From 209b72b8179090745595048a17a51d1a14c7e026 Mon Sep 17 00:00:00 2001
From: andig <andi@evcc.io>
Date: Wed, 22 Jul 2026 11:56:07 +0200
Subject: [PATCH] Fix startup deadlock with existing metrics database (#32043)

---
 go.mod               |  2 +-
 go.sum               |  4 ++--
 server/db/db_test.go | 35 +++++++++++++++++++++++++++++++++++
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/go.mod b/go.mod
index 6b5112e70..84de61530 100644
--- a/go.mod
+++ b/go.mod
@@ -69,7 +69,7 @@ require (
 	github.com/koron/go-ssdp v0.9.1
 	github.com/korylprince/ipnetgen v1.0.1
 	github.com/libp2p/zeroconf/v2 v2.2.0
-	github.com/libtnb/sqlite v1.2.0
+	github.com/libtnb/sqlite v1.1.2
 	github.com/lorenzodonini/ocpp-go v0.19.0
 	github.com/lunixbochs/struc v0.0.0-20241101090106-8d528fa2c543
 	github.com/mabunixda/wattpilot v1.8.5
diff --git a/go.sum b/go.sum
index 17a4ea78f..6526b6c00 100644
--- a/go.sum
+++ b/go.sum
@@ -343,8 +343,8 @@ github.com/leodido/go-urn v1.4.0 h1:WT9HwE9SGECu3lg4d/dIA+jxlljEa1/ffXKmRjqdmIQ=
 github.com/leodido/go-urn v1.4.0/go.mod h1:bvxc+MVxLKB4z00jd1z+Dvzr47oO32F/QSNjSBOlFxI=
 github.com/libp2p/zeroconf/v2 v2.2.0 h1:Cup06Jv6u81HLhIj1KasuNM/RHHrJ8T7wOTS4+Tv53Q=
 github.com/libp2p/zeroconf/v2 v2.2.0/go.mod h1:fuJqLnUwZTshS3U/bMRJ3+ow/v9oid1n0DmyYyNO1Xs=
-github.com/libtnb/sqlite v1.2.0 h1:XsA7jsXHH2qmFkTWoy5YCKJybzHzWQ0flqDFP5Y9Yto=
-github.com/libtnb/sqlite v1.2.0/go.mod h1:O6vURH5fa5IgSmXd/qLAL2zSnYFUd7xSIumsmX3BrSI=
+github.com/libtnb/sqlite v1.1.2 h1:3g8nez8MwdEhn+oqt3bfKWnYJxk0ZGTO0kVA1WT+hjQ=
+github.com/libtnb/sqlite v1.1.2/go.mod h1:2PGCWOR6HqqXuoIVMmwfJ655epvRO8sw0b9kHWuKNsQ=
 github.com/lunixbochs/struc v0.0.0-20241101090106-8d528fa2c543 h1:GxMuVb9tJajC1QpbQwYNY1ZAo1EIE8I+UclBjOfjz/M=
 github.com/lunixbochs/struc v0.0.0-20241101090106-8d528fa2c543/go.mod h1:vy1vK6wD6j7xX6O6hXe621WabdtNkou2h7uRtTfRMyg=
 github.com/mabunixda/wattpilot v1.8.5 h1:pjm//7dnEiR0OHfMZ+SLlLV557Y0LMrxgjwudOsuHbQ=
diff --git a/server/db/db_test.go b/server/db/db_test.go
index 3366c961f..ef15a8e89 100644
--- a/server/db/db_test.go
+++ b/server/db/db_test.go
@@ -2,8 +2,10 @@ package db
 
 import (
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestUnitNewDriver(t *testing.T) {
@@ -63,3 +65,36 @@ func TestUnitNewDriver(t *testing.T) {
 		})
 	}
 }
+
+type migrationParent struct {
+	Id int `gorm:"column:id;primarykey"`
+}
+
+func (migrationParent) TableName() string { return "migration_parents" }
+
+type migrationChild struct {
+	ParentId int             `gorm:"column:parent_id"`
+	Parent   migrationParent `gorm:"foreignkey:ParentId;references:Id"`
+}
+
+func (migrationChild) TableName() string { return "migration_children" }
+
+// TestUnitMigrateConstraint guards against migrator implementations that pin a
+// connection and then query the pool again: the single connection deadlocks.
+func TestUnitMigrateConstraint(t *testing.T) {
+	db, err := New("sqlite", t.TempDir()+"/evcc.db")
+	require.NoError(t, err)
+
+	// existing table without the foreign key, forces the migrator to recreate it
+	require.NoError(t, db.Exec("CREATE TABLE migration_children (parent_id integer)").Error)
+
+	done := make(chan error, 1)
+	go func() { done <- db.AutoMigrate(new(migrationParent), new(migrationChild)) }()
+
+	select {
+	case err := <-done:
+		require.NoError(t, err)
+	case <-time.After(10 * time.Second):
+		t.Fatal("AutoMigrate deadlocked")
+	}
+}