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Mongo .Net Driver PipelineStageDefinitionBuilder.Project automatically ignores all Id values with a facet

When using the PipelineStageDefinitionBuilder when creating projection stages for an aggregation pipeline it appears to be always ignoring any Id values in the dataset. I'm using the Mongo .Net driver 2.8 in a .Net Core app. Below are the steps for reproduction.
The same projection worked when using the IAggregateFluent syntax on Aggregate() however I needed to use the builders for a facet. When running the builder against Aggregate it also works, however within a facet it fails to bind any Id values.
Just empty classes with id for testing (Added Type to show normal mapping works):
public class DatabaseModel
{
public Guid Id { get; set; }
public string Type { get; set; }
}
public class ProjectionClass
{
public Guid Id { get; set; }
public string Type { get; set; }
}
When I create the projection with the below, it produces a query sucessfully, however within all models returned the Id value is set to null. The query seems to have a Id_ : 0 value but the same also seems to be produced in normal aggregation so I don't think this is related?
var typeFilter = Builders<DatabaseModel>.Filter.Eq(x => x.Type, "Full");
var aggregationPipeline = new EmptyPipelineDefinition<DatabaseModel>()
.AppendStage(PipelineStageDefinitionBuilder.Match(typeFilter))
.AppendStage(PipelineStageDefinitionBuilder.Project<DatabaseModel, ProjectionClass>(x => new ProjectionClass
{
Id = x.Id,
Type = x.Type,
}));
var normalAggregationResult = await db.Aggregate(aggregationPipeline).ToListAsync();//The id's appear here
var databaseModelsFacet = AggregateFacet.Create("DatabaseModels", aggregationPipeline);
var faucetResult = db.Aggregate().Facet(databaseModelsFacet).SingleOrDefault().Facets;
var projectionModels = faucetResult.
Single(x => x.Name == "DatabaseModels")
.Output<ProjectionClass>();// This results in missing Id's (Including in nested objects with anything named Id)
Resulting mongo query
{[{
"$match" : { "Type" : "Full" } },
{ "$project" : { "Id" : "$_id", "Type" : "$Type", "_id" : 0 }
}]}
Is there any way to be able to run a projection using the pipeline builders with a facet while not ignoring the Id? I have seen examples using similar queries but haven't seen this as an issue. It could be an issue with facet as it only appears to happen when using this.
Thanks!
UPDATE 6/1/2020: Updated question after finding it only seems to occur with facet

It seems to be an Driver issue, (or other issue is when the structure does not match the fields), as Id cant simply be serialized to Id , but if you choose any other value it will work for example
[BsonNoId]
public class DatabaseModel
{
[BsonRepresentation(BsonType.ObjectId)]
public string Identifier { get; set; }
public string Type { get; set; }
}

Backendless c# desktop application saving data but by empty or null values

I have a desktop app written in c# and I added app id and key id
and used this code to add data to database but the data is always empty or null.
var film = new Film();
film.setName(“soooft”);
film.setGenre(“aaa”);
film.setPlot(“fdgveqw”);
film.setUrl(“gdfwrw”);
var f = Backendless.Data.Of<Film>().Save(film);

I googled Backendless and it's a third-party solution. (See https://github.com/Backendless/.NET-SDK)
Usage gets explained at https://backendless.com/docs/dotnet/data_data_object.html
But I'm suspicious about why you use setName(), setGenre(), setPlot and setUrl in your code. Seems your Film class is missing properties. I would expect you'd be writing this instead:
var film = new Film();
film.Name = “soooft”;
film.Genre = “aaa”;
film.Plot = “fdgveqw”;
film.Url = “gdfwrw”;
But that would mean those fields are declared as public properties in your class like this:
public class Film
{
public string Name { get; set; }
public string Genre { get; set; }
public string Plot { get; set; }
public string Url { get; set; }
}
So I don't know why you have those setName and other methods. The Backendless API specifies that these fields need to be public properties so it can read them through reflection. Your code seems to suggests that they're not proper properties as indicated by their example and my code of the Film() class.

