初始提交：短剧库源码（含转码优化 ultrafast）

2026-09-17 19:09:08 +08:00
commit 07dc0f1059
247 changed files with 43242 additions and 0 deletions
@@ -0,0 +1,192 @@
+package app
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"net"
+	"net/http"
+	"net/url"
+	"sync"
+	"time"
+)
+
+const cdnAlternateSubnet = "8.8.8.0/24"
+
+type cdnRoute struct {
+	address string
+	expires time.Time
+}
+
+type cdnTransport struct {
+	base       *http.Transport
+	resolver   *safeDNSDialer
+	mu         sync.Mutex
+	transports map[string]*http.Transport
+	preferred  map[string]cdnRoute
+}
+
+func newCDNTransport(base *http.Transport, resolver *safeDNSDialer) *cdnTransport {
+	return &cdnTransport{base: base, resolver: resolver, transports: map[string]*http.Transport{}, preferred: map[string]cdnRoute{}}
+}
+
+func (transport *cdnTransport) RoundTrip(request *http.Request) (*http.Response, error) {
+	if request.URL.Scheme != "https" || !protectedCDNHost(request.URL.Hostname()) || (request.Method != http.MethodGet && request.Method != http.MethodHead) {
+		return transport.base.RoundTrip(request)
+	}
+	var proxyURL *url.URL
+	var err error
+	if transport.base.Proxy != nil {
+		proxyURL, err = transport.base.Proxy(request)
+		if err != nil {
+			return nil, err
+		}
+	}
+	routeKey := request.URL.Host
+	if proxyURL != nil {
+		routeKey += "|" + proxyURL.String()
+	}
+	transport.mu.Lock()
+	preferred := transport.preferred[routeKey]
+	transport.mu.Unlock()
+	tried := map[string]bool{}
+	var response *http.Response
+	if preferred.address != "" && time.Now().Before(preferred.expires) {
+		tried[preferred.address] = true
+		response, err = transport.roundTripAddress(request, proxyURL, routeKey, preferred.address)
+		if err == nil {
+			return response, nil
+		}
+	} else {
+		response, err = transport.base.RoundTrip(request)
+		if err == nil {
+			return response, nil
+		}
+	}
+	if request.Context().Err() != nil {
+		return nil, request.Context().Err()
+	}
+	lastErr := err
+	subnets := []string{cdnAlternateSubnet, ""}
+	for _, subnet := range subnets {
+		entry, lookupErr := transport.resolver.lookupEntry(request.Context(), request.URL.Hostname(), subnet)
+		if lookupErr != nil {
+			if request.Context().Err() != nil {
+				return nil, request.Context().Err()
+			}
+			continue
+		}
+		for _, address := range entry.addresses {
+			if tried[address] || len(tried) >= 4 {
+				continue
+			}
+			tried[address] = true
+			response, err = transport.roundTripAddress(request, proxyURL, routeKey, address)
+			if err == nil {
+				transport.mu.Lock()
+				transport.preferred[routeKey] = cdnRoute{address: address, expires: entry.expires}
+				transport.mu.Unlock()
+				return response, nil
+			}
+			if request.Context().Err() != nil {
+				return nil, request.Context().Err()
+			}
+			lastErr = err
+		}
+	}
+	return nil, fmt.Errorf("黄果 CDN %s 连接失败（已尝试安全 DNS 回退，未改变代理模式）: %w", request.URL.Hostname(), publicError(lastErr))
+}
+
+func (transport *cdnTransport) roundTripAddress(request *http.Request, proxyURL *url.URL, routeKey, address string) (*http.Response, error) {
+	pinned := transport.pinnedTransport(request.URL.Hostname(), proxyURL, routeKey, address)
+	upstream := request.Clone(request.Context())
+	upstream.Host = request.Host
+	if upstream.Host == "" {
+		upstream.Host = request.URL.Host
+	}
+	upstream.URL.Host = address
+	if port := request.URL.Port(); port != "" {
+		upstream.URL.Host = net.JoinHostPort(address, port)
+	}
+	response, err := pinned.RoundTrip(upstream)
+	if response != nil {
+		response.Request = request
+	}
+	return response, err
+}
+
+func (transport *cdnTransport) pinnedTransport(host string, proxyURL *url.URL, routeKey, address string) *http.Transport {
+	transport.mu.Lock()
+	defer transport.mu.Unlock()
+	key := routeKey + "|" + address
+	if existing := transport.transports[key]; existing != nil {
+		return existing
+	}
+	pinned := transport.base.Clone()
+	if pinned.TLSClientConfig == nil {
+		pinned.TLSClientConfig = &tls.Config{}
+	}
+	pinned.TLSClientConfig.ServerName = host
+	pinned.Proxy = http.ProxyURL(proxyURL)
+	if proxyURL != nil && proxyURL.Scheme == "https" {
+		plainProxy := *proxyURL
+		plainProxy.Scheme = "http"
+		if plainProxy.Port() == "" {
+			plainProxy.Host = net.JoinHostPort(proxyURL.Hostname(), "443")
+		}
+		pinned.Proxy = http.ProxyURL(&plainProxy)
+		pinned.DialContext = transport.tlsProxyDialer(proxyURL.Hostname())
+	}
+	if len(transport.transports) >= 32 {
+		for expiredKey, expiredTransport := range transport.transports {
+			expiredTransport.CloseIdleConnections()
+			delete(transport.transports, expiredKey)
+			break
+		}
+	}
+	transport.transports[key] = pinned
+	return pinned
+}
+
+func (transport *cdnTransport) tlsProxyDialer(host string) func(context.Context, string, string) (net.Conn, error) {
+	return func(ctx context.Context, network, address string) (net.Conn, error) {
+		dial := transport.base.DialContext
+		if dial == nil {
+			dialer := &net.Dialer{Timeout: 10 * time.Second}
+			dial = dialer.DialContext
+		}
+		connection, err := dial(ctx, network, address)
+		if err != nil {
+			return nil, err
+		}
+		config := &tls.Config{}
+		if transport.base.TLSClientConfig != nil {
+			config = transport.base.TLSClientConfig.Clone()
+		}
+		config.ServerName = host
+		config.NextProtos = []string{"http/1.1"}
+		secured := tls.Client(connection, config)
+		if transport.base.TLSHandshakeTimeout > 0 {
+			var cancel context.CancelFunc
+			ctx, cancel = context.WithTimeout(ctx, transport.base.TLSHandshakeTimeout)
+			defer cancel()
+		}
+		if err := secured.HandshakeContext(ctx); err != nil {
+			connection.Close()
+			return nil, err
+		}
+		return secured, nil
+	}
+}
+
+func (transport *cdnTransport) CloseIdleConnections() {
+	transport.base.CloseIdleConnections()
+	transport.resolver.client.CloseIdleConnections()
+	transport.mu.Lock()
+	defer transport.mu.Unlock()
+	for key, pinned := range transport.transports {
+		pinned.CloseIdleConnections()
+		delete(transport.transports, key)
+	}
+	transport.preferred = map[string]cdnRoute{}
+}