fix: retry precommit mysql lock conflicts

internal/storage/mysql/db_retry_integration_test.go

@@ -0,0 +1,82 @@
+package mysql
+
+import (
+	"context"
+	"database/sql"
+	"os"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+)
+
+func TestIntegrationWithTxRetriesPreCommitDeadlock(t *testing.T) {
+	dsn := os.Getenv("ORBIT_TEST_MYSQL_DSN")
+	if dsn == "" {
+		t.Skip("requires disposable MySQL")
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+	db, err := Open(ctx, dsn, 8, 4)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+	if _, err := db.ExecContext(ctx, `CREATE TABLE orbit_test_tx_retry (
+        id INT NOT NULL COMMENT '测试锁顺序行标识',
+        value INT NOT NULL COMMENT '测试事务累加值',
+        PRIMARY KEY (id)
+    ) ENGINE=InnoDB COMMENT='测试提交前死锁重试表'`); err != nil {
+		t.Fatal(err)
+	}
+	defer db.ExecContext(context.Background(), "DROP TABLE orbit_test_tx_retry")
+	if _, err := db.ExecContext(ctx, "INSERT INTO orbit_test_tx_retry(id,value) VALUES (1,0),(2,0)"); err != nil {
+		t.Fatal(err)
+	}
+
+	var barrier sync.WaitGroup
+	barrier.Add(2)
+	var callbackCalls atomic.Int32
+	run := func(first, second int) error {
+		attempt := 0
+		return WithTx(ctx, db, func(tx *sql.Tx) error {
+			attempt++
+			callbackCalls.Add(1)
+			order := []int{first, second}
+			if attempt > 1 {
+				order = []int{1, 2}
+			}
+			for index, id := range order {
+				if _, err := tx.ExecContext(ctx, "SELECT id FROM orbit_test_tx_retry WHERE id=? FOR UPDATE", id); err != nil {
+					return err
+				}
+				if attempt == 1 && index == 0 {
+					barrier.Done()
+					barrier.Wait()
+				}
+			}
+			_, err := tx.ExecContext(ctx, "UPDATE orbit_test_tx_retry SET value=value+1 WHERE id IN (1,2)")
+			return err
+		})
+	}
+
+	results := make(chan error, 2)
+	go func() { results <- run(1, 2) }()
+	go func() { results <- run(2, 1) }()
+	for i := 0; i < 2; i++ {
+		if err := <-results; err != nil {
+			t.Fatal(err)
+		}
+	}
+	if callbackCalls.Load() < 3 {
+		t.Fatalf("deadlock did not cause a bounded pre-commit retry; callback calls=%d", callbackCalls.Load())
+	}
+	var value int
+	if err := db.QueryRowContext(ctx, "SELECT COALESCE(MIN(value),0) FROM orbit_test_tx_retry").Scan(&value); err != nil {
+		t.Fatal(err)
+	}
+	if value != 2 {
+		t.Fatalf("committed value=%d want 2", value)
+	}
+	t.Logf("pre-commit deadlock recovered with %d callback attempts and two committed transactions", callbackCalls.Load())
+}