Handle PostgreSQL connection errors

lib/AbstractException.php

@@ -26,6 +26,7 @@ abstract class AbstractException extends \Exception {
         "Db/Exception.fileUnwritable"                 => 10205,
         "Db/Exception.fileUncreatable"                => 10206,
         "Db/Exception.fileCorrupt"                    => 10207,
+        "Db/Exception.connectionFailure"              => 10208,
         "Db/Exception.updateTooNew"                   => 10211,
         "Db/Exception.updateManual"                   => 10212,
         "Db/Exception.updateManualOnly"               => 10213,

lib/Db/PostgreSQL/PDODriver.php

@@ -22,10 +22,22 @@ class PDODriver extends Driver {
 
     protected function makeConnection(string $user, string $pass, string $db, string $host, int $port, string $service) {
         $dsn = $this->makeconnectionString(true, $user, $pass, $db, $host, $port, $service);
+        try {
             $this->db = new \PDO("pgsql:$dsn", $user, $pass, [
                 \PDO::ATTR_ERRMODE => \PDO::ERRMODE_EXCEPTION,
                 \PDO::ATTR_PERSISTENT => true,
             ]);
+        } catch (\PDOException $e) {
+            if ($e->getCode() == 7) {
+                switch (substr($e->getMessage(), 9, 5)) {
+                    case "08006":
+                        throw new Exception("connectionFailure", ["PostgreSQL", substr($e->getMessage(), 28)]);
+                    default:
+                        throw $e; // @codeCoverageIgnore
+                }
+            }
+            throw $e; // @codeCoverageIgnore
+        }
     }
 
     public function __destruct() {

locale/en.php

@@ -122,6 +122,7 @@ return [
     'Exception.JKingWeb/Arsse/Db/Exception.fileUnusable'                   => 'Insufficient permissions to open database file "{0}" for reading or writing',
     'Exception.JKingWeb/Arsse/Db/Exception.fileUncreatable'                => 'Insufficient permissions to create new database file "{0}"',
     'Exception.JKingWeb/Arsse/Db/Exception.fileCorrupt'                    => 'Database file "{0}" is corrupt or not a valid database',
+    'Exception.JKingWeb/Arsse/Db/Exception.connectionFailure'              => 'Could not connect to {0} database: {1}',
     'Exception.JKingWeb/Arsse/Db/Exception.paramTypeInvalid'               => 'Prepared statement parameter type "{0}" is invalid',
     'Exception.JKingWeb/Arsse/Db/Exception.paramTypeUnknown'               => 'Prepared statement parameter type "{0}" is valid, but not implemented',
     'Exception.JKingWeb/Arsse/Db/Exception.paramTypeMissing'               => 'Prepared statement parameter type for parameter #{0} was not specified',

tests/cases/Db/PostgreSQL/TestCreation.php

@@ -7,11 +7,11 @@ declare(strict_types=1);
 namespace JKingWeb\Arsse\TestCase\Db\PostgreSQL;
 
 use JKingWeb\Arsse\Arsse;
-use JKingWeb\Arsse\Db\PostgreSQL\Driver;
+use JKingWeb\Arsse\Db\PostgreSQL\PDODriver as Driver;
 
 /**
  * @group slow
- * @covers \JKingWeb\Arsse\Db\PostgreSQL\Driver<extended> */
+ * @covers \JKingWeb\Arsse\Db\PostgreSQL\PDODriver<extended> */
 class TestCreation extends \JKingWeb\Arsse\Test\AbstractTest {
     /** @dataProvider provideConnectionStrings */
     public function testGenerateConnectionString(bool $pdo, string $user, string $pass, string $db, string $host, int $port, string $service, string $exp) {
@@ -55,4 +55,13 @@ class TestCreation extends \JKingWeb\Arsse\Test\AbstractTest {
             [true,  "T'Pau of Vulcan", "superman", "datumbase", "somehost",  2112, "arsse", "service='arsse'"],
         ];
     }
+
+    public function testFailToConnect() {
+        // PDO dies not distinguish between different connection failure modes
+        self::setConf([
+            'dbPostgreSQLPass' => (string) rand(),
+        ]);
+        $this->assertException("connectionFailure", "Db");
+        new Driver;
+    }
 }