Initial curated itworx-knowledge-hub source from 3b1751d0d9dee551aa6994eee0093704dc334817

tests/backend/ItWorx.KnowledgeHub.IntegrationTests/Operations/SchemaGuardTests.cs

@@ -0,0 +1,89 @@
+using ItWorx.KnowledgeHub.Infrastructure.Persistence;
+using ItWorx.KnowledgeHub.IntegrationTests.Infrastructure;
+using Microsoft.EntityFrameworkCore;
+using Npgsql;
+
+namespace ItWorx.KnowledgeHub.IntegrationTests.Operations;
+
+/// <summary>Proves M7-A02 ("Startup refuses unsafe schema drift") against a real,
+/// freshly migrated PostgreSQL database — forward migration (the normal path) must
+/// stay silent, and a database with an applied migration this build's assembly does
+/// not know about must be refused before any data-mutating call.</summary>
+[Collection(PostgresTestGroup.Name)]
+public sealed class SchemaGuardTests(PostgresContainerFixture postgres)
+{
+    [Fact]
+    public async Task A_freshly_migrated_database_with_only_known_migrations_is_accepted()
+    {
+        await using var target = await RestoreTargetDatabase.CreateAsync(postgres);
+        var options = new DbContextOptionsBuilder<KnowledgeHubDbContext>()
+            .UseNpgsql(target.ConnectionString, npgsql => npgsql.MigrationsAssembly(typeof(KnowledgeHubDbContext).Assembly.GetName().Name))
+            .UseSnakeCaseNamingConvention()
+            .Options;
+        await using var db = new KnowledgeHubDbContext(options);
+
+        await SchemaGuard.EnsureCompatibleAsync(db.Database, CancellationToken.None);
+    }
+
+    [Fact]
+    public async Task An_unmigrated_brand_new_database_is_accepted_nothing_can_be_ahead_of_an_empty_history()
+    {
+        var databaseName = $"schema_guard_fresh_{Guid.NewGuid():N}";
+        await using (var admin = new NpgsqlConnection(postgres.AdminConnectionString))
+        {
+            await admin.OpenAsync();
+            await using var create = new NpgsqlCommand($"CREATE DATABASE \"{databaseName}\"", admin);
+            await create.ExecuteNonQueryAsync();
+        }
+
+        try
+        {
+            var connectionString = new NpgsqlConnectionStringBuilder(postgres.AdminConnectionString) { Database = databaseName }.ConnectionString;
+            var options = new DbContextOptionsBuilder<KnowledgeHubDbContext>()
+                .UseNpgsql(connectionString, npgsql => npgsql.MigrationsAssembly(typeof(KnowledgeHubDbContext).Assembly.GetName().Name))
+                .UseSnakeCaseNamingConvention()
+                .Options;
+            await using var db = new KnowledgeHubDbContext(options);
+
+            // No exception, even though the migrations-history table does not exist yet.
+            await SchemaGuard.EnsureCompatibleAsync(db.Database, CancellationToken.None);
+        }
+        finally
+        {
+            await using var admin = new NpgsqlConnection(postgres.AdminConnectionString);
+            await admin.OpenAsync();
+            await using var drop = new NpgsqlCommand($"DROP DATABASE IF EXISTS \"{databaseName}\" WITH (FORCE)", admin);
+            await drop.ExecuteNonQueryAsync();
+        }
+    }
+
+    [Fact]
+    public async Task A_database_with_an_applied_migration_unknown_to_this_build_is_refused()
+    {
+        await using var target = await RestoreTargetDatabase.CreateAsync(postgres);
+
+        // Simulate a database that is ahead of this build (e.g. rolled back to an
+        // older image against a newer database) by recording a migration this
+        // assembly has never heard of.
+        await using (var connection = new NpgsqlConnection(target.ConnectionString))
+        {
+            await connection.OpenAsync();
+            await using var insert = new NpgsqlCommand(
+                "INSERT INTO \"public\".\"__EFMigrationsHistory\" (migration_id, product_version) VALUES (@id, @version)",
+                connection);
+            insert.Parameters.AddWithValue("id", "99999999999999_FutureMigrationFromAnUnreleasedBuild");
+            insert.Parameters.AddWithValue("version", "99.0.0");
+            await insert.ExecuteNonQueryAsync();
+        }
+
+        var options = new DbContextOptionsBuilder<KnowledgeHubDbContext>()
+            .UseNpgsql(target.ConnectionString, npgsql => npgsql.MigrationsAssembly(typeof(KnowledgeHubDbContext).Assembly.GetName().Name))
+            .UseSnakeCaseNamingConvention()
+            .Options;
+        await using var db = new KnowledgeHubDbContext(options);
+
+        var exception = await Assert.ThrowsAsync<SchemaDriftException>(
+            () => SchemaGuard.EnsureCompatibleAsync(db.Database, CancellationToken.None));
+        Assert.Contains("FutureMigrationFromAnUnreleasedBuild", exception.Message, StringComparison.Ordinal);
+    }
+}