ASP.NET MongoDb unstructured data exception - c#

I struggle with C# ASP.NET sending (partially) unstructured data to MongoDb.
How is it possible to add a field with unstructured data (unstructuredInfo) to a otherwise mapped class?
If not - how is BsonDocument or any other clever solution, anyway? I always get JsonExceptions with BsonDocuments.
Get Method works fine. I can't get it working for a Post Method. I get JsonExceptions.
... System.Text.Json.JsonException: The JSON value could not be converted to MongoDB.Bson.BsonDocument. ...
I setup a quick Github Repo with the test project.
https://github.com/Maxoper/MongoDbProblem
public class Movie
{
[BsonId]
[BsonRepresentation(BsonType.ObjectId)]
public string Id { get; set; }
public string Title { get; set; }
public int Year { get; set; }
public string Summary { get; set; } = null;
public List<string> Actors { get; set; }
[BsonExtraElements]
public BsonDocument UnstructuredInfo { get; set; }
}
public class MoviesService
{
private readonly IMongoCollection<Movie> _movies;
public MoviesService(IOptions<MoviesDatabaseSettings> options)
{
var mongoClient = new MongoClient(options.Value.ConnectionString);
_movies = mongoClient.GetDatabase(options.Value.DatabaseName)
.GetCollection<Movie>(options.Value.MoviesCollectionName);
}
public async Task Create(Movie newMovie) =>
await _movies.InsertOneAsync(newMovie);
app.MapPost("/api/movies", async (MoviesService moviesService, Movie movie) =>
{
await moviesService.Create(movie);
return Results.Ok();
});

The problem is that the JSON cannot be converted to BsonDocument out of the box. Either you create a custom converter or you change the type of the property to IDictionary<string, object>:
[BsonExtraElements]
public IDictionary<string, object> UnstructuredInfo { get; set; }
This way, the JSON serializer does not have to deal with MongoDB specific classes like BsonDocument and you have better chances that everything can be serialized.

Related

Json with data inconsistency

I got this strange API response from one external service:
{emplooye: "Michael",age:"25",attachments:[{idAttachment: "23",attachmentPath:"C://Users/1"},{idAttachment: "24",attachmentPath:"C://Users/2"}]},{emplooye: "John",age:"30",attachments:{idAttachment: "25",attachmentPath:"C://Users/3"}}
Has anyone ever faced a situation where sometimes the "Attachment" property can be an array, sometimes it can be an object? I created a class to manipulate the data, but when I find an object, the code breaks.
I'm doing this in C#.
Class Used
public class Attachments
{
public string idAttachment{ get; set; }
public string attachmentPath{ get; set; }
}
public class Root
{
public string emplooye {get; set;}
public string age {get;set}
public List<Attachments> attachments { get; set; } = new List<Attachments>();
}
your json is not even close to json, should be something like this
var json = "[{\"emplooye\":\"Michael\",\"age\":\"25\",\"attachments\":[{\"idAttachment\":\"23\",\"attachmentPath\":\"C://Users/1\"},{\"idAttachment\":\"24\",\"attachmentPath\":\"C://Users/2\"}]},{\"emplooye\":\"John\",\"age\":\"30\",\"attachments\":{\"idAttachment\":\"25\",\"attachmentPath\":\"C://Users/3\"}}]";
Using Newtonsoft.Json you can create a JsonConstructor
using Newtonsoft.Json;
List<Data> data= JsonConvert.DeserializeObject<List<Data>>(json);
public class Data
{
public string emplooye { get; set; }
public string age { get; set; }
public List<Attachments> attachments { get; set; }
[JsonConstructor]
public Data(JToken attachments)
{
if (attachments.Type.ToString() == "Array")
this.attachments = attachments.ToObject<List<Attachments>>();
else
this.attachments = new List<Attachments> { attachments.ToObject<Attachments>() };
}
public Data() {}
}
public class Attachments
{
public string idAttachment { get; set; }
public string attachmentPath { get; set; }
}
You can use Newtonsoft to parse to a JToken which will handle the typing for you, but with the downside of not having a stable and predictable class to deserialize to automatically
Then, you would want to check its type, which returns a JTokenType enum
Once you know what the underlying types are, marshal the data into your DTO classes
JToken responseJT = JToken.Parse(json); //json string
if (responseJT.Type == JTokenType.Array)
//its an array, handle as needed ...
else if (responseJT.Type == JTokenType.Object)
//its an object, handle as needed ...
Personally, I would keep the attachments property as a List<Attachments> and if the JToken has a JSON object I would just set it as the [0] index of that property. This way things stay consistent and you can use LINQ on that property with ease

