[PostgreSQL] No longer require restart after creating the database (#467

)

Npgsql, the PostgreSQL driver, caches the database's type information on the initial connection. This causes issues when BaGet creates the database as it adds the citext extension to support case insensitive columns. BaGet will now forcefully reload the database's types after migrations are run.

See: #442
See: npgsql/efcore.pg#170 (comment)

src/BaGet.Core.Server/Extensions/IHostExtensions.cs

@@ -21,10 +21,7 @@ public static async Task RunMigrationsAsync(this IHost host, CancellationToken c
                 {
                     var ctx = scope.ServiceProvider.GetRequiredService<IContext>();
 
-                    // TODO: An "InvalidOperationException" is thrown and caught due to a bug
-                    // in EF Core 3.0. This is fixed in 3.1.
-                    // See: https://github.com/dotnet/efcore/issues/18307
-                    await ctx.Database.MigrateAsync(cancellationToken);
+                    await ctx.RunMigrationsAsync(cancellationToken);
                 }
             }
         }

src/BaGet.Core/Entities/AbstractContext.cs

@@ -1,3 +1,4 @@
+using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Metadata.Builders;
@@ -31,6 +32,9 @@ public AbstractContext(DbContextOptions<TContext> options)
 
         public Task<int> SaveChangesAsync() => SaveChangesAsync(default);
 
+        public virtual async Task RunMigrationsAsync(CancellationToken cancellationToken)
+            => await Database.MigrateAsync(cancellationToken);
+
         public abstract bool IsUniqueConstraintViolationException(DbUpdateException exception);
 
         public virtual bool SupportsLimitInSubqueries => true;

src/BaGet.Core/Entities/IContext.cs

@@ -24,5 +24,13 @@ public interface IContext
         bool SupportsLimitInSubqueries { get; }
 
         Task<int> SaveChangesAsync(CancellationToken cancellationToken);
+
+        /// <summary>
+        /// Applies any pending migrations for the context to the database.
+        /// Creates the database if it does not already exist.
+        /// </summary>
+        /// <param name="cancellationToken">A token to cancel the task.</param>
+        /// <returns>A task that completes once migrations are applied.</returns>
+        Task RunMigrationsAsync(CancellationToken cancellationToken);
     }
 }

src/BaGet.Database.PostgreSql/PostgreSqlContext.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+using System.Threading.Tasks;
 using BaGet.Core;
 using Microsoft.EntityFrameworkCore;
 using Npgsql;
@@ -24,6 +26,22 @@ public override bool IsUniqueConstraintViolationException(DbUpdateException exce
                    code == UniqueConstraintViolationErrorCode;
         }
 
+        public override async Task RunMigrationsAsync(CancellationToken cancellationToken)
+        {
+            await base.RunMigrationsAsync(cancellationToken);
+
+            // Npgsql caches the database's type information on the initial connection.
+            // This causes issues when BaGet creates the database as it may add the citext
+            // extension to support case insensitive columns.
+            // See: https://github.com/loic-sharma/BaGet/issues/442
+            // See: https://github.com/npgsql/efcore.pg/issues/170#issuecomment-303417225
+            if (Database.GetDbConnection() is NpgsqlConnection connection)
+            {
+                await connection.OpenAsync(cancellationToken);
+                connection.ReloadTypes();
+            }
+        }
+
         protected override void OnModelCreating(ModelBuilder builder)
         {
             base.OnModelCreating(builder);