From 3e87168ec5e96ac92f9d4d8e1de1e50bde6334b6 Mon Sep 17 00:00:00 2001
From: Timo Tijhof <krinkle@fastmail.com>
Date: Thu, 6 Jul 2023 01:04:33 +0100
Subject: [PATCH] PDO: Move online schema creation behind feature flag

The XHGui install at Wikimedia Foundation is deployed with database
credentials that permit read-write operations (SELECT, INSERT) but
as safety precaution do not permit admin actions like CREATE from
individual web requests. In addition to not allowing admin actions,
our install also disallows DELETE queries, given that the install
is exposed to the public Internet (ref https://github.com/perftools/xhgui/issues/248)
and further disables POST requests (so that those features serve
HTTP 40x instead of a db query error with HTTP 50x).

Since XHGui version 0.16.0, with https://github.com/perftools/xhgui/pull/355,
the lazy-creation for tables was moved from the Saver code (which is
not used when browsing XHGui) to to Repo code, and thus resulted in
the application serving HTTP 500 on all requests, unless the
`CREATE TABLE` query is permitted on all web requests.

Fix this by making this method call feature flagged in a way that
can be disabled using XHGUI_PDO_INITSCHEMA=false.

Change-Id: I681d500fd393a47471a475b705c67280b39ab7ce
---
 config/config.default.php                  | 1 +
 src/Db/PdoRepository.php                   | 1 -
 src/ServiceProvider/PdoStorageProvider.php | 6 +++++-
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/config/config.default.php b/config/config.default.php
index 9d6a49c6..e7e8c035 100644
--- a/config/config.default.php
+++ b/config/config.default.php
@@ -18,6 +18,7 @@
         'pass' => getenv('XHGUI_PDO_PASS') ?: null,
         'table' => getenv('XHGUI_PDO_TABLE') ?: 'results',
         'tableWatch' => getenv('XHGUI_PDO_TABLE_WATCHES') ?: 'watches',
+        'initSchema' => getenv('XHGUI_PDO_INITSCHEMA') ?: 'true',
     ],
 
     // Database options for MongoDB.
diff --git a/src/Db/PdoRepository.php b/src/Db/PdoRepository.php
index abbb8e55..5d1f48f6 100644
--- a/src/Db/PdoRepository.php
+++ b/src/Db/PdoRepository.php
@@ -34,7 +34,6 @@ public function __construct(PDO $pdo, string $driverName, string $table, string
         $this->driverName = $driverName;
         $this->table = sprintf('"%s"', $table);
         $this->tableWatches = sprintf('"%s"', $tableWatch);
-        $this->initSchema();
     }
 
     public function getLatest(): array
diff --git a/src/ServiceProvider/PdoStorageProvider.php b/src/ServiceProvider/PdoStorageProvider.php
index 2e1f0cea..2ac7ffd5 100644
--- a/src/ServiceProvider/PdoStorageProvider.php
+++ b/src/ServiceProvider/PdoStorageProvider.php
@@ -48,12 +48,16 @@ public function register(Container $app): void
         };
 
         $app[PdoRepository::class] = static function ($app) {
-            return new PdoRepository(
+            $repo = new PdoRepository(
                 $app['pdo'],
                 $app['pdo.driver'],
                 $app['config']['pdo']['table'],
                 $app['config']['pdo']['tableWatch']
             );
+            if ($app['config']['pdo']['initSchema'] === 'true') {
+                $repo->initSchema();
+            }
+            return $repo;
         };
 
         $app['searcher.pdo'] = static function ($app) {