1 files changed, 66 insertions, 0 deletions
diff --git a/bilibili/streaming.go b/bilibili/streaming.go
new file mode 100644
index 0000000..cc915a3
--- /dev/null
+++ b/bilibili/streaming.go
@@ -0,0 +1,66 @@
+package bilibili
+
+import (
+	"bilibili-livestream-archiver/common"
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+)
+
+// CopyLiveStream read data from a livestream video stream, copy them to a writer.
+func (b Bilibili) CopyLiveStream(
+	ctx context.Context,
+	roomId common.RoomId,
+	stream StreamingUrlInfo,
+	out io.Writer,
+) (err error) {
+	url := stream.URL
+	if !strings.HasPrefix(url, "https://") &&
+		!strings.HasPrefix(url, "http://") {
+		return fmt.Errorf("invalid URL: %v", url)
+	}
+
+	r, err := b.newGet(url)
+	if err != nil {
+		b.error.Printf("Cannot create HTTP GET instance on %v: %v", url, err)
+		return err
+	}
+
+	r.Header.Set("Referer",
+		fmt.Sprintf("https://live.bilibili.com/blanc/%d?liteVersion=true", roomId))
+
+	resp, err := b.http.Do(r)
+	if err != nil {
+		b.error.Printf("Cannot make HTTP GET request on %v: %v\n", url, err)
+		return
+	}
+
+	// 404 when not streaming
+	if resp.StatusCode == http.StatusNotFound {
+		return ErrRoomIsClosed
+	}
+
+	err = validateHttpStatus(resp)
+	if err != nil {
+		return
+	}
+
+	defer func() { _ = resp.Body.Close() }()
+
+	// guard the following copy loop
+	// if the context is cancelled, stop it by closing the reader
+	guardianCtx, cancelGuardian := context.WithCancel(ctx)
+	go func() {
+		<-guardianCtx.Done()
+		_ = resp.Body.Close()
+	}()
+	defer cancelGuardian()
+
+	// blocking copy
+	n, err := io.Copy(out, resp.Body)
+
+	b.info.Printf("Bytes copied: %v", n)
+	return
+}