Claude: Add HTTP proxy seams and unit tests.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

internal/proxy/http.go

@@ -7,7 +7,7 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
+
 	"net/http"
 	"os"
 	"strconv"
@@ -31,32 +31,95 @@ type HTTPStreamProxyServer interface {
 	Close() error
 }
 
+// httpServer is the minimal contract of an HTTP server that httpStreamProxyServer drives.
+// *http.Server satisfies it. Tests may supply a fake that does not bind a real port.
+type httpServer interface {
+	ListenAndServe() error
+	Shutdown(ctx context.Context) error
+}
+
+// buildBackendHTTPURL composes the backend HTTP URL for a request path, targeting
+// the given backend IP and port. Callers append query strings separately when needed.
+func buildBackendHTTPURL(ip string, port int, path string) string {
+	return fmt.Sprintf("http://%v:%v%s", ip, port, path)
+}
+
 type httpStreamProxyServer struct {
 	// The environment interface.
 	environment env.ProxyEnvironment
 	// The load balancer for origin servers.
 	loadBalancer lb.OriginLoadBalancer
 	// The underlayer HTTP server.
-	server *http.Server
+	server httpServer
 	// The gracefully quit timeout, wait server to quit.
 	gracefulQuitTimeout time.Duration
 	// The wait group for all goroutines.
 	wg stdSync.WaitGroup
+	// shutdown gracefully shuts down the underlying HTTP server. Defaults to
+	// v.server.Shutdown; tests may override via a functional option to verify
+	// the shutdown contract without binding a real socket.
+	shutdown func(ctx context.Context) error
+	// newServer constructs the underlying HTTP server bound to addr and the
+	// ServeMux that handlers are registered on. Defaults to a real http.Server
+	// and ServeMux; tests may override via a functional option to supply a fake
+	// server that does not bind a real port.
+	newServer func(addr string) (httpServer, *http.ServeMux)
+	// newHLSStream constructs a per-stream HLS playback object for the given
+	// stream URL pair. Defaults to newHLSPlayStream pre-wired with this server's
+	// load balancer and a fresh SPBHID; tests may override via a functional option.
+	newHLSStream func(streamURL, fullURL string) *hlsPlayStream
+	// newFlvTsConn constructs a per-request HTTP-FLV/TS connection bound to ctx.
+	// Defaults to newHTTPFlvTsConnection pre-wired with this server's load
+	// balancer; tests may override via a functional option.
+	newFlvTsConn func(ctx context.Context) *httpFlvTsConnection
 }
 
-func NewHTTPStreamProxyServer(environment env.ProxyEnvironment, loadBalancer lb.OriginLoadBalancer, gracefulQuitTimeout time.Duration) HTTPStreamProxyServer {
+func NewHTTPStreamProxyServer(environment env.ProxyEnvironment, loadBalancer lb.OriginLoadBalancer, gracefulQuitTimeout time.Duration, opts ...func(*httpStreamProxyServer)) HTTPStreamProxyServer {
 	v := &httpStreamProxyServer{
 		environment:         environment,
 		loadBalancer:        loadBalancer,
 		gracefulQuitTimeout: gracefulQuitTimeout,
 	}
+
+	// Default shutdown: delegate to the underlying http.Server. The closure
+	// captures v rather than v.server so the dereference happens at call time,
+	// after Run() has assigned v.server.
+	v.shutdown = func(ctx context.Context) error {
+		return v.server.Shutdown(ctx)
+	}
+	// Default newServer: a real http.Server and ServeMux pair.
+	v.newServer = func(addr string) (httpServer, *http.ServeMux) {
+		mux := http.NewServeMux()
+		return &http.Server{Addr: addr, Handler: mux}, mux
+	}
+	// Default newHLSStream: a real hlsPlayStream wired with the server's load
+	// balancer and a fresh SPBHID for this stream.
+	v.newHLSStream = func(streamURL, fullURL string) *hlsPlayStream {
+		return newHLSPlayStream(func(s *hlsPlayStream) {
+			s.loadBalancer = v.loadBalancer
+			s.SRSProxyBackendHLSID = logger.GenerateContextID()
+			s.StreamURL, s.FullURL = streamURL, fullURL
+		})
+	}
+	// Default newFlvTsConn: a real httpFlvTsConnection wired with the server's
+	// load balancer and the given ctx.
+	v.newFlvTsConn = func(ctx context.Context) *httpFlvTsConnection {
+		return newHTTPFlvTsConnection(func(c *httpFlvTsConnection) {
+			c.ctx = ctx
+			c.loadBalancer = v.loadBalancer
+		})
+	}
+
+	for _, opt := range opts {
+		opt(v)
+	}
 	return v
 }
 
 func (v *httpStreamProxyServer) Close() error {
 	ctx, cancel := context.WithTimeout(context.Background(), v.gracefulQuitTimeout)
 	defer cancel()
-	v.server.Shutdown(ctx)
+	v.shutdown(ctx)
 
 	v.wg.Wait()
 	return nil
@@ -70,8 +133,8 @@ func (v *httpStreamProxyServer) Run(ctx context.Context) error {
 	}
 
 	// Create server and handler.
-	mux := http.NewServeMux()
-	v.server = &http.Server{Addr: addr, Handler: mux}
+	server, mux := v.newServer(addr)
+	v.server = server
 	logger.Debug(ctx, "HTTP Stream server listen at %v", addr)
 
