add chain hop

chain/hop.go

@@ -2,15 +2,25 @@ package chain
 
 import (
 	"context"
+	"io"
+	"sync"
+	"time"
 
 	"github.com/go-gost/core/bypass"
 	"github.com/go-gost/core/chain"
+	"github.com/go-gost/core/logger"
 	"github.com/go-gost/core/selector"
+	"github.com/go-gost/x/internal/loader"
 )
 
 type HopOptions struct {
-	bypass   bypass.Bypass
-	selector selector.Selector[*chain.Node]
+	bypass      bypass.Bypass
+	selector    selector.Selector[*chain.Node]
+	fileLoader  loader.Loader
+	httpLoader  loader.Loader
+	redisLoader loader.Loader
+	period      time.Duration
+	logger      logger.Logger
 }
 
 type HopOption func(*HopOptions)
@@ -27,9 +37,41 @@ func SelectorHopOption(s selector.Selector[*chain.Node]) HopOption {
 	}
 }
 
+func FileLoaderHopOption(fileLoader loader.Loader) HopOption {
+	return func(opts *HopOptions) {
+		opts.fileLoader = fileLoader
+	}
+}
+
+func RedisLoaderHopOption(redisLoader loader.Loader) HopOption {
+	return func(opts *HopOptions) {
+		opts.redisLoader = redisLoader
+	}
+}
+
+func HTTPLoaderHopOption(httpLoader loader.Loader) HopOption {
+	return func(opts *HopOptions) {
+		opts.httpLoader = httpLoader
+	}
+}
+
+func ReloadPeriodHopOption(period time.Duration) HopOption {
+	return func(opts *HopOptions) {
+		opts.period = period
+	}
+}
+
+func LoggerHopOption(logger logger.Logger) HopOption {
+	return func(opts *HopOptions) {
+		opts.logger = logger
+	}
+}
+
 type chainHop struct {
-	nodes   []*chain.Node
-	options HopOptions
+	nodes      []*chain.Node
+	options    HopOptions
+	cancelFunc context.CancelFunc
+	mu         sync.RWMutex
 }
 
 func NewChainHop(nodes []*chain.Node, opts ...HopOption) chain.Hop {
@@ -40,10 +82,21 @@ func NewChainHop(nodes []*chain.Node, opts ...HopOption) chain.Hop {
 		}
 	}
 
-	return &chainHop{
-		nodes:   nodes,
-		options: options,
+	ctx, cancel := context.WithCancel(context.TODO())
+
+	hop := &chainHop{
+		nodes:      nodes,
+		options:    options,
+		cancelFunc: cancel,
 	}
+	if err := hop.reload(ctx); err != nil {
+		options.logger.Warnf("reload: %v", err)
+	}
+	if hop.options.period > 0 {
+		go hop.periodReload(ctx)
+	}
+
+	return hop
 }
 
 func (p *chainHop) Nodes() []*chain.Node {
@@ -85,3 +138,61 @@ func (p *chainHop) Select(ctx context.Context, opts ...chain.SelectOption) *chai
 	}
 	return nodes[0]
 }
+
+func (p *chainHop) periodReload(ctx context.Context) error {
+	period := p.options.period
+	if period < time.Second {
+		period = time.Second
+	}
+	ticker := time.NewTicker(period)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ticker.C:
+			if err := p.reload(ctx); err != nil {
+				p.options.logger.Warnf("reload: %v", err)
+				// return err
+			}
+		case <-ctx.Done():
+			return ctx.Err()
+		}
+	}
+}
+
+func (p *chainHop) reload(ctx context.Context) error {
+	_, err := p.load(ctx)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (p *chainHop) load(ctx context.Context) (data []byte, err error) {
+	if p.options.fileLoader != nil {
+		r, er := p.options.fileLoader.Load(ctx)
+		if er != nil {
+			p.options.logger.Warnf("file loader: %v", er)
+		}
+		return io.ReadAll(r)
+	}
+
+	if p.options.redisLoader != nil {
+		r, er := p.options.redisLoader.Load(ctx)
+		if er != nil {
+			p.options.logger.Warnf("redis loader: %v", er)
+		}
+		return io.ReadAll(r)
+	}
+
+	if p.options.httpLoader != nil {
+		r, er := p.options.redisLoader.Load(ctx)
+		if er != nil {
+			p.options.logger.Warnf("http loader: %v", er)
+		}
+		return io.ReadAll(r)
+	}
+
+	return
+}