From c7f043b589959b365c88f7b9e404083d3075491d Mon Sep 17 00:00:00 2001
From: Ben Johnson <bjohnson@subsplash.com>
Date: Tue, 20 Aug 2019 15:50:33 -0700
Subject: [PATCH] Added support for migrations with comments (mysql only)

---
 gomigrate.go                              | 13 +++++++++++++
 test_migrations/test1_mysql/1_test_up.sql |  4 ++++
 2 files changed, 17 insertions(+)

diff --git a/gomigrate.go b/gomigrate.go
index 09ecd52..73a4059 100644
--- a/gomigrate.go
+++ b/gomigrate.go
@@ -10,6 +10,7 @@ import (
 	"os"
 	"path/filepath"
 	"sort"
+	"strings"
 )
 
 type migrationType string
@@ -238,6 +239,18 @@ func (m *Migrator) ApplyMigration(migration *Migration, mType migrationType) err
 
 	// Perform the migration.
 	for _, cmd := range commands {
+		cmd = strings.ReplaceAll(cmd, "\n", "") // strip off leading whitespace
+		if strings.HasPrefix(cmd, "SELECT") && strings.HasSuffix(cmd, "AS comment") {
+			row := transaction.QueryRow(cmd)
+			var comment string
+			err = row.Scan(&comment)
+			if err != nil {
+				m.logger.Printf("Error executing query comment: %v", err)
+				return err
+			}
+			m.logger.Printf("Comment: %v", comment)
+			continue
+		}
 		result, err := transaction.Exec(cmd)
 		if err != nil {
 			m.logger.Printf("Error executing migration: %v", err)
diff --git a/test_migrations/test1_mysql/1_test_up.sql b/test_migrations/test1_mysql/1_test_up.sql
index 5e504d5..f56d3b0 100644
--- a/test_migrations/test1_mysql/1_test_up.sql
+++ b/test_migrations/test1_mysql/1_test_up.sql
@@ -3,11 +3,15 @@ CREATE TABLE test (
      PRIMARY KEY (id)
 );
 
+SELECT 'my comment' AS comment;
+
 CREATE TABLE test2 (
      id INT NOT NULL AUTO_INCREMENT,
      PRIMARY KEY (id)
 );
 
+SELECT 'my other comment' AS comment;
+
 CREATE TABLE tt (c text NOT NULL);
 
 INSERT INTO tt VALUES('a');