Query Your Data With ASP.NET Core, OData, and the MongoDB Entity Framework Core Provider

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dotnet add package MongoDB.EntityFrameworkCore

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// requires using MongoDB.Bson;
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public class Movie
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{
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    public string Id { get; set; } = ObjectId.GenerateNewId().ToString();
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    public string Title { get; set; } = string.Empty;
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    public string? Plot { get; set; }
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    public IEnumerable<string>? Genres { get; set; }
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    public IEnumerable<string>? Cast { get; set; }
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    // additional properties as required
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}

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// requires using Microsoft.EntityFrameworkCore;
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// requires using MongoDB.Bson;
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// requires using MongoDB.EntityFrameworkCore.Extensions;
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public class MflixDbContext : DbContext
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{
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    public MflixDbContext(DbContextOptions options)
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        : base(options)
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    {
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    }
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    public DbSet<Movie> Movies { get; init; }
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    protected override void OnModelCreating(ModelBuilder modelBuilder)
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    {
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        base.OnModelCreating(modelBuilder);
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        var movieEntity = modelBuilder.Entity<Movie>();
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        movieEntity.ToCollection("movies");
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        movieEntity.Property(x => x.Id)
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            .HasElementName("_id")
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            .HasConversion<ObjectId>();
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        movieEntity.Property(x => x.Title).HasElementName("title");
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        movieEntity.Property(x => x.Plot).HasElementName("plot");
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        movieEntity.Property(x => x.Genres).HasElementName("genres");
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        movieEntity.Property(x => x.Cast).HasElementName("cast");
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    }
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}

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// requires using Microsoft.EntityFrameworkCore;
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// requires using MongoDB.Driver;
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// requires using MongoDBEFODataVerify;
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builder.Services.AddSingleton<IMongoClient>(prov =>
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{
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    // Retrieve connection string from configuration
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    return new MongoClient("<your MongoDB connection string>");
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});
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builder.Services.AddSingleton(prov =>
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{
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    var client = prov.GetRequiredService<IMongoClient>();
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    // Retrieve database name from configuration
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    return client.GetDatabase("sample_mflix");
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});
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builder.Services.AddDbContext<MflixDbContext>((prov, options) =>
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{
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    var database = prov.GetRequiredService<IMongoDatabase>();
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    options.UseMongoDB(
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        database.Client, 
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        database.DatabaseNamespace.DatabaseName);
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});

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dotnet add package Microsoft.AspNetCore.OData

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// requires using Microsoft.OData.Edm;
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// requires using Microsoft.OData.ModelBuilder;
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IEdmModel GetEdmModel()
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{
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    var model = new ODataConventionModelBuilder();
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    model.EnableLowerCamelCase();
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    model.EntitySet<Movie>("Movies");
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    return model.GetEdmModel();
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}

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// requires using Microsoft.OData;
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// This should be already in the code
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builder.Services
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    .AddControllers()
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// This is new
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    .AddOData(options => options
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        .Select()
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        .Filter()
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        .OrderBy()
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        .Count()
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        .SetMaxTop(100)
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        .AddRouteComponents("odata", GetEdmModel()));

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// requires using Microsoft.AspNetCore.OData.Query;
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// requires using Microsoft.AspNetCore.OData.Routing.Controllers;
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public class MoviesController : ODataController
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{
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    private readonly MflixDbContext _dbContext;
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    public MoviesController(MflixDbContext dbContext)
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    {
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        _dbContext = dbContext;
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    }
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    [EnableQuery(
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        PageSize = 1000, 
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        AllowedOrderByProperties = "title, plot")]  
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    public IQueryable<Movie> Get()
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    {
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        return _dbContext.Movies;
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    }
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}

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{
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    "@odata.context": "https://localhost:7104/odata/$metadata#Movies",
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    "value": [
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        {
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            "id": "573a1390f29313caabcd4135",
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            "title": "Blacksmith Scene",
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            "plot": "Three men hammer on an anvil...",
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            "genres": [
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                "Short"
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            ],
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            "cast": [
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                "Charles Kayser",
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                "John Ott"
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            ]
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        },
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        // 999 more results
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    ],
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    "@odata.nextLink": "https://localhost:7104/odata/Movies?$skip=10"
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}

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// requires using Microsoft.AspNetCore.OData.Query;
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// requires using Microsoft.AspNetCore.OData.Routing.Controllers;
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// requires using MongoDB.Driver;
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public class MoviesController : ODataController
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{
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    private readonly IMongoCollection<Movie> _collMovies;
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    public MoviesController(IMongoDatabase db)
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    {
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        _collMovies = db.GetCollection<Movie>("movies");
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    }
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    [EnableQuery(
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        PageSize = 1000, 
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        AllowedOrderByProperties = "title, plot")]
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    public IQueryable<Movie> Get()
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    {
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        return _collMovies.AsQueryable();
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    }
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}

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// requires using Microsoft.AspNetCore.OData.Routing.Controllers;
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// requires using MongoDB.AspNetCore.OData.Query;
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// requires using MongoDB.Driver;
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public class MoviesController : ODataController
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{
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    private readonly IMongoCollection<Movie> _collMovies;
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    public MoviesController(IMongoDatabase db)
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    {
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        _collMovies = db.GetCollection<Movie>("movies");
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    }
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    // Change this from EnableQuery to MongoEnableQuery
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    [MongoEnableQuery(
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        PageSize = 1000, 
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        AllowedOrderByProperties = "title, plot")]
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    public IQueryable<Movie> Get()
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    {
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        return _collMovies.AsQueryable();
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    }
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}