Parameter validation and other DB manager improvements (#1459)

### Parameter validation

In `statement()` calls of `TenantDatabaseManager`s, use parameter
binding when possible. When that's not possible, validate the parameters
using `validateParameter()` or `validatePassword()`.

Passwords use a less strict allowlist than other parameters (e.g. DB
names), since passwords tend to use more special characters but we can
afford to be more restrictive in the generic `validateParameter()`.

In `SQLiteDatabaseManager`, names of file-based databases are validated
(in `createDatabase`, `deleteDatabase` and `databaseExists`) using a
similar allowlist to the (non-password) parameters in other DB managers,
with an additional character: `.` (this addition is necessary since
file-based SQLite databases end with `.sqlite`).

### DatabaseTenancyBootstrapper - harden() and the lost test file

While checking for more places that could use validation, I realized
that it's possible to update tenant's db_name to the central DB or the
DB of another tenant. Added the `DatabaseTenancyBootstrapper::$harden`
property -- setting it to true prevents tenants from connecting to the
wrong databases (`RuntimeException` is thrown after connecting to the
wrong database).

Also, the DatabaseTenancyBootstrapper test file was ignored while
running tests because it lacked the `Test` suffix. Added the suffix and
fixed the broken `DATABASE_URL` test in the file.

### SQLiteDatabaseManager - respect static $path property in
makeConnectionConfig()

SQLiteDatabaseManager had a bug in `makeConnectionConfig`: the method
didn't respect the static `$path` property, it used `database_path()`
instead. Added a regression test for that. Also recognizing in-memory
SQLite databases (using `isInMemory()`) is more strict now so that
simply having a db_name with `_tenancy_inmemory_` somewhere in the name
doesn't make a file-based database considered in-memory.

### MySQLDatabaseManager - charset and collation defaulting

Creating databases with `null` charsets and collations resulted in a
`QueryException`, since null isn't a valid charset/collation. To solve
that, in the `CREATE DATABASE` statement in MySQLDatabaseManager, only
add charset/collation to the statement if they are not null.

MySQL defaults to the server's charset and collation, so it's safe to
not pass any charset/collation in the `CREATE DATABASE` statement and
let MySQL choose. Also, if e.g. collation is non-null and charset is
null, MySQL will use a charset compatible with the used collation, and
this works both ways.

---------

Co-authored-by: Samuel Stancl <samuel@archte.ch>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

tests/Bootstrappers/DatabaseTenancyBootstrapper.php

@@ -1,35 +0,0 @@
-<?php
-
-use Illuminate\Support\Facades\Event;
-use Stancl\Tenancy\Bootstrappers\DatabaseTenancyBootstrapper;
-use Stancl\Tenancy\Events\TenancyEnded;
-use Stancl\Tenancy\Events\TenancyInitialized;
-use Stancl\Tenancy\Listeners\BootstrapTenancy;
-use Stancl\Tenancy\Listeners\RevertToCentralContext;
-use Stancl\Tenancy\Tests\Etc\Tenant;
-
-use function Stancl\Tenancy\Tests\pest;
-
-beforeEach(function () {
-    Event::listen(TenancyInitialized::class, BootstrapTenancy::class);
-    Event::listen(TenancyEnded::class, RevertToCentralContext::class);
-});
-
-test('database tenancy bootstrapper throws an exception if DATABASE_URL is set', function (string|null $databaseUrl) {
-    if ($databaseUrl) {
-        config(['database.connections.central.url' => $databaseUrl]);
-
-        pest()->expectException(Exception::class);
-    }
-
-    config(['tenancy.bootstrappers' => [DatabaseTenancyBootstrapper::class]]);
-
-    $tenant1 = Tenant::create();
-
-    pest()->artisan('tenants:migrate');
-
-    tenancy()->initialize($tenant1);
-
-    expect(true)->toBe(true);
-})->with(['abc.us-east-1.rds.amazonaws.com', null]);
-

