refactor(arch): decouple private imports, enforce contracts and comply with cordis architecture

backend/openflare/plugins/server/kernel/repository/analytics/conn.go

@@ -0,0 +1,75 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package analytics
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"time"
+
+	"Wavelet/openflare/plugins/server/kernel/runtimeconfig"
+
+	"github.com/ClickHouse/clickhouse-go/v2"
+	"github.com/ClickHouse/clickhouse-go/v2/lib/driver"
+)
+
+var (
+	chMu   sync.RWMutex
+	chConn driver.Conn
+)
+
+// SetChConnForTest sets a mock or test ClickHouse connection.
+func SetChConnForTest(conn driver.Conn) {
+	chMu.Lock()
+	defer chMu.Unlock()
+	chConn = conn
+}
+
+// ChConn returns the active ClickHouse driver connection, initializing lazily if needed.
+func ChConn(ctx context.Context) (driver.Conn, error) {
+	chMu.RLock()
+	c := chConn
+	chMu.RUnlock()
+	if c != nil {
+		return c, nil
+	}
+
+	chMu.Lock()
+	defer chMu.Unlock()
+	if chConn != nil {
+		return chConn, nil
+	}
+
+	if !runtimeconfig.ClickHouseEnabled() {
+		return nil, fmt.Errorf("clickhouse is not enabled")
+	}
+
+	cfg := runtimeconfig.Get().ClickHouse
+	opts := &clickhouse.Options{
+		Addr: cfg.Hosts,
+		Auth: clickhouse.Auth{
+			Database: cfg.Database,
+			Username: cfg.Username,
+			Password: cfg.Password,
+		},
+		Settings: clickhouse.Settings{
+			"max_execution_time": 60,
+		},
+		Compression: &clickhouse.Compression{
+			Method: clickhouse.CompressionLZ4,
+		},
+		DialTimeout:     time.Duration(cfg.DialTimeout) * time.Second,
+		MaxOpenConns:    cfg.MaxOpenConn,
+		MaxIdleConns:    cfg.MaxIdleConn,
+		ConnMaxLifetime: time.Duration(cfg.ConnMaxLifetime) * time.Second,
+		BlockBufferSize: cfg.BlockBufferSize,
+	}
+	conn, err := clickhouse.Open(opts)
+	if err != nil {
+		return nil, fmt.Errorf("open clickhouse connection: %w", err)
+	}
+	chConn = conn
+	return chConn, nil
+}