] to your types via a partial class (I'm not convinced this will work due to the LINQ field types not being serializable)
add an ISerializable implementation in a partial class that uses DataContractSerializer
like 3, but using protobuf-net, which a: works with "unidirectional", and b: is faster and smaller than DataContractSerializer
write a serializable DTO and map your types to that
The last is simple but may add more work.
I'd be tempted to to look at the 3rd option first, as the 1st involves rebuilding the provider; the 4th option would also definitely be on my list of things to test.
I struggled with 3, due to the DCS returning a different object during deserialization; I switched to protobuf-net instead, so here's a version that shows adding a partial class to your existing [DataContract] type that makes it work with BinaryFormatter. Actually, I suspect (with evidence) this will also make it much efficient (than raw [Serializable]), too:
using System;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using ProtoBuf;
/* DBML generated */
namespace My.Object.Model
{
[DataContract]
public partial class MyType
{
[DataMember(Order = 1)]
public int Id { get; set; }
[DataMember(Order = 2)]
public string Name { get; set; }
}
}
/* Your extra class file */
namespace My.Object.Model
{
// this adds **extra** code into the existing MyType
[Serializable]
public partial class MyType : ISerializable {
public MyType() {}
void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context) {
Serializer.Serialize(info, this);
}
protected MyType(SerializationInfo info, StreamingContext context) {
Serializer.Merge(info, this);
}
}
}
/* quick test via BinaryFormatter */
namespace My.App
{
using My.Object.Model;
static class Program
{
static void Main()
{
BinaryFormatter bf = new BinaryFormatter();
MyType obj = new MyType { Id = 123, Name = "abc" }, clone;
using (MemoryStream ms = new MemoryStream())
{
bf.Serialize(ms, obj);
ms.Position = 0;
clone = (MyType)bf.Deserialize(ms);
}
Console.WriteLine(clone.Id);
Console.WriteLine(clone.Name);
}
}
}