Add some handy shortcuts for typical migration tasks

This will make it much easier for extension developers (and also less
error-prone) to create migrations for things like creating tables,
renaming columns and so on...

composer.json

@@ -26,7 +26,7 @@
         "illuminate/config": "5.1.*",
         "illuminate/container": "5.1.*",
         "illuminate/contracts": "5.1.*",
-        "illuminate/database": "5.1.*",
+        "illuminate/database": "^5.1.31",
         "illuminate/events": "5.1.*",
         "illuminate/filesystem": "5.1.*",
         "illuminate/hashing": "5.1.*",

src/Database/Migration.php

@@ -0,0 +1,95 @@
+<?php
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Database;
+
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Database\Schema\Builder;
+
+/**
+ * Migration factory.
+ *
+ * Implements some handy shortcuts for creating typical migrations.
+ */
+abstract class Migration
+{
+    /**
+     * Create a table.
+     */
+    public static function createTable($name, callable $definition)
+    {
+        return [
+            'up' => function (Builder $schema) use ($name, $definition) {
+                $schema->create($name, $definition);
+            },
+            'down' => function (Builder $schema) use ($name) {
+                $schema->drop($name);
+            }
+        ];
+    }
+
+    /**
+     * Rename a table.
+     */
+    public static function renameTable($from, $to)
+    {
+        return [
+            'up' => function (Builder $schema) use ($from, $to) {
+                $schema->rename($from, $to);
+            },
+
+            'down' => function (Builder $schema) use ($from, $to) {
+                $schema->rename($to, $from);
+            }
+        ];
+    }
+
+    /**
+     * Add columns to a table.
+     */
+    public static function addColumns($tableName, array $columnDefinitions)
+    {
+        return [
+            'up' => function (Builder $schema) use ($tableName, $columnDefinitions) {
+                $schema->table($tableName, function (Blueprint $table) use ($columnDefinitions) {
+                    foreach ($columnDefinitions as $columnName => $options) {
+                        $type = array_shift($options);
+                        $table->addColumn($type, $columnName, $options);
+                    }
+                });
+            },
+            'down' => function (Builder $schema) use ($tableName, $columnDefinitions) {
+                $schema->table($tableName, function (Blueprint $table) use ($columnDefinitions) {
+                    $table->dropColumn(array_keys($columnDefinitions));
+                });
+            }
+        ];
+    }
+
+    /**
+     * Rename a column.
+     */
+    public static function renameColumn($tableName, $from, $to)
+    {
+        return [
+            'up' => function (Builder $schema) use ($tableName, $from, $to) {
+                $schema->table($tableName, function (Blueprint $table) use ($from, $to) {
+                    $table->renameColumn($from, $to);
+                });
+            },
+
+            'down' => function (Builder $schema) use ($tableName, $from, $to) {
+                $schema->table($tableName, function (Blueprint $table) use ($from, $to) {
+                    $table->renameColumn($to, $from);
+                });
+            }
+        ];
+    }
+}