.NET Core API REST C# List into List is null

I'm developing an api in net core.
I've done a post function in which I send an object containing multiple parameters and a list within another list.
When I'm debugging the code the function is called correctly but I find that the second list always arrives null.
The rest of the data arrives at you correctly. I have done different tests with other objects and everything works correctly.
It is this case in which the list within another the second one arrives null.
My code:
example request input
{
"Name": "TestName",
"Related1":
[{
"id1": "TestNameRelated1",
"Related2":
[{
"id2": "TestNameRelated2"
}]
}]
}
[HttpPost]
public resultExample Test([FromBody]TestClass test)
{
//do something
}
[DataContract]
public class TestClass
{
[DataMember]
public string Name { get; set; }
[DataMember]
public List<TestClassArray> Related1 { get; set; }
}
[DataContract]
public class TestClassArray
{
[DataMember]
public string id1 { get; set; }
[DataMember]
public List<TestClassArray2> Related2 { get; set; }
}
[DataContract]
public class TestClassArray2
{
[DataMember]
public string id2 { get; set; }
}
This api was previously made in .NET framework 4.8 and this case worked correctly.
Now I'm passing the api to .Net5.
Could it be that in .Net5 it is not allowed to pass lists within other lists?
Do you have to enable some kind of configuration to be able to do this now?
You need use class/DTO with constructor like shown below and you should be good to go. I have uploaded this sample API app's code working with .net5.0 on my GitHub here.
public class TestClass
{
public TestClass()
{
Related1 = new List<TestClassArray>();
}
public string Name { get; set; }
public List<TestClassArray> Related1 { get; set; }
}
public class TestClassArray
{
public TestClassArray()
{
Related2 = new List<TestClassArray2>();
}
public string id1 { get; set; }
public List<TestClassArray2> Related2 { get; set; }
}
public class TestClassArray2
{
public string id2 { get; set; }
}
public class ResultExample
{
public string StatusCode { get; set; }
public string Message { get; set; }
}
Controller Post Method
[HttpPost]
[ProducesResponseType(typeof(ResultExample), 200)]
public ResultExample Post([FromBody] TestClass test)
{
ResultExample testResult = new ResultExample();
TestClass test2 = new TestClass();
TestClassArray testClassArray = new TestClassArray();
TestClassArray2 testClassArray2 = new TestClassArray2();
test2.Name = test.Name;
foreach (var item in test.Related1)
{
foreach (var item2 in item.Related2)
{
testClassArray2.id2 = item2.id2;
}
testClassArray.Related2.Add(testClassArray2);
}
test2.Related1.Add(testClassArray);
Console.WriteLine(test2);
testResult.Message = "New Result added successfullly....";
testResult.StatusCode = "201";
return testResult;
}
Swagger Input Sample Payload
Post Controller Result
Response of Sample input payload,(You can change it to default 201 response code as well)
I had a similar issue.
API method shows List was null
In my case a date field was not well formatted
So I use SimpleDateFormat on Android Studio with a correct datetime format
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss",Locale.US);
item.setDate(dateFormat.format(calendar.getTime()));
and works fine

How can I deserialize JSON to a custom type which has a property of type IEnumerable<dynamic>?

I'm writing a console app to retrieve JSON data from a 3rd party API. I have no control over the API data structures or functionality.
Several of the calls I make will return multiple 'pages' of data. The data is a collection of objects of a certain type e.g. User.
I have created classes in my app to match the various data types from the API.
public class User
{
[JsonProperty("id")]
public int ID { get; set; }
[JsonProperty("first_name")]
public string FirstName { get; set; }
[JsonProperty("last_name")]
public string LastName { get; set; }
}
public class FooBar
{
[JsonProperty("foo")]
public string Foo { get; set; }
[JsonProperty("bar")]
public string Bar { get; set; }
}
The API response is always in the same format for these calls. While the actual object types in the "data" array will differ depending on what call has been made.
{
"paging":{"page":1},
"data":[{<object>}, {<object>}, {<object>},...]
}
I have created a class to try to deserialize these. The dynamic[] type for the Data property is for illustrative purposes and I am happy to change it if there is a better approach.
public class ApiResponseObject
{
[JsonProperty("paging")]
public Paging PagingInfo { get; set; }
[JsonProperty("data")]
public dynamic[] Data { get; set; }
}
And I would like to have the Data collection resolve to the appropriate type for the objects it contains. e.g.
string userJson = "{\"paging\":{\"page\":1},\"data\":[{\"id\":1,\"first_name\":\"Joe\",\"last_name\":\"Bloggs\"},{\"id\":2,\"first_name\":\"Jane\",\"last_name\":\"Doe\"}]}"; // json string would come from API
string foobarJson = "{\"paging\":{\"page\":1},\"data\":[{\"foo\":\"Lorem\",\"bar\":\"Ipsum\"},{\"foo\":\"Dolor\",\"bar\":\"Amet\"}]}";
var userResponse = JsonConvert.DeserializeObject<ApiResponseObject>(userJson);
var foobarResponse = JsonConvert.DeserializeObject<ApiResponseObject>(foobarJson);
The deserialization succeeds but the Data collection is of type JObject and cannot be cast into the correct type (User, FooBar).
I am trying to avoid having to write specific response object classes for each request if possible.
I will know what type of object I am expecting in the collection when I am requesting it so I could pass that type to the deserializer but I'm not clear on how to achieve that in this particular scenario.
Something like the below psuedo code would be ideal.
var userResponse = JsonConvert.DeserializeObject<ApiResponseObject<User>>(userJson);
Thanks for your help!
You can use the generic type T, like this :
public class ApiResponseObject<T>
{
[JsonProperty("paging")]
public Paging PagingInfo { get; set; }
[JsonProperty("data")]
public T[] Data { get; set; }
}

