feat(ptosc-auto-defaults): Option to automatically add default to com…

README.md

@@ -88,6 +88,8 @@ class MyColumnWithFkMigration extends Migration
   - Adding unique indexes may cause data loss unless tables are manually checked
     beforehand [because of how PTOSC works](https://www.percona.com/doc/percona-toolkit/LATEST/pt-online-schema-change.html#id7)
   - Adding not-null columns [requires a default](https://www.percona.com/doc/percona-toolkit/LATEST/pt-online-schema-change.html#cmdoption-pt-online-schema-change-alter)
+    so this package will automatically add default to new columns
+    - See `ptosc-auto-defaults` in `config/online-migrator.php` for more.
   - Renaming a column or dropping a primary key [have additional risks](https://www.percona.com/doc/percona-toolkit/LATEST/pt-online-schema-change.html#id1)
   - Foreign key creation should be done separately from column creation or
     duplicate indexes may be created with slightly different naming

config/online-migrator.php

@@ -9,8 +9,8 @@
     | When not specified it will use the on-line capabilities; except for DBs
     | with 'test' in their name.
     |
-    | '0' bypasses any on-line tools and sends queries unchanged.
-    | '1' (or any truthy value) forces use of the on-line tools.
+    | `0` bypasses any on-line tools and sends queries unchanged.
+    | `1` (or any truthy value) forces use of the on-line tools.
     |
     */
 
@@ -34,7 +34,7 @@
 
     /*
     |--------------------------------------------------------------------------
-    | Percona Online Schema Change Options
+    | Percona Online Schema Change - Options
     |--------------------------------------------------------------------------
     |
     | Accepts a comma-separated list of options for pt-online-schema-change.
@@ -48,4 +48,23 @@
     */
 
     'ptosc-options' => env('PTOSC_OPTIONS'),
+
+    /*
+    |--------------------------------------------------------------------------
+    | Automatic Defaults For Percona Online Schema Change
+    |--------------------------------------------------------------------------
+    |
+    | Whether or not to automatically add defaults to not-null columns. Doing
+    | so works around the not-null-default requirement of PTOSC using defaults
+    | similar to what Mysql would use in non-strict mode.
+    |
+    | INTEGER: 0
+    | DATETIME: '0001-01-01 00:00:00'
+    |
+    | Set this to `false` if you prefer your migrations explicitly assign
+    | defaults as needed.
+    |
+    */
+
+    'ptosc-auto-defaults' => env('PTOSC_AUTO_DEFAULTS', true),
 ];

src/Strategy/PtOnlineSchemaChange.php

@@ -12,6 +12,22 @@
 
 class PtOnlineSchemaChange implements StrategyInterface
 {
+    /** Mimicking non-strict defaults as closely as practical. */
+    private const AUTO_DEFAULTS = [
+        'boolean' => 'FALSE',
+        'char' => "''",
+        'date' => "'0001-01-01'",
+        'datetime' => "'0001-01-01 00:00:00'",
+        'decimal' => '0.0',
+        'double' => '0.0',
+        'int' => '0',
+        'numeric' => '0.0',
+        // Text cannot have a default unless non-strict mode.
+        'time' => "'00:00:00'",
+        'timestamp' => "'1970-01-01 00:00:01'",
+        'varchar' => "''",
+    ];
+
     /**
      * Get query or command, converting "ALTER TABLE " statements to on-line commands/queries.
      *
@@ -57,6 +73,12 @@ public static function getQueryOrCommand(array &$query, Connection $connection)
                 ["default '0'", "default '1'"],
                 ['default 0', 'default 1'], $changes);
 
+            if (! empty($alter_parts)
+                && config('online-migrator.ptosc-auto-defaults')
+            ) {
+                $changes = static::getChangesWithAutoDefaults($changes);
+            }
+
             // TODO: Fix dropping FKs by prefixing constraint name with '_' or
             // '__' if already starts with '_' (quirk in PTOSC).
 
@@ -95,6 +117,38 @@ public static function getQueryOrCommand(array &$query, Connection $connection)
         return $query_or_command_str;
     }
 
