System.Text.Json serializer issues

.NET SDK
1

The system.text.json works fine when writing the document, i see all fields in the parent classes, but when loading from the database, only properties in the top most class get serialized.

Example:

Profile is base, EditableProfile is child.
I write EditableProfile to couchbase, all properties are there. When reading, i only see properties in EditableProfile get populated, nothing in Profile.

Am i missing something?

2

I don’t see System.text.json being used for the serializer in any of the examples. I believe the default serializer is JSON.NET

There’s a thread here Use System.Text.Json as DefaultSerializer?

Usually what helps for debugging is the code and the documents. And the EditableProfile and Profile classes.

3

It sounds like you may be using polymorphism in your document types. If so, you’ll need to use the JsonPolymorphic attribute or some other method of adding discriminators for deserialization.

https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/polymorphism

4

i already have

[JsonPolymorphic]
[JsonDerivedType(typeof(EditableProfile))]

5

Can you provide a full example of the types and calls?

6 
[JsonPolymorphic(
    UnknownDerivedTypeHandling = JsonUnknownDerivedTypeHandling.FallBackToNearestAncestor)]
[JsonDerivedType(typeof(EditableProfile))]
public class Profile
{

    [JsonPropertyName("profileGuid")]
    public string ProfileGuid;

    [JsonPropertyName("updatedAt")]
    public DateTime? UpdatedAt { get; set; }

    [JsonPropertyName("createdAt")]
    public DateTime? CreatedAt { get; set; }

    [JsonPropertyName("rvn")]
    public int Rvn { get; set; } = 0;
    
    [JsonPropertyName("accountId")]
    public string AccountId { get; set; } = "";

the document is:

{
  "accountIds": "Bhdsfdsfds",
  "updatedAt": "2024-04-16T23:41:24.0967139Z",
  "createdAt": "2024-04-16T23:41:24.0967682Z",
  "rvn": 0,
  "accountId": "sssssss",
  "type": "profile_main"
}

Editable profile has this prop:

public class EditableProfile : Profile
{
    [JsonPropertyName("accountIds")]
    public string AccountIds { get; set; } = "Bhdsfdsfds";

Only property to get serialized is accountIds.

    public async Task<EditableProfile> FindByKey(string accountId, string profileType, bool b)
    {
        var queryParameters = new Couchbase.Query.QueryOptions();
        queryParameters.Parameter("accountId", accountId);
        queryParameters.Parameter("profileType", profileType);
        string query;
        query = $@"SELECT * from profile WHERE accountId = $accountId AND type = $profileType LIMIT 1";
        var results = await _scopeService.QueryAsync<EditableProfile>(query, queryParameters);
        var Profile = await results.Rows.FirstOrDefaultAsync();
        return Profile;
    }
7 
builder.Services.AddCouchbase(options =>
{
    builder.Configuration.GetSection("Couchbase").Bind(options);

    var jsonOptions = new JsonSerializerOptions
    {
        PropertyNameCaseInsensitive = true,
        IncludeFields = true,
        WriteIndented = true
    };
    
    options.WithSerializer(SystemTextJsonSerializer.Create(jsonOptions));

});

this is how i set the serializer

8

Try changing the projection in the query to profile.* instead of just *. I think you just have an issue with the query result rows being nested.

9

Sorry not sure i understand, new to couchbase

10

query = $@“SELECT profile.* from profile WHERE accountId = $accountId AND type = $profileType LIMIT 1”; like this?

11

Now its working, i am not sure why. Why does profile.* matter than just *?

12

Yes. Sorry, I’m responding from my phone so it’s hard to type everything out, especially code.

13

It has to do with the nature of SQL++ and structured data as compared to traditional SQL and flat data.

When you’re joining multiple extents such as this:

SELECT * FROM profile INNER JOIN user ON user.id = profile.userId

Then each extent is returned in the query rows array nested based on its name:

[
  {
    "profile": { "userId": 1, email: "user@gmail.com" },
    "user": { "id": 1, name: "User" }
  },
  {
    "profile": { "userId": 2, email: "user2@gmail.com" },
    "user": { "id": 2, name: "User2" }
  }
]

For consistency, this same rule applies to queries that only have a single extent, such as yours. So your original query output would be something like this:

[
  {
    "profile": {
      "accountIds": "Bhdsfdsfds",
      "updatedAt": "2024-04-16T23:41:24.0967139Z",
      "createdAt": "2024-04-16T23:41:24.0967682Z",
      "rvn": 0,
      "accountId": "sssssss",
      "type": "profile_main"
    }
  }
]

By using profile.* in the projection instead of * you’re requesting the attributes from the specific profile extent of the query, rather than requesting all extents, so it will return unnested:

[
  {
    "accountIds": "Bhdsfdsfds",
    "updatedAt": "2024-04-16T23:41:24.0967139Z",
    "createdAt": "2024-04-16T23:41:24.0967682Z",
    "rvn": 0,
    "accountId": "sssssss",
    "type": "profile_main"
  }
]
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14

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