fix: change config.config_data column type to longblob in mysql (#2434)

See
https://github.com/woodpecker-ci/woodpecker/pull/2418#discussion_r1320832841
for context.

server/model/config.go

@@ -30,7 +30,7 @@ type Config struct {
 	RepoID int64  `json:"-"    xorm:"UNIQUE(s) 'config_repo_id'"`
 	Hash   string `json:"hash" xorm:"UNIQUE(s) 'config_hash'"`
 	Name   string `json:"name" xorm:"config_name"`
-	Data   []byte `json:"data" xorm:"config_data"`
+	Data   []byte `json:"data" xorm:"LONGBLOB 'config_data'"`
 } //	@name Config
 
 // PipelineConfig is the n:n relation between Pipeline and Config

server/store/datastore/migration/024_config_data_type.go

@@ -0,0 +1,37 @@
+// Copyright 2023 Woodpecker Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package migration
+
+import (
+	"xorm.io/xorm"
+	"xorm.io/xorm/schemas"
+)
+
+var alterTableConfigUpdateColumnConfigDataType = task{
+	name: "alter-table-config-update-type-of-config-data",
+	fn: func(sess *xorm.Session) (err error) {
+		dialect := sess.Engine().Dialect().URI().DBType
+
+		switch dialect {
+		case schemas.MYSQL:
+			_, err = sess.Exec("ALTER TABLE config MODIFY COLUMN config_data LONGBLOB")
+		default:
+			// xorm uses the same type for all blob sizes in sqlite and postgres
+			return nil
+		}
+
+		return err
+	},
+}

server/store/datastore/migration/migration.go

@@ -56,6 +56,7 @@ var migrationTasks = []*task{
 	&addOrgs,
 	&addOrgID,
 	&alterTableTasksUpdateColumnTaskDataType,
+	&alterTableConfigUpdateColumnConfigDataType,
 }
 
 var allBeans = []interface{}{