Make sure to use public get/set properties instead of private fields and the data will be saved properly.

Serializing "string list" to JSON in C#

(I'v restated my question here: Creating class instances based on dynamic item lists)
I'm currently working on a program in Visual Studio 2015 with C#.
I have 5 list strings that contain data that I wish to serialize to a json file.
public List<string> name { get; private set; }
public List<string> userImageURL { get; private set; }
public List<string> nickname { get; private set; }
public List<string> info { get; private set; }
public List<string> available { get; private set; }
An example of the desired json file format is the fallowing:
{
"users" :
[
{
"name" : "name1",
"userImageURL" : "userImageURL1",
"nickname" : "nickname1",
"info" : "info1",
"available" : false,
},
{
"name" : "name2",
"userImageURL" : "userImageURL2",
"nickname" : "nickname2",
"info" : "info2",
"available" : false,
},
{
"name" : "name3",
"userImageURL" : "userImageURL3",
"nickname" : "nickname3",
"info" : "info3",
"available" : false,
},
{
"name" : "name4",
"userImageURL" : "userImageURL4",
"nickname" : "nickname4",
"info" : "info4",
"available" : false,
}
]
}
Note that there might be errors in the json example above.
I've tried combining the 5 lists to create 1 list to serialize it using the following code:
users = new List<string>(name.Count + userImageURL.Count + nickname.Count + info.Count + available.Count);
allPlayers.AddRange(name);
allPlayers.AddRange(userImageURL);
allPlayers.AddRange(nickname);
allPlayers.AddRange(info);
allPlayers.AddRange(available);
Then I serialize the list with the fallowing code:
string data = JsonConvert.SerializeObject(users);
File.WriteAllText("data.json", data);
This just creates an array of unorganized objects. I wish to know how can I organize them as expressed in the format above.
PS: I'm pretty new to coding as you can tell. Sorry if I'm not expressing the question correctly or using the right terminology. Also, this is not the original code. The code creates this lists which I wish to serialize into a json file.
PSS: This data is collected using HtmlAgilityPack. I asked a question yesterday asking how could I parse an html file and serialize it's data to a json file. Using HtmlAgilityPack to get specific data in C# and serialize it to json . As nobody answered, I decided to try and do it myself. The method that I used may not be the best, but it is what I could do with the knowledge that I have.

I would suggest refactoring your code to start with - instead of having 5 "parallel collections", have a single collection of a new type, User:
public class User
{
public string Name { get; set; }
public string ImageUrl { get; set; }
public string NickName { get; set; }
public string Info { get; set; }
public bool Available { get; set; }
}
...
// In your containing type
public List<User> Users { get; set; }
This is likely to make life simpler not just for your JSON, but for the rest of the code too - because you no longer have the possibility of having more nicknames than image URLs, etc. In general, having multiple collections that must be kept in sync with each other is an antipattern. There are times where it's appropriate - typically providing different efficient ways of retrieving the same data - but for something like this it's best avoided.

It is actually what Jon says, but to move from your parallel lists to Jon's single list you need something like (assuming all lists have the same number of elements in the same order):
Users = new List<User>();
for (var i = 0; i < name.Count; i++)
{
Users.Add(new User
{
Available = available[i],
ImageUrl = userImageURL[i],
Info = info[i],
Name = name[i],
NickName = nickname[i]
});
}
And then serialise the Users list.

How do you get the Id field for a newly inserted item using the .NET client for Azure Mobile

