models/actions/run_job.go

@@ -40,7 +40,9 @@ type ActionRunJob struct {
 
 	// WorkflowPayload is act/jobparser.SingleWorkflow for act/jobparser.Parse
 	// it should contain exactly one job with global workflow fields for this model
-	WorkflowPayload []byte
+	// MEDIUMBLOB: an untyped []byte maps to a 64 KiB BLOB on MySQL/MariaDB; large
+	// single-job workflows overflow it and InsertRun fails (see migration 371).
+	WorkflowPayload []byte `xorm:"MEDIUMBLOB"`
 
 	JobID  string   `xorm:"VARCHAR(255)"` // job id in workflow, not job's id
 	Needs  []string `xorm:"JSON TEXT"`

models/migrations/migrations.go

@@ -448,6 +448,7 @@ func prepareMigrationTasks() []*migration {
 		newMigration(368, "Drop org from repo manifest (derived from org profile)", v1_27.DropOrgFromRepoManifest),
 		newMigration(369, "Rename mokogitea-actions system user to mokogit-actions", v1_27.RenameActionsUserToMokoGit),
 		newMigration(370, "Remap saved gitea-* user themes to mokogit-*", v1_27.RemapGiteaThemesToMokogit),
+		newMigration(371, "Widen action_run_job.workflow_payload to MEDIUMBLOB", v1_27.WidenActionRunJobWorkflowPayload),
 	}
 	return preparedMigrations
 }

models/migrations/v1_27/v372.go

@@ -0,0 +1,30 @@
+// Copyright 2026 Moko Consulting <hello@mokoconsulting.tech>
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package v1_27
+
+import (
+	"xorm.io/xorm"
+	"xorm.io/xorm/schemas"
+)
+
+// WidenActionRunJobWorkflowPayload widens action_run_job.workflow_payload on
+// MySQL/MariaDB from the default BLOB (64 KiB) to MEDIUMBLOB (16 MiB).
+//
+// ActionRunJob.WorkflowPayload was declared as an untyped []byte, so xorm created
+// a plain BLOB. At run creation the whole SingleWorkflow is interpolated (every
+// ${{ vars.* }} / git-context) and marshaled into this column; large single-job
+// workflows (e.g. deploy-*.yml with big inline SSH scripts and many vars) exceed
+// 64 KiB, so InsertRun fails with MySQL error 1406 "Data too long for column
+// 'workflow_payload'". Because workflow_dispatch returns 204 before that async
+// insert runs, the run is silently dropped ("204 but no run" — issue #815).
+//
+// Postgres (bytea) and SQLite (BLOB) have no practical size limit, so this is a
+// no-op there.
+func WidenActionRunJobWorkflowPayload(x *xorm.Engine) error {
+	if x.Dialect().URI().DBType != schemas.MYSQL {
+		return nil
+	}
+	_, err := x.Exec("ALTER TABLE `action_run_job` MODIFY COLUMN `workflow_payload` MEDIUMBLOB")
+	return err
+}