20260429_232813-fix: video frame display pipeline — default project seed, presigned URLs, Canvas/FrameTimeline real frames, upload-parse flow

backend/main.py

@@ -1,14 +1,18 @@
 """FastAPI application entrypoint."""
 
+import asyncio
 import logging
+import os
+import shutil
+import tempfile
 from contextlib import asynccontextmanager
 
 from fastapi import FastAPI, WebSocket, WebSocketDisconnect
 from fastapi.middleware.cors import CORSMiddleware
 
 from config import settings
-from database import Base, engine
-from minio_client import ensure_bucket_exists
+from database import Base, engine, SessionLocal
+from minio_client import ensure_bucket_exists, upload_file
 from redis_client import ping as redis_ping
 
 from routers import projects, templates, media, ai, export, auth
@@ -19,6 +23,76 @@ logging.basicConfig(
 )
 logger = logging.getLogger(__name__)
 
+DEFAULT_VIDEO_PATH = "/home/wkmgc/Desktop/Seg_Server/Data_MyVideo_1.mp4"
+
+
+def _seed_default_project_sync() -> None:
+    """Synchronously seed the default video project on first startup."""
+    import cv2
+    from models import Project, Frame
+    from services.frame_parser import parse_video, upload_frames_to_minio
+
+    db = SessionLocal()
+    try:
+        existing = db.query(Project).filter(Project.name == "Data_MyVideo_1").first()
+        if existing is not None:
+            return
+
+        if not os.path.exists(DEFAULT_VIDEO_PATH):
+            logger.warning("Default video not found at %s", DEFAULT_VIDEO_PATH)
+            return
+
+        project = Project(
+            name="Data_MyVideo_1",
+            description="默认演示视频",
+            status="pending",
+        )
+        db.add(project)
+        db.commit()
+        db.refresh(project)
+
+        with open(DEFAULT_VIDEO_PATH, "rb") as f:
+            data = f.read()
+        object_name = f"uploads/{project.id}/Data_MyVideo_1.mp4"
+        upload_file(object_name, data, content_type="video/mp4", length=len(data))
+
+        project.video_path = object_name
+        db.commit()
+
+        # Parse frames
+        tmp_dir = tempfile.mkdtemp(prefix=f"seg_seed_{project.id}_")
+        try:
+            local_path = os.path.join(tmp_dir, "video.mp4")
+            with open(local_path, "wb") as f:
+                f.write(data)
+            output_dir = os.path.join(tmp_dir, "frames")
+            os.makedirs(output_dir, exist_ok=True)
+            frame_files = parse_video(local_path, output_dir, fps=30, max_frames=100)
+
+            object_names = upload_frames_to_minio(frame_files, project.id)
+
+            for idx, obj_name in enumerate(object_names):
+                img = cv2.imread(frame_files[idx])
+                h, w = img.shape[:2] if img is not None else (None, None)
+                frame = Frame(
+                    project_id=project.id,
+                    frame_index=idx,
+                    image_url=obj_name,
+                    width=w,
+                    height=h,
+                )
+                db.add(frame)
+
+            project.status = "ready"
+            db.commit()
+            logger.info("Seeded default project id=%s with %d frames", project.id, len(object_names))
+        finally:
+            shutil.rmtree(tmp_dir, ignore_errors=True)
+    except Exception as exc:
+        logger.error("Failed to seed default project: %s", exc)
+    finally:
+        db.close()
+
 
 @asynccontextmanager
 async def lifespan(app: FastAPI):
@@ -45,6 +119,12 @@ async def lifespan(app: FastAPI):
     else:
         logger.warning("Redis connection failed.")
 
+    # Seed default project in background thread so it doesn't block startup
+    try:
+        asyncio.create_task(asyncio.to_thread(_seed_default_project_sync))
+    except Exception as exc:  # noqa: BLE001
+        logger.error("Failed to start default project seeding: %s", exc)
+
     yield
 
     # Shutdown