I'm trying to use Azure Mobile Services to create a backend for an asynchronous multiplayer game. I'm using a sql database and a .NET backend on WAMS, calling the service from the .NET client (Xamarin.iOS specifically atm).
The class for the item being into the db:
public class Match {
public string Id { get; set; }
public int Challengers { get; set; }
string GameData { get; set; }
public List<string> Players { get; set; }
public string LastPlayer { get; set; }
public string Message { get; set; }
public string NextPlayer { get; set; }
public int PlayerGroup { get; set; }
}
I'm inserting it into the database using:
var matchtable = MobileService.GetTable <Match> ();
CurrentMatch = new Match {
Message = variant.ToString () + ", " + CurrentUser + " vs ??",
NextPlayer = CurrentUser,
Players = players,
PlayerGroup = playerGroup,
Challengers = 0,
Game = null,
LastPlayer = null
};
await matchtable.InsertAsync (CurrentMatch);
I'm then doing other things that will affect the match and need to update it again later, but I don't have an Id field for the CurrentMatch to be able to do the update. Everything I can find tells me that I should get the Id field back after the insert (either the method returning something or updating CurrentMatch itself with it), but it must all be talking about a javascript backend or different client or something. The InsertAsync method in the .NET client has no return value (well, technically returns Task) and the CurrentMatch doesn't get updated with the Id field from the call (also makes sense since it's not a ref or out parameter).
How on earth am I supposed to get the Id field for an object I just inserted into the database?

I'm assuming you are using the latest version of the Mobile Services client SDK, in which case you are calling this InsertAsync method here.
You're right that the parameter is not a ref or out parameter, but it can modify the fields of the object you passed in. In this case, it will modify the contents of the Match object.
My guess is that there is another code issue that's interfering. Or, if that code snippet is in a method, make sure it returns a Task and you await it before you check the contents of Id. A simple console log should help here.
If this doesn't solve the problem, then please include more context, otherwise the code you've written should behave as I've said.

MVC 4.0 Controller cannot find seeded data

I am attempting to seed data for an MVC 4 project using SQL server 4.0 as the database engine, using the Microsoft MVC music store tutorial as an example. I have set up a seed and DB context models, but the controller is not able to find the data. I have verified that the the database file is created in App_Data and verified that SetIntitializer is correctly set up in Application_Start. Here is what I have for code:
Seed data:
namespace RationalMethodApp.Models
{
public class StartData : CreateDatabaseIfNotExists<RationalMethodEntities>
{
protected override void Seed(RationalMethodEntities context)
{
new List<Basin>
{
new Basin {
basinId = 1, // attempting to force a key value, will remove
Name = "Replace me with a real basin",
Location = "In a real location",
drainageArea = 0.0M
}
}.ForEach(b => context.Basins.Add(b));
Controller:
public ActionResult Index(int? bsnId)
{
if (bsnId == null) // here to force a key value, will change
bsnId = 1;
var basin = rmDb.Basins.Find(bsnId);
return View(basin);
}
The context class is:
namespace RationalMethodApp.Models
{
public class RationalMethodEntities : DbContext
{
public DbSet<Basin> Basins { get; set; }
public DbSet<SubArea> SubAreas { get; set; }
public DbSet<IdfCurve> IdfCurves { get; set; }
public DbSet<Analysis> Analyses { get; set; }
public DbSet<FlowSegment> FlowSegments { get; set; }
public DbSet<SheetFlowN> SheetFlowNs { get; set; }
public DbSet<RunoffCoefficient> RunoffCoefficients { get; set; }
public DbSet<StormFrequency> stormFrequencies { get; set; }
}
}
The debugger tells me that the "basin" object is still null in the controller after the .Find. This must be a simple, basic thing that I have overlooked, but all of the help I can find on-line assumes that the askers know what they are doing - not true in my case! I have also checked the discussion at Entity Framework database seed doesn't seed
but this does not seem to be the answer. Please bear with a total noob question.

You don't show the full code of you seed, so i can't really be sure, but you might be missing the Context.Changes().
As well you wrote
public class StartData : CreateDatabaseIfNotExists<RationalMethodEntities>
If you don't delete your database before the application start, it won't do anything as the db already exists.
You could use :
public class StartData : DropCreateDatabaseAlways <RationalMethodEntities>
to drop it every time you start or
public class StartData : DropCreateDatabaseAlways <DropCreateDatabaseIfModelChanges >
to drop db when Model changes (which is great for start of dev)
To debug: Drop your database, kill your application server (so it goes back to application start), breakpoint in your seed. Start Debug, if it goes in seed, check that data is in it after SaveChange().