+    private static function getChangesWithAutoDefaults(string $raw_changes) : string
+    {
+        $changes = [];
+
+        // Cannot do simple comma split because of types like "double(10, 5)".
+        // CONSIDER: More robust parsing for split.
+        foreach (preg_split('/,\s+(?!\d+\))/iu', $raw_changes) as $raw_change) {
+            $change = $raw_change;
+            // CONSIDER: Detecting column changes and auto-appending default
+            // when changed from nullable to not-null and doesn't have default.
+            if (preg_match('/\A\s*ADD\s+(COLUMN\s+)?`?[^`\s+]+`?\s+([^`\s+]+)(.*?\bNOT\s+NULL\b.*)/imu', $change, $add_parts)
+                && ! preg_match('/\bDEFAULT\s+[^\s]+\b/imu', $add_parts[3])
+            ) {
+                $column_type = strtolower(
+                    trim(
+                        preg_replace(
+                            '/(^BIG|^MEDIUM|^SMALL|^TINY|(INT)EGER|\(.*$)/iu',
+                            '\2',
+                            $add_parts[2]
+                        )
+                    )
+                );
+                if (isset(static::AUTO_DEFAULTS[$column_type])) {
+                    $change .= ' DEFAULT ' . static::AUTO_DEFAULTS[$column_type];
+                }
+            }
+            $changes[] = $change;
+        }
+
+        return implode(', ', $changes);
+    }
+
     /**
      * Get options from env. since artisan migrate has fixed arguments.
      *

tests/PtOnlineSchemaChangeTest.php

@@ -30,6 +30,23 @@ public function test_migrate_addsColumn()
         $this->assertEquals('green', $test_row_one->color);
     }
 
+    public function test_migrate_addsColumnsNotNullWithNoDefaults()
+    {
+        $this->loadMigrationsFrom(__DIR__ . '/migrations/adds-columns-not-null-no-defaults');
+
+        $test_row_one = \DB::table('test_om')->where('id', 1)->first();
+        $this->assertNotNull($test_row_one);
+        $this->assertEquals(false, $test_row_one->boolean_no_default);
+        $this->assertEquals('0001-01-01', $test_row_one->date_no_default);
+        $this->assertEquals('0001-01-01 00:00:00', $test_row_one->datetime_no_default);
+        $this->assertEquals(0.0, $test_row_one->float_no_default);
+        $this->assertEquals(0, $test_row_one->integer_no_default);
+        $this->assertEquals('', $test_row_one->string_no_default);
+        $this->assertEquals('00:00:00', $test_row_one->time_no_default);
+        $this->assertEquals('1970-01-01 00:00:01', $test_row_one->timestamp_no_default);
+        $this->assertEquals('', $test_row_one->uuid_no_default);
+    }
+
     public function test_migrate_addsUnique()
     {
         $this->loadMigrationsFrom(__DIR__ . '/migrations/adds-unique');
@@ -39,6 +56,7 @@ public function test_migrate_addsUnique()
         \DB::table('test_om')->insert(['name' => 'one']);
     }
 
+    /* TODO: Move to test class with ptosc-auto-defaults is false or remove
     public function test_migrate_addsWithoutDefault()
     {
         // Known to be unsupported by PTOSC (v3) for the time being, so this
@@ -48,6 +66,7 @@ public function test_migrate_addsWithoutDefault()
         $this->expectExceptionCode(getenv('TRAVIS') ? 255 : 29);
         $this->loadMigrationsFrom(__DIR__ . '/migrations/adds-without-default');
     }
+    */
 
     public function test_migrate_changesType()
     {

tests/migrations/adds-columns-not-null-no-defaults/0000_00_00_000001_add_columns_not_null_to_test_om.php

@@ -0,0 +1,35 @@
+<?php
+
+class AddColumnsNotNullToTestOm extends \Illuminate\Database\Migrations\Migration
+{
+    public function up()
+    {
+        Schema::table('test_om', function (\Illuminate\Database\Schema\Blueprint $table) {
+            // Excluding explicit defaults to test auto-defaults w/PTSOC.
+            $table->boolean('boolean_no_default')->nullable(false);
+            $table->date('date_no_default')->nullable(false);
+            $table->dateTime('datetime_no_default')->nullable(false);
+            $table->float('float_no_default')->nullable(false);
+            $table->integer('integer_no_default')->nullable(false);
+            $table->string('string_no_default')->nullable(false);
+            $table->time('time_no_default')->nullable(false);
+            $table->timestamp('timestamp_no_default')->nullable(false);
+            $table->uuid('uuid_no_default')->nullable(false);
+        });
+    }
+
+    public function down()
+    {
+        Schema::table('test_om', function (\Illuminate\Database\Schema\Blueprint $table) {
+            $table->dropColumn('boolean_no_default');
+            $table->dropColumn('date_no_default');
+            $table->dropColumn('datetime_no_default');
+            $table->dropColumn('float_no_default');
+            $table->dropColumn('integer_no_default');
+            $table->dropColumn('string_no_default');
+            $table->dropColumn('time_no_default');
+            $table->dropColumn('timestamp_no_default');
+            $table->dropColumn('uuid_no_default');
+        });
+    }
+}