fix: restore reviewable migration evidence

2026-07-10 18:26:48 +08:00
commit d1bbb5370c
42 changed files with 6419 additions and 0 deletions
@@ -0,0 +1,221 @@
+package db
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net"
+	"net/url"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/ClickHouse/clickhouse-go/v2"
+)
+
+// Pool 封装 ClickHouse 连接并维护健康状态，DB 故障时不阻塞调用方。
+type Pool struct {
+	dsn               string
+	reconnectInterval time.Duration
+	mu                sync.RWMutex
+	conn              clickhouse.Conn
+	healthy           bool
+}
+
+// NewPool 创建 Pool。即使首次连接失败也返回非 nil 实例，后台会持续重试。
+func NewPool(ctx context.Context, dsn string, reconnectInterval time.Duration) *Pool {
+	p := &Pool{dsn: dsn, reconnectInterval: reconnectInterval}
+	if err := p.connect(ctx); err != nil {
+		log.Printf("[db] initial connect failed: %v (service continues without DB)", err)
+	}
+	go p.watch(ctx)
+	return p
+}
+
+func (p *Pool) connect(ctx context.Context) error {
+	cctx, cancel := context.WithTimeout(ctx, 5*time.Second)
+	defer cancel()
+	opts, err := ClickHouseOptions(p.dsn)
+	if err != nil {
+		return err
+	}
+	conn, err := clickhouse.Open(opts)
+	if err != nil {
+		return err
+	}
+	if err := conn.Ping(cctx); err != nil {
+		_ = conn.Close()
+		return err
+	}
+	// 先 migrate，再 swap：避免新连接 migrate 失败时取代掉旧的可用连接。
+	mctx, cancel := context.WithTimeout(ctx, 10*time.Second)
+	defer cancel()
+	if err := migrate(mctx, conn); err != nil {
+		_ = conn.Close()
+		log.Printf("[db] migrate failed: %v", err)
+		return err
+	}
+	p.mu.Lock()
+	if p.conn != nil {
+		_ = p.conn.Close()
+	}
+	p.conn = conn
+	p.healthy = true
+	p.mu.Unlock()
+	log.Printf("[db] connected and migrated")
+	return nil
+}
+
+// ClickHouseOptions converts the supported CLICKHOUSE_URL subset into driver options.
+func ClickHouseOptions(raw string) (*clickhouse.Options, error) {
+	if !strings.Contains(raw, "://") {
+		if err := validateHostPort(raw); err != nil {
+			return nil, fmt.Errorf("invalid CLICKHOUSE_URL: %w", err)
+		}
+		return &clickhouse.Options{Addr: []string{raw}}, nil
+	}
+
+	u, err := url.Parse(raw)
+	if err != nil {
+		return nil, fmt.Errorf("invalid CLICKHOUSE_URL: %w", err)
+	}
+	if u.Scheme != "clickhouse" && u.Scheme != "clickhouses" {
+		return nil, fmt.Errorf("invalid CLICKHOUSE_URL: unsupported scheme %q", u.Scheme)
+	}
+	if u.Fragment != "" {
+		return nil, fmt.Errorf("invalid CLICKHOUSE_URL: fragment is not allowed")
+	}
+	if err := validateHostPort(u.Host); err != nil {
+		return nil, fmt.Errorf("invalid CLICKHOUSE_URL: %w", err)
+	}
+
+	query, err := url.ParseQuery(u.RawQuery)
+	if err != nil {
+		return nil, fmt.Errorf("invalid CLICKHOUSE_URL: query: %w", err)
+	}
+	for key, values := range query {
+		switch key {
+		case "secure", "skip_verify", "compress":
+		default:
+			return nil, fmt.Errorf("invalid CLICKHOUSE_URL: unsupported parameter %q", key)
+		}
+		if len(values) != 1 {
+			return nil, fmt.Errorf("invalid CLICKHOUSE_URL: parameter %q must occur once", key)
+		}
+	}
+
+	wantSecure := u.Scheme == "clickhouses"
+	if value, ok := query["secure"]; ok {
+		secure, err := strconv.ParseBool(value[0])
+		if err != nil {
+			return nil, fmt.Errorf("invalid CLICKHOUSE_URL: secure: %w", err)
+		}
+		if secure != wantSecure {
+			return nil, fmt.Errorf("invalid CLICKHOUSE_URL: secure conflicts with %s", u.Scheme)
+		}
+	}
+	if _, ok := query["skip_verify"]; ok && !wantSecure {
+		return nil, fmt.Errorf("invalid CLICKHOUSE_URL: skip_verify requires clickhouses")
+	}
+	if value, ok := query["skip_verify"]; ok && value[0] != "" {
+		if _, err := strconv.ParseBool(value[0]); err != nil {
+			return nil, fmt.Errorf("invalid CLICKHOUSE_URL: skip_verify: %w", err)
+		}
+	}
+	if value, ok := query["compress"]; ok {
+		switch value[0] {
+		case "true", "false", "none", "zstd", "lz4", "lz4hc", "gzip", "deflate", "br":
+		default:
+			return nil, fmt.Errorf("invalid CLICKHOUSE_URL: unsupported compression %q", value[0])
+		}
+	}
+
+	// Let the driver decode userinfo/path and interpret compression and TLS values.
+	if wantSecure {
+		query.Set("secure", "true")
+		u.RawQuery = query.Encode()
+	}
+	opts, err := clickhouse.ParseDSN(u.String())
+	if err != nil {
+		return nil, fmt.Errorf("invalid CLICKHOUSE_URL: %w", err)
+	}
+	return opts, nil
+}
+
+func validateHostPort(address string) error {
+	if address == "" {
+		return fmt.Errorf("missing host and port")
+	}
+	host, port, err := net.SplitHostPort(address)
+	if err != nil {
+		return fmt.Errorf("expected host:port: %w", err)
+	}
+	if host == "" {
+		return fmt.Errorf("missing host")
+	}
+	n, err := strconv.ParseUint(port, 10, 16)
+	if err != nil || n == 0 {
+		return fmt.Errorf("invalid port %q", port)
+	}
+	return nil
+}
+
+// watch 定期探活；不健康时尝试重连。
+func (p *Pool) watch(ctx context.Context) {
+	t := time.NewTicker(p.reconnectInterval)
+	defer t.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-t.C:
+			if p.Healthy() {
+				if conn := p.Get(); conn != nil {
+					pctx, cancel := context.WithTimeout(ctx, 3*time.Second)
+					if err := conn.Ping(pctx); err != nil {
+						log.Printf("[db] ping failed, marking unhealthy: %v", err)
+						p.MarkUnhealthy()
+					}
+					cancel()
+				}
+				continue
+			}
+			if err := p.connect(ctx); err != nil {
+				log.Printf("[db] reconnect failed: %v", err)
+			}
+		}
+	}
+}
+
+// Healthy 报告连接是否可用。
+func (p *Pool) Healthy() bool {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+	return p.healthy
+}
+
+// MarkUnhealthy 由调用方在写入失败后调用。
+func (p *Pool) MarkUnhealthy() {
+	p.mu.Lock()
+	p.healthy = false
+	p.mu.Unlock()
+}
+
+// Get 返回当前连接，可能为 nil。
+func (p *Pool) Get() clickhouse.Conn {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+	return p.conn
+}
+
+// Close 释放底层连接。
+func (p *Pool) Close() {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.conn != nil {
+		_ = p.conn.Close()
+		p.conn = nil
+	}
+	p.healthy = false
+}