Compute hashes of executable files when migrating

The 'hash' column was added to executable_file in commit bc1608f
(Add hash to executable files and immutable executables., 2021-03-30),
but the hashes were not computed for existing files. This broke
migrations from DOMjudge 7.x (judgehost error "Fetching executable
failed for compile script '<id>': Unexpected hash ...").

This commit fixes Version20210407120356.php (populate immutable
executable tables) so that it will compute the hashes, and also adds a
new migration to compute the hashes for databases that have already
been migrated from 7.x to 8.x.

This commit also re-runs migration Version20230508163415.php (update
hashes of immutable executables), because that migration uses the
hashes of the individual executable files. This is achieved by moving
that code to a new file (Version20230508180000.php) and converting the
original file to a no-op (we don't delete it to prevent warnings about
previously executed migrations that are not registered). This
automatically fixes the hashes of immutable executable in databases
migrated from 7.x to a DOMjudge version containing the original file
(8.2.1, 8.2.2, 8.2.3, and 8.3.0).

Author: tom93

webapp/migrations/Version20210407120356.php

@@ -53,9 +53,9 @@ public function up(Schema $schema) : void
                     }
                     $this->connection->executeStatement(
                         'INSERT INTO executable_file '
-                        . '(`immutable_execid`, `filename`, `ranknumber`, `file_content`, `is_executable`) '
+                        . '(`immutable_execid`, `filename`, `ranknumber`, `file_content`, `hash`, `is_executable`) '
                         . 'VALUES (' . $immutable_execid . ', "' . $filename . '", '
-                        . $idx . ', ' . $encodedContent . ', '
+                        . $idx . ', ' . $encodedContent . ', "' . md5($content) . '", '
                         . $executableBit . ')'
                     );
                 }

webapp/migrations/Version20230508163415.php

@@ -4,48 +4,28 @@
 
 namespace DoctrineMigrations;
 
-use App\Entity\ExecutableFile;
 use Doctrine\DBAL\Schema\Schema;
 use Doctrine\Migrations\AbstractMigration;
 
-/**
- * Auto-generated Migration: Please modify to your needs!
- */
 final class Version20230508163415 extends AbstractMigration
 {
+    // The code that was in this file was moved to Version20230508180000.php so
+    // that it will re-run after Version20230508170000.php. This file has been
+    // kept as a no-op to prevent warnings about previously executed migrations
+    // that are not registered.
+
     public function getDescription(): string
     {
-        return 'Update hashes of immutable executables';
+        return '[Deleted]';
     }
 
     public function up(Schema $schema): void
     {
-        $immutableExecutables = $this->connection->fetchAllAssociative('SELECT immutable_execid FROM immutable_executable');
-        foreach ($immutableExecutables as $immutableExecutable) {
-            $files = $this->connection->fetchAllAssociative('SELECT hash, filename, is_executable FROM executable_file WHERE immutable_execid = :id', ['id' => $immutableExecutable['immutable_execid']]);
-            uasort($files, fn(array $a, array $b) => strcmp($a['filename'], $b['filename']));
-            $newHash = md5(
-                join(
-                    array_map(
-                        fn(array $file) => $file['hash'] . $file['filename'] . (bool)$file['is_executable'],
-                        $files
-                    )
-                )
-            );
-            $this->connection->executeQuery('UPDATE immutable_executable SET hash = :hash WHERE immutable_execid = :id', [
-                'hash' => $newHash,
-                'id' => $immutableExecutable['immutable_execid'],
-            ]);
-        }
+        $this->addSql('-- no-op'); // suppress warning "Migration <name> was executed but did not result in any SQL statements."
     }
 
     public function down(Schema $schema): void
     {
-        // We don't handle this case
-    }
-
-    public function isTransactional(): bool
-    {
-        return false;
+        $this->addSql('-- no-op');
     }
 }

webapp/migrations/Version20230508170000.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20230508170000 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Compute hashes of executable files';
+        // This migration is only required for databases that were migrated
+        // from DOMjudge 7.x using certain DOMjudge versions in the range 8.0.0
+        // to 8.3.0. Databases migrated from 7.x straight to 8.3.1+ will have
+        // the hashes computed by Version20201219154651.php.
+    }
+
+    public function up(Schema $schema): void
+    {
+        $executableFiles = $this->connection->fetchAllAssociative('SELECT execfileid, file_content FROM executable_file WHERE hash IS NULL');
+        foreach ($executableFiles as $file) {
+            $this->addSql('UPDATE executable_file SET hash = :hash WHERE execfileid = :id', [
+                'hash' => md5($file['file_content']),
+                'id' => $file['execfileid']
+            ]);
+        }
+    }
+
+    public function down(Schema $schema): void
+    {
+        // We don't handle this case
+    }
+
+    public function isTransactional(): bool
+    {
+        return false;
+    }
+}

webapp/migrations/Version20230508180000.php

@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use App\Entity\ExecutableFile;
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+/**
+ * Auto-generated Migration: Please modify to your needs!
+ */
+final class Version20230508180000 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Update hashes of immutable executables';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $immutableExecutables = $this->connection->fetchAllAssociative('SELECT immutable_execid FROM immutable_executable');
+        foreach ($immutableExecutables as $immutableExecutable) {
+            $files = $this->connection->fetchAllAssociative('SELECT hash, filename, is_executable FROM executable_file WHERE immutable_execid = :id', ['id' => $immutableExecutable['immutable_execid']]);
+            uasort($files, fn(array $a, array $b) => strcmp($a['filename'], $b['filename']));
+            $newHash = md5(
+                join(
+                    array_map(
+                        fn(array $file) => $file['hash'] . $file['filename'] . (bool)$file['is_executable'],
+                        $files
+                    )
+                )
+            );
+            $this->connection->executeQuery('UPDATE immutable_executable SET hash = :hash WHERE immutable_execid = :id', [
+                'hash' => $newHash,
+                'id' => $immutableExecutable['immutable_execid'],
+            ]);
+        }
+    }
+
+    public function down(Schema $schema): void
+    {
+        // We don't handle this case
+    }
+
+    public function isTransactional(): bool
+    {
+        return false;
+    }
+}