Save progress on backend app

application/camera-backend/main.py

@@ -0,0 +1,89 @@
+import io
+
+from fastapi import FastAPI, Response
+import uvicorn
+from picamera2 import Picamera2, Preview
+from threading import Condition
+import logging
+
+from picamera2.encoders import MJPEGEncoder, Quality
+from picamera2.outputs import FileOutput
+from starlette.background import BackgroundTask
+from starlette.responses import StreamingResponse
+
+app = FastAPI()
+
+@app.get("/image")
+def get_image():
+    """
+    Obtain a still image from the camera
+    :return:
+    """
+    picam2 = Picamera2()
+    capture_config = picam2.create_still_configuration(main={"size": (1920,1080)})
+    picam2.configure(capture_config)
+
+    data = io.BytesIO()
+    picam2.start()
+    picam2.capture_image(data, format="jpeg")
+
+    picam2.stop()
+    picam2.close()
+
+    return Response(content=data.getvalue(), media_type="image/jpeg")
+
+class StreamingOutput(io.BufferedIOBase):
+    def __init(self):
+        self.frame = None
+        self.condition = Condition()
+
+    def write(self, buffer):
+        with self.condition:
+            self.frame = buffer
+            self.condition.notify_all()
+
+    def read(self):
+        with self.condition:
+            self.condition.wait()
+            return self.frame
+
+def generate_frames(output):
+    while True:
+        try:
+            frame = output.read()
+            yield (b"--frame\r\n" b"Content-Type: image/jpeg\r\n\r\n" + frame + b"\r\n")
+        except Exception as e:
+            logging.error(f"Error in generate_frames: {str(e)}")
+            break
+    print("done")
+
+@app.get("/mjpeg")
+async def mjpeg():
+    picam2 = Picamera2()
+    capture_config = picam2.create_still_configuration(main={"size": (1920,1080)})
+    picam2.configure(capture_config)
+
+    output = StreamingOutput()
+    picam2.start_recording(MJPEGEncoder(), FileOutput(output), Quality.VERY_HIGH)
+    def stop():
+        logging.info("Stopping recording")
+        picam2.stop_recording()
+        picam2.close()
+
+    return StreamingResponse(
+        generate_frames(output),
+        media_type="multipare/x-mixed-replace; boundry=frame",
+        background=BackgroundTask(stop)
+    )
+
+
+def main():
+    uvicorn.run(
+        "main:app",
+        host="0.0.0.0",
+        port=8080
+    )
+
+
+if __name__ == "__main__":
+    main()