tests/Bootstrappers/DatabaseTenancyBootstrapperTest.php

@@ -0,0 +1,162 @@
+<?php
+
+use Illuminate\Support\Facades\Event;
+use Stancl\JobPipeline\JobPipeline;
+use Stancl\Tenancy\Bootstrappers\DatabaseTenancyBootstrapper;
+use Stancl\Tenancy\Events\TenancyEnded;
+use Stancl\Tenancy\Events\TenancyInitialized;
+use Stancl\Tenancy\Jobs\CreateDatabase;
+use Stancl\Tenancy\Events\TenantCreated;
+use Stancl\Tenancy\Listeners\BootstrapTenancy;
+use Stancl\Tenancy\Listeners\RevertToCentralContext;
+use Stancl\Tenancy\Tests\Etc\Tenant;
+use Illuminate\Support\Str;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Database\QueryException;
+use Stancl\Tenancy\Database\TenantDatabaseManagers\MySQLDatabaseManager;
+use Stancl\Tenancy\Database\TenantDatabaseManagers\SQLiteDatabaseManager;
+use Stancl\Tenancy\Database\TenantDatabaseManagers\PostgreSQLDatabaseManager;
+use Stancl\Tenancy\Database\TenantDatabaseManagers\PostgreSQLSchemaManager;
+
+use function Stancl\Tenancy\Tests\pest;
+
+afterEach($cleanup = function () {
+    DatabaseTenancyBootstrapper::$harden = false;
+});
+
+beforeEach(function () use ($cleanup) {
+    Event::listen(TenancyInitialized::class, BootstrapTenancy::class);
+    Event::listen(TenancyEnded::class, RevertToCentralContext::class);
+
+    $cleanup();
+});
+
+test('harden prevents tenants from using the central database', function (bool $harden, string $connection, string $manager) {
+    config([
+        'tenancy.bootstrappers' => [DatabaseTenancyBootstrapper::class],
+        "tenancy.database.managers.{$connection}" => $manager,
+    ]);
+
+    // Point the central connection at the tested connection's config and migrate it
+    // (so that the central database/schema contains the tenants table).
+    $centralConnection = config('tenancy.database.central_connection');
+    $centralConfig = config("database.connections.{$connection}");
+
+    if ($connection === 'sqlite') {
+        $centralConfig['database'] = database_path($sqliteCentralDb = 'central.sqlite');
+    }
+
+    DB::purge($centralConnection);
+    config(["database.connections.{$centralConnection}" => $centralConfig]);
+
+    pest()->artisan('migrate:fresh', [
+        '--force' => true,
+        '--path' => __DIR__ . '/../../assets/migrations',
+        '--realpath' => true,
+    ]);
+
+    DatabaseTenancyBootstrapper::$harden = $harden;
+
+    Event::listen(TenantCreated::class, JobPipeline::make([CreateDatabase::class])->send(function (TenantCreated $event) {
+        return $event->tenant;
+    })->toListener());
+
+    // Create the tenant with its own database, then repoint it at the central database/schema
+    // (which contains the tenants table that the hardening check looks for).
+    $tenant = Tenant::create(['tenancy_db_connection' => $connection]);
+
+    $central = DB::connection($centralConnection);
+    $centralName = match (true) {
+        $manager === PostgreSQLSchemaManager::class => $central->selectOne('SELECT current_schema() AS schema')->schema, // Central schema name
+        $connection === 'sqlite' => $sqliteCentralDb, // Central SQLite DB name
+        default => $central->getDatabaseName(), // Central DB name
+    };
+
+    $tenant->update(['tenancy_db_name' => $centralName]);
+
+    if ($harden) {
+        // Harden blocks initialization for tenants that use the central database
+        expect(fn () => tenancy()->initialize($tenant))->toThrow(RuntimeException::class);
+
+        // Connection should be reverted back to central
+        expect(DB::connection()->getName())->toBe($centralConnection);
+    } else {
+        expect(fn () => tenancy()->initialize($tenant))->not()->toThrow(Throwable::class);
+
+        // Connection not reverted to central
+        expect(DB::connection()->getName())->toBe('tenant');
+    }
+})->with([
+    'hardening enabled' => true,
+    'hardening disabled' => false,
+])->with('db_managers');
+
+test('harden prevents tenants from using the database of another tenant', function (bool $harden, string $connection, string $manager) {
+    config([
+        'tenancy.bootstrappers' => [DatabaseTenancyBootstrapper::class],
+        "tenancy.database.managers.{$connection}" => $manager,
+    ]);
+
+    DatabaseTenancyBootstrapper::$harden = $harden;
+
+    Event::listen(TenantCreated::class, JobPipeline::make([CreateDatabase::class])->send(function (TenantCreated $event) {
+        return $event->tenant;
+    })->toListener());
+
+    $tenant = Tenant::create(['tenancy_db_connection' => $connection]);
+
+    $dbName = Str::random(8) . ($connection === 'sqlite' ? '.sqlite' : '');
+
+    Tenant::create(['tenancy_db_name' => $dbName, 'tenancy_db_connection' => $connection]);
+
+    $tenant->update(['tenancy_db_name' => $dbName]);
+
+    if ($harden) {
+        // Harden blocks initialization for tenants that use the database of another tenant
+        expect(fn () => tenancy()->initialize($tenant))->toThrow(RuntimeException::class);
+
+        // Connection should be reverted back to central
+        expect(DB::connection()->getName())->toBe('central');
+    } else {
+        expect(fn() => tenancy()->initialize($tenant))->not()->toThrow(Throwable::class);
+
+        // Connection not reverted to central
+        expect(DB::connection()->getName())->toBe('tenant');
+    }
+})->with([
+    'hardening enabled' => true,
+    'hardening disabled' => false,
+])->with('db_managers');
+
+test('database tenancy bootstrapper throws an exception if DATABASE_URL is set', function (string|null $databaseUrl) {
+    config(['database.connections.central.url' => $databaseUrl]);
+
+    config(['tenancy.bootstrappers' => [DatabaseTenancyBootstrapper::class]]);
+
+    Event::listen(TenantCreated::class, JobPipeline::make([CreateDatabase::class])->send(function (TenantCreated $event) {
+        return $event->tenant;
+    })->toListener());
+
+    if ($databaseUrl) {
+        expect(fn() => Tenant::create())->toThrow(QueryException::class);
+    } else {
+        expect(function() {
+            $tenant1 = Tenant::create();
+
+            pest()->artisan('tenants:migrate');
+
+            tenancy()->initialize($tenant1);
+        })->not()->toThrow(Throwable::class);
+    }
+})->with(['abc.us-east-1.rds.amazonaws.com', null]);
+
+// Database managers to test with hardening.
+// Permission controlled managers omitted as they inherit the non-perm controlled managers (= they share the same code paths),
+// each important code path is covered by testing the non-permission controlled manager, so adding permission controlled managers
+// would add unnecessary complexity to the tests.
+dataset('db_managers', [
+    'mysql' => ['mysql', MySQLDatabaseManager::class],
+    'pgsql (database)' => ['pgsql', PostgreSQLDatabaseManager::class],
+    'pgsql (schema)' => ['pgsql', PostgreSQLSchemaManager::class],
+    'sqlite' => ['sqlite', SQLiteDatabaseManager::class],
+]);