 	// Shutdown the server gracefully when quiting.
@@ -82,7 +145,7 @@ func (v *httpStreamProxyServer) Run(ctx context.Context) error {
 		ctx, cancel := context.WithTimeout(context.Background(), v.gracefulQuitTimeout)
 		defer cancel()
 
-		v.server.Shutdown(ctx)
+		v.shutdown(ctx)
 	}()
 
 	// The basic version handler, also can be used as health check API.
@@ -131,11 +194,11 @@ func (v *httpStreamProxyServer) Run(ctx context.Context) error {
 				return
 			}
 
-			stream, _ := v.loadBalancer.LoadOrStoreHLS(ctx, streamURL, newHLSPlayStream(func(s *hlsPlayStream) {
-				s.loadBalancer = v.loadBalancer
-				s.SRSProxyBackendHLSID = logger.GenerateContextID()
-				s.StreamURL, s.FullURL = streamURL, fullURL
-			}))
+			stream, err := v.loadBalancer.LoadOrStoreHLS(ctx, streamURL, v.newHLSStream(streamURL, fullURL))
+			if err != nil {
+				http.Error(w, fmt.Sprintf("load or store hls %v", streamURL), http.StatusBadRequest)
+				return
+			}
 
 			stream.Initialize(ctx).(*hlsPlayStream).ServeHTTP(w, r)
 			return
@@ -155,10 +218,7 @@ func (v *httpStreamProxyServer) Run(ctx context.Context) error {
 			}
 
 			// Use HTTP pseudo streaming to proxy the request.
-			newHTTPFlvTsConnection(func(c *httpFlvTsConnection) {
-				c.ctx = ctx
-				c.loadBalancer = v.loadBalancer
-			}).ServeHTTP(w, r)
+			v.newFlvTsConn(ctx).ServeHTTP(w, r)
 			return
 		}
 
@@ -203,10 +263,15 @@ type httpFlvTsConnection struct {
 	ctx context.Context
 	// The load balancer for origin servers.
 	loadBalancer lb.OriginLoadBalancer
+	// buildBackendURL composes the backend HTTP URL for a request path. Defaults
+	// to buildBackendHTTPURL; tests may override via a functional option.
+	buildBackendURL func(ip string, port int, path string) string
 }
 
 func newHTTPFlvTsConnection(opts ...func(*httpFlvTsConnection)) *httpFlvTsConnection {
-	v := &httpFlvTsConnection{}
+	v := &httpFlvTsConnection{
+		buildBackendURL: buildBackendHTTPURL,
+	}
 	for _, opt := range opts {
 		opt(v)
 	}
@@ -266,7 +331,7 @@ func (v *httpFlvTsConnection) serveByBackend(ctx context.Context, w http.Respons
 	}
 
 	// Connect to backend SRS server via HTTP client.
-	backendURL := fmt.Sprintf("http://%v:%v%s", backend.IP, httpPort, r.URL.Path)
+	backendURL := v.buildBackendURL(backend.IP, httpPort, r.URL.Path)
 	req, err := http.NewRequestWithContext(ctx, r.Method, backendURL, nil)
 	if err != nil {
 		return errors.Wrapf(err, "create request to %v", backendURL)
@@ -319,10 +384,15 @@ type hlsPlayStream struct {
 	StreamURL string `json:"stream_url"`
 	// The full request URL for HLS streaming
 	FullURL string `json:"full_url"`
+	// buildBackendURL composes the backend HTTP URL for a request path. Defaults
+	// to buildBackendHTTPURL; tests may override via a functional option.
+	buildBackendURL func(ip string, port int, path string) string `json:"-"`
 }
 
 func newHLSPlayStream(opts ...func(*hlsPlayStream)) *hlsPlayStream {
-	v := &hlsPlayStream{}
+	v := &hlsPlayStream{
+		buildBackendURL: buildBackendHTTPURL,
+	}
 	for _, opt := range opts {
 		opt(v)
 	}
@@ -375,7 +445,7 @@ func (v *hlsPlayStream) serve(ctx context.Context, w http.ResponseWriter, r *htt
 func (v *hlsPlayStream) serveByBackend(ctx context.Context, w http.ResponseWriter, r *http.Request, backend *lb.OriginServer) error {
 	// Parse HTTP port from backend.
 	if len(backend.HTTP) == 0 {
-		return errors.Errorf("no rtmp server")
+		return errors.Errorf("no http server")
 	}
 
 	var httpPort int
@@ -386,7 +456,7 @@ func (v *hlsPlayStream) serveByBackend(ctx context.Context, w http.ResponseWrite
 	}
 
 	// Connect to backend SRS server via HTTP client.
-	backendURL := fmt.Sprintf("http://%v:%v%s", backend.IP, httpPort, r.URL.Path)
+	backendURL := v.buildBackendURL(backend.IP, httpPort, r.URL.Path)
 	if r.URL.RawQuery != "" {
 		backendURL += "?" + r.URL.RawQuery
 	}
@@ -425,7 +495,7 @@ func (v *hlsPlayStream) serveByBackend(ctx context.Context, w http.ResponseWrite
 
 	// Read all content of m3u8, append the stream ID to ts URL. Note that we only append stream ID to ts
 	// URL, to identify the stream to specified backend server. The spbhid is the SRS Proxy Backend HLS ID.
-	b, err := ioutil.ReadAll(resp.Body)
+	b, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return errors.Wrapf(err, "read stream from %v", backendURL)
 	}