How Can I Deserialize JSON Data Using C#?

I have seen some other questions like this, but those are quite complex JSON data's that have objects within objects. Although the JSON I'm working with is never static, I doubt it's as complex as those. Also, it's my first time using JSON with C# so I'm a little clueless.
What I'm trying to achieve is to separate the data that is received from an API that I prompt using WebRequest in C#.
{
"johhny.debt": {
"id":35187540,
"name":"johnny.debt",
"profileIconId":786,
"Level":30,
"revisionDate":1428019045000
}
}
The returned JSON data is in a fashion like thereof.
I want to be able to access all of the properties of the above string in the following manner:
ID :
Name:
~~
~~
~~
... and so forth.
I'm assuming some type of class has to be made for this?
All help is appreciated, thank you all in advance.
Install Json.Net from Nuget
Install-Package Newtonsoft.Json
https://www.nuget.org/packages/Newtonsoft.Json/
Declare class for inner object ({"id":..., "name": ... }):
public class InnerObject
{
[JsonProperty("id")]
public int Id { get; set; }
[JsonProperty("name")]
public string Username { get; set; }
[JsonProperty("profileIconId")]
public int ProfileIconId { get; set; }
[JsonProperty("level")]
public int Level { get; set; }
[JsonProperty("revisionDate")]
public string RevisionDate { get; set; }
}
As you can see you can specify rename mapping from json fields to .Net object properties using JsonPropertyAttribute.
Read your json to Dictionary<string,InnerObject> and get value of "johhny.debt" key:
var dict = JsonConvert.DeserializeObject<Dictionary<string, InnerObject>>(jsonText);
var johhny = dict["johhny.debt"];
Or if your need always to parse exact json property 'johhny.debt', you could create root object class:
public class RootObject
{
[JsonProperty("johhny.debt")]
public InnerObject JohhnyDept { get; set; }
}
And deserialize it:
var root = JsonConvert.DeserializeObject<RootObject>(jsonText);
var johhny = root.JohhnyDebt;
Just Create a class like this
public class RootObject
{
public int Id { get; set; }
public string name { get; set; }
public int profileIconId { get; set; }
public int Level { get; set; }
public string revisionDate { get; set; }
}
then install json.Net and this code to your main method
var jsonObject=JsonConvert.DeserializeObject<RootObject>(jsonText);
That's all
Update
var obj = JObject.Parse(json);
var RootObject = new RootObject()
{
Id = (int)obj["johhny.debt"]["id"],
Level = (int)obj["johhny.debt"]["Level"],
name = (string)obj["johhny.debt"]["name"],
profileIconId = (int)obj["johhny.debt"]["profileIconId"],
revisionDate = (string)obj["johhny.debt"]["revisionDate"]
};

Filling list with Json data and getting the objects from it

I have a php webservice which gets the data from database and returns it as json data.
Json data
{"faqs":
[
{"faq":{"id":"123"}},
{"faq":{"id":"124"}}
]
}
Object classes
public class FaqList
{
public List<Faq> faqs { get; set; }
}
public class Faq
{
public string id { get; set; }
}
Test class
var client = new HttpClient();
HttpResponseMessage response = await client.GetAsync(new Uri("http://www.mydomain.com/webservice/7/server.php"));
var jsonString = await response.Content.ReadAsStringAsync();
FaqList list = JsonConvert.DeserializeObject<FaqList>(jsonString);
list.faqs.Count() => 2
list.faqs[0].id => NULL !!
I fill all the objects to the 'list'. With count test I see that it's filled. But if I try to get an objects from it, I get null error.
So, how can I correctly fill my list so that I can get the objects from it?
http://json2csharp.com/ suggests these definitions. (One more class Faq2)
public class Faq2
{
public string id { get; set; }
}
public class Faq
{
public Faq2 faq { get; set; }
}
public class RootObject
{
public List<Faq> faqs { get; set; }
}

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