More helpful messages on db connection failures (#17789)

* Added a message map to allow translating db error messages

* Allow translation of db error message

* Also include mysql error numbers as possible detection mechanisms for errors

* Only create a new exception if we're changing the message

* Missed change

* Fixing tests

* More test fixes

* Update en.json

Use MySQL server has gone away to help people google the fix

5 files changed, 54 insertions, 11 deletions

diff --git a/core/Db/Adapter.php b/core/Db/Adapter.php
index 7beccd9c24..44263a9f50 100644
--- a/core/Db/Adapter.php
+++ b/core/Db/Adapter.php
@@ -9,6 +9,7 @@
 namespace Piwik\Db;
 
 use Zend_Db_Table;
+use Piwik\Piwik;
 
 /**
  */
@@ -45,14 +46,24 @@ class Adapter
             $infos[$key] = $val;
         }
 
-        $adapter   = new $className($infos);
+        $adapter = new $className($infos);
 
         if ($connect) {
-            $adapter->getConnection();
-
-            Zend_Db_Table::setDefaultAdapter($adapter);
-            // we don't want the connection information to appear in the logs
-            $adapter->resetConfig();
+            try {
+                $adapter->getConnection();
+
+                Zend_Db_Table::setDefaultAdapter($adapter);
+                // we don't want the connection information to appear in the logs
+                $adapter->resetConfig();
+            } catch(\Exception $e) {
+                // we don't want certain exceptions to leak information
+                $msg = self::overriddenExceptionMessage($e->getMessage());
+                if ('' !== $msg) {
+                    throw new \Exception($msg);
+                }
+
+                throw $e;
+            }
         }
 
         return $adapter;
@@ -129,4 +140,28 @@ class Adapter
     {
         return strtolower($adapterName) === 'pdo/mysql';
     }
+
+    /**
+     * Intercepts certain exception messages and replaces leaky ones with ones that don't reveal too much info
+     * @param string $message
+     * @return string
+     */
+    public static function overriddenExceptionMessage($message)
+    {
+        $safeMessageMap = array(
+            // add any exception search terms and their replacement message here
+            '[2006]'                        => Piwik::translate('General_ExceptionDatabaseUnavailable'),
+            'MySQL server has gone away'    => Piwik::translate('General_ExceptionDatabaseUnavailable'),
+            '[1698]'                        => Piwik::translate('General_ExceptionDatabaseAccess'),
+            'Access denied'                 => Piwik::translate('General_ExceptionDatabaseAccess')
+        );
+
+        foreach ($safeMessageMap as $search_term => $safeMessage) {
+            if (strpos($message, $search_term) !== false) {
+                return $safeMessage;
+            }
+        }
+
+        return '';
+    }
 }
diff --git a/lang/en.json b/lang/en.json
index f71889a9b1..de2344a89f 100644
--- a/lang/en.json
+++ b/lang/en.json
@@ -177,6 +177,8 @@
         "ExceptionDatabaseVersion": "Your %1$s version is %2$s but Matomo requires at least %3$s.",
         "ExceptionDatabaseVersionNewerThanCodebase": "Your Matomo codebase is running the old version %1$s and we have detected that your Matomo Database has already been upgraded to the newer version %2$s.",
         "ExceptionDatabaseVersionNewerThanCodebaseWait": "Maybe your Matomo administrators are currently finishing the upgrade process. Please try again in a few minutes.",
+        "ExceptionDatabaseUnavailable": "MySQL server has gone away",
+        "ExceptionDatabaseAccess": "Database access denied",
         "ExceptionFileIntegrity": "Integrity check failed: %s",
         "ExceptionFilesizeMismatch": "File size mismatch: %1$s (expected length: %2$s, found: %3$s)",
         "ExceptionIncompatibleClientServerVersions": "Your %1$s client version is %2$s which is incompatible with server version %3$s.",
diff --git a/plugins/Installation/tests/System/APITest.php b/plugins/Installation/tests/System/APITest.php
index faca839ee0..370b99e3bc 100644
--- a/plugins/Installation/tests/System/APITest.php
+++ b/plugins/Installation/tests/System/APITest.php
@@ -47,7 +47,7 @@ class APITest extends SystemTestCase
         $data = str_replace("\n", "", $response['data']);
 
         $this->assertStringStartsWith('<?xml version="1.0" encoding="utf-8" ?><result>	<error message=', $data);
-        self::assertStringContainsString('Access denied', $data);
+        self::assertStringContainsString('Database access denied', $data);
         $this->assertStringEndsWith('</result>', $data);
     }
 
@@ -58,7 +58,7 @@ class APITest extends SystemTestCase
         $data = str_replace("\n", "", $response['data']);
 
         $this->assertStringStartsWith('{"result":"error","message":"', $data);
-        self::assertStringContainsString('Access denied', $data);
+        self::assertStringContainsString('Database access denied', $data);
     }
 
     public function test_shouldReturnEmptyResultWhenNotInstalledAndDispatchIsDisabled()
diff --git a/tests/PHPUnit/Unit/Tracker/CacheTest.php b/tests/PHPUnit/Unit/Tracker/CacheTest.php
index 145cd56004..0408cff6d6 100644
--- a/tests/PHPUnit/Unit/Tracker/CacheTest.php
+++ b/tests/PHPUnit/Unit/Tracker/CacheTest.php
@@ -54,7 +54,7 @@ class CacheTest extends UnitTestCase
     public function provideContainerConfig()
     {
         $mockLazyCache = $this->getMockBuilder(Lazy::class)
-            ->onlyMethods(['flushAll', 'delete'])
+            ->onlyMethods(['flushAll', 'fetch', 'save', 'delete'])
             ->disableOriginalConstructor()
             ->getMock();
         $mockLazyCache
@@ -64,6 +64,12 @@ class CacheTest extends UnitTestCase
         $mockLazyCache->method('delete')->willReturnCallback(function ($key) {
                 $this->methodsCalled[] = 'delete.' . $key;
             });
+        $mockLazyCache->method('save')->willReturnCallback(function ($id, $data) {
+            $this->methodsCalled[] = 'save.' . $id . $data;
+        });
+        $mockLazyCache->method('fetch')->willReturnCallback(function ($id) {
+            $this->methodsCalled[] = 'fetch.' . $id;
+        });
 
         return [
             Lazy::class => $mockLazyCache,
diff --git a/tests/UI/expected-screenshots/UIIntegrationTest_db_connect_error.png b/tests/UI/expected-screenshots/UIIntegrationTest_db_connect_error.png
index 066a46245c..952dc6e7d6 100644
--- a/tests/UI/expected-screenshots/UIIntegrationTest_db_connect_error.png
+++ b/tests/UI/expected-screenshots/UIIntegrationTest_db_connect_error.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:1c66b67f954aaa21a5ef577189220cd2018e210cdbbda219a9af0adae1698634
-size 75052
+oid sha256:67b00cbec9103edce15aee9ba01ff977f285063434b5d9f6dba66efc0fb407e5
+size 62482