telegram-bot/modules/RichSiteSummary/Data/RichSiteSummaryContext.cs

using Kruzya.TelegramBot.Core.EF;
using Microsoft.EntityFrameworkCore;

namespace Kruzya.TelegramBot.RichSiteSummary.Data;

public class RichSiteSummaryContext : AutoSaveDbContext
{
    /// <summary>
    /// Repository with all feeds in database.
    /// </summary>
    public DbSet<Feed> Feeds { get; set; }
        
    /// <summary>
    /// Repository with all posts in database.
    /// </summary>
    public DbSet<Post> Posts { get; set; }
        
    /// <summary>
    /// Repository with all subscriptions in database.
    /// </summary>
    public DbSet<Subscriber> Subscriptions { get; set; }

    /// <summary>
    /// Ensures the database is created and calls parent constructor.
    /// </summary>
    /// <param name="options"></param>
    public RichSiteSummaryContext(DbContextOptions<RichSiteSummaryContext> options) : base(options)
    {
        Database.EnsureCreated();
    }

    /// <summary>
    /// Setup the additional unique keys.
    /// </summary>
    /// <param name="modelBuilder"></param>
    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        // Setup unique keys for Feed entity.
        modelBuilder.Entity<Feed>().HasIndex(feed => feed.Url).IsUnique();
        modelBuilder.Entity<Feed>().HasIndex(feed => feed.HomePage).IsUnique();
            
        // Setup unique keys for Post entity.
        modelBuilder.Entity<Post>()
            .HasOne(p => p.Feed)
            .WithMany(f => f.Posts)
            .HasForeignKey(p => p.FeedId);

        modelBuilder.Entity<Post>().HasIndex(post => 
            new {post.FeedId, post.Url}).IsUnique();

        // Setup foreign keys for Subscriber entity.
        modelBuilder.Entity<Subscriber>()
            .HasOne(s => s.Feed)
            .WithMany(f => f.Subscribers)
            .HasForeignKey(s => s.FeedId);
    }
}