perf(clickhouse): Phase 2 legacy governance — TTL cleanup, unified pool, MV, ops API

- Replace retention ALTER DELETE with MATERIALIZE TTL; use TRUNCATE for delete-all
- Remove GORM ClickHouse pool; migrate user access log reads to ChConn
- Drop query-side trim(remote_addr); enable wait_for_async_insert=1
- Add of_node_traffic_hourly MV and dashboard traffic trend fallback
- Add GET /admin/status/clickhouse operational metrics endpoint

internal/db/clickhouse.go

@@ -7,20 +7,12 @@ package db
 
 import (
 	"context"
-	"fmt"
 	"log"
-	"net/url"
-	"strconv"
-	"strings"
 	"time"
 
 	"github.com/ClickHouse/clickhouse-go/v2"
 	"github.com/ClickHouse/clickhouse-go/v2/lib/driver"
 	"github.com/Rain-kl/Wavelet/internal/config"
-	"go.opentelemetry.io/otel/attribute"
-	clickhouseDriver "gorm.io/driver/clickhouse"
-	"gorm.io/gorm"
-	"gorm.io/plugin/opentelemetry/tracing"
 )
 
 const (
@@ -31,10 +23,8 @@ const (
 )
 
 var (
-	// ChConn ClickHouse 原生连接实例，用于批量写入
+	// ChConn ClickHouse 原生连接实例，用于批量写入与查询
 	ChConn driver.Conn
-
-	chDB *gorm.DB
 )
 
 func init() {
@@ -59,36 +49,6 @@ func init() {
 		log.Fatalf("[ClickHouse] ping failed: %v\n", err)
 	}
 
-	chDB, err = gorm.Open(clickhouseDriver.New(clickhouseDriver.Config{
-		DSN: buildClickHouseDSN(),
-	}), &gorm.Config{
-		SkipDefaultTransaction: true,
-	})
-	if err != nil {
-		log.Fatalf("[ClickHouse] init gorm connection failed: %v\n", err)
-	}
-
-	if err = chDB.Use(
-		tracing.NewPlugin(
-			tracing.WithoutMetrics(),
-			tracing.WithAttributes(
-				attribute.String("db.instance", cfg.Database),
-				attribute.String("db.system", "ClickHouse"),
-			),
-		),
-	); err != nil {
-		log.Fatalf("[ClickHouse] init trace failed: %v\n", err)
-	}
-
-	sqlDB, err := chDB.DB()
-	if err != nil {
-		log.Fatalf("[ClickHouse] load sql db failed: %v\n", err)
-	}
-
-	sqlDB.SetMaxIdleConns(cfg.MaxIdleConn)
-	sqlDB.SetMaxOpenConns(cfg.MaxOpenConn)
-	sqlDB.SetConnMaxLifetime(time.Duration(cfg.ConnMaxLifetime) * time.Second)
-
 	log.Println("[ClickHouse] connection established successfully")
 }
 
@@ -105,7 +65,7 @@ func buildClickHouseOptions() *clickhouse.Options {
 		Settings: clickhouse.Settings{
 			"max_execution_time":           clickhouseMaxExecTime,
 			"async_insert":                 1,
-			"wait_for_async_insert":        0,
+			"wait_for_async_insert":        1,
 			"async_insert_max_data_size":   clickhouseAsyncInsertMaxDataSize,
 			"async_insert_busy_timeout_ms": clickhouseAsyncInsertBusyTimeoutMs,
 		},
@@ -121,44 +81,9 @@ func buildClickHouseOptions() *clickhouse.Options {
 	}
 }
 
-func buildClickHouseDSN() string {
-	cfg := config.Config.ClickHouse
-
-	chURL := &url.URL{
-		Scheme: "clickhouse",
-		Host:   strings.Join(cfg.Hosts, ","),
-		Path:   "/" + cfg.Database,
-	}
-	if cfg.Username != "" || cfg.Password != "" {
-		chURL.User = url.UserPassword(cfg.Username, cfg.Password)
-	}
-
-	query := chURL.Query()
-	query.Set("dial_timeout", fmt.Sprintf("%ds", cfg.DialTimeout))
-	query.Set("read_timeout", fmt.Sprintf("%ds", cfg.DialTimeout*clickhouseReadTimeoutFactor))
-	query.Set("max_execution_time", strconv.Itoa(clickhouseMaxExecTime))
-	// GORM uses clickhouse-go ParseDSN; unknown params are passed as server Settings.
-	query.Set("async_insert", "1")
-	query.Set("wait_for_async_insert", "0")
-	query.Set("async_insert_max_data_size", strconv.Itoa(clickhouseAsyncInsertMaxDataSize))
-	query.Set("async_insert_busy_timeout_ms", strconv.Itoa(clickhouseAsyncInsertBusyTimeoutMs))
-	query.Set("max_insert_block_size", strconv.Itoa(clickhouseAsyncInsertMaxDataSize))
-	chURL.RawQuery = query.Encode()
-
-	return chURL.String()
-}
-
-// ChDB returns a context-aware GORM ClickHouse instance.
-func ChDB(ctx context.Context) *gorm.DB {
-	if chDB == nil {
-		return nil
-	}
-	return chDB.WithContext(ctx)
-}
-
-// SetChDBForTest sets the package-level ClickHouse GORM instance for testing.
-func SetChDBForTest(d *gorm.DB) {
-	chDB = d
+// ChConnReady reports whether the native ClickHouse connection is initialized.
+func ChConnReady() bool {
+	return ChConn != nil
 }
 
 // SetChConnForTest sets the package-level native ClickHouse connection for testing.

internal/db/migrator/goose/clickhouse/202607020002_create_node_traffic_hourly_mv.sql

@@ -0,0 +1,28 @@
+-- +goose Up
+CREATE TABLE IF NOT EXISTS of_node_traffic_hourly
+(
+    node_id               String,
+    hour                  DateTime,
+    request_count         UInt64,
+    error_count           UInt64,
+    unique_visitor_count  UInt64
+)
+ENGINE = SummingMergeTree()
+PARTITION BY toYYYYMM(hour)
+ORDER BY (node_id, hour);
+
+CREATE MATERIALIZED VIEW IF NOT EXISTS of_node_traffic_hourly_mv
+TO of_node_traffic_hourly
+AS
+SELECT
+    node_id,
+    toStartOfHour(window_ended_at) AS hour,
+    sum(request_count) AS request_count,
+    sum(error_count) AS error_count,
+    sum(unique_visitor_count) AS unique_visitor_count
+FROM of_node_request_reports
+GROUP BY node_id, hour;
+
+-- +goose Down
+DROP VIEW IF EXISTS of_node_traffic_hourly_mv;
+DROP TABLE IF EXISTS of_node_traffic_hourly;