From 703a6dd039a184a5524325f05ce78ca08d8ef403 Mon Sep 17 00:00:00 2001
From: Ariel Mashraki <mashraki@fb.com>
Date: Wed, 20 Nov 2019 09:47:48 -0800
Subject: [PATCH] dialect/sql/schema: mysql support for uuid type

Summary: Pull Request resolved: https://github.com/facebookincubator/ent/pull/176

Reviewed By: alexsn

Differential Revision: D18615992

fbshipit-source-id: 2c86a661e8d75165470b9b2d351cb973147290d8
---
 .golangci.yml                    |  2 +-
 dialect/sql/schema/mysql.go      | 14 ++++++++++++++
 dialect/sql/schema/mysql_test.go |  7 +++++--
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/.golangci.yml b/.golangci.yml
index 310a13778..79481942e 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -8,7 +8,7 @@ linters-settings:
     threshold: 100
   funlen:
     lines: 100
-    statements: 70
+    statements: 80
 
 linters:
   disable-all: true
diff --git a/dialect/sql/schema/mysql.go b/dialect/sql/schema/mysql.go
index 8dbae3fb9..57e1f0fe0 100644
--- a/dialect/sql/schema/mysql.go
+++ b/dialect/sql/schema/mysql.go
@@ -190,6 +190,8 @@ func (d *MySQL) cType(c *Column) (t string) {
 		}
 		sort.Strings(values)
 		t = fmt.Sprintf("enum(%s)", strings.Join(values, ", "))
+	case field.TypeUUID:
+		t = "char(36) binary"
 	default:
 		panic(fmt.Sprintf("unsupported type %q for column %q", c.Type.String(), c.Name))
 	}
@@ -306,6 +308,18 @@ func (d *MySQL) scanColumn(c *Column, rows *sql.Rows) error {
 		for i, e := range parts[1:] {
 			c.Enums[i] = strings.Trim(e, "'")
 		}
+	case "char":
+		size, err := strconv.ParseInt(parts[1], 10, 64)
+		if err != nil {
+			return fmt.Errorf("converting char size to int: %v", err)
+		}
+		// UUID field has length of 36 characters (32 alphanumeric characters and 4 hyphens).
+		if size != 36 {
+			return fmt.Errorf("unknown char(%d) type (not a uuid)", size)
+		}
+		c.Type = field.TypeUUID
+	default:
+		return fmt.Errorf("unknown column type %q for version %q", parts[0], d.version)
 	}
 	if defaults.Valid {
 		return c.ScanDefault(defaults.String)
diff --git a/dialect/sql/schema/mysql_test.go b/dialect/sql/schema/mysql_test.go
index dcff0bd8e..b37b8f788 100644
--- a/dialect/sql/schema/mysql_test.go
+++ b/dialect/sql/schema/mysql_test.go
@@ -56,6 +56,7 @@ func TestMySQL_Create(t *testing.T) {
 						{Name: "age", Type: field.TypeInt},
 						{Name: "doc", Type: field.TypeJSON, Nullable: true},
 						{Name: "enums", Type: field.TypeEnum, Enums: []string{"a", "b"}},
+						{Name: "uuid", Type: field.TypeUUID, Nullable: true},
 					},
 				},
 			},
@@ -66,7 +67,7 @@ func TestMySQL_Create(t *testing.T) {
 				mock.ExpectQuery(escape("SELECT COUNT(*) FROM INFORMATION_SCHEMA.TABLES WHERE `TABLE_SCHEMA` = (SELECT DATABASE()) AND `TABLE_NAME` = ?")).
 					WithArgs("users").
 					WillReturnRows(sqlmock.NewRows([]string{"count"}).AddRow(0))
-				mock.ExpectExec(escape("CREATE TABLE IF NOT EXISTS `users`(`id` bigint AUTO_INCREMENT NOT NULL, `name` varchar(255) NULL, `age` bigint NOT NULL, `doc` json NULL, `enums` enum('a', 'b') NOT NULL, PRIMARY KEY(`id`)) CHARACTER SET utf8mb4")).
+				mock.ExpectExec(escape("CREATE TABLE IF NOT EXISTS `users`(`id` bigint AUTO_INCREMENT NOT NULL, `name` varchar(255) NULL, `age` bigint NOT NULL, `doc` json NULL, `enums` enum('a', 'b') NOT NULL, `uuid` char(36) binary NULL, PRIMARY KEY(`id`)) CHARACTER SET utf8mb4")).
 					WillReturnResult(sqlmock.NewResult(0, 1))
 				mock.ExpectCommit()
 			},
@@ -166,6 +167,7 @@ func TestMySQL_Create(t *testing.T) {
 						{Name: "id", Type: field.TypeInt, Increment: true},
 						{Name: "name", Type: field.TypeString, Nullable: true},
 						{Name: "text", Type: field.TypeString, Nullable: true, Size: math.MaxInt32},
+						{Name: "uuid", Type: field.TypeUUID, Nullable: true},
 						{Name: "age", Type: field.TypeInt},
 					},
 					PrimaryKey: []*Column{
@@ -185,7 +187,8 @@ func TestMySQL_Create(t *testing.T) {
 					WillReturnRows(sqlmock.NewRows([]string{"column_name", "column_type", "is_nullable", "column_key", "column_default", "extra", "character_set_name", "collation_name"}).
 						AddRow("id", "bigint(20)", "NO", "PRI", "NULL", "auto_increment", "", "").
 						AddRow("name", "varchar(255)", "YES", "YES", "NULL", "", "", "").
-						AddRow("text", "longtext", "YES", "YES", "NULL", "", "", ""))
+						AddRow("text", "longtext", "YES", "YES", "NULL", "", "", "").
+						AddRow("uuid", "char(36)", "YES", "YES", "NULL", "", "", "utf8mb4_bin"))
 				mock.ExpectQuery(escape("SELECT `index_name`, `column_name`, `non_unique`, `seq_in_index` FROM INFORMATION_SCHEMA.STATISTICS WHERE `TABLE_SCHEMA` = (SELECT DATABASE()) AND `TABLE_NAME` = ?")).
 					WithArgs("users").
 					WillReturnRows(sqlmock.NewRows([]string{"index_name", "column_name", "non_unique", "seq_in_index"}).