Add Python websocket client (#63)

python-api-examples/online-websocket-client-microphone.py

@@ -0,0 +1,156 @@
+#!/usr/bin/env python3
+#
+# Copyright (c)  2023  Xiaomi Corporation
+
+"""
+A websocket client for sherpa-onnx-online-websocket-server
+
+Usage:
+    ./online-websocket-client-microphone.py \
+      --server-addr localhost \
+      --server-port 6006
+
+(Note: You have to first start the server before starting the client)
+
+You can find the server at
+https://github.com/k2-fsa/sherpa-onnx/blob/master/sherpa-onnx/csrc/online-websocket-server.cc
+
+Note: The server is implemented in C++.
+
+There is also a C++ version of the client. Please see
+https://github.com/k2-fsa/sherpa-onnx/blob/master/sherpa-onnx/csrc/online-websocket-client.cc
+"""
+
+import argparse
+import asyncio
+import time
+
+import numpy as np
+
+try:
+    import sounddevice as sd
+except ImportError as e:
+    print("Please install sounddevice first. You can use")
+    print()
+    print("  pip install sounddevice")
+    print()
+    print("to install it")
+    sys.exit(-1)
+
+try:
+    import websockets
+except ImportError:
+    print("please run:")
+    print("")
+    print("  pip install websockets")
+    print("")
+    print("before you run this script")
+    print("")
+    sys.exit(-1)
+
+
+def get_args():
+    parser = argparse.ArgumentParser(
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter
+    )
+
+    parser.add_argument(
+        "--server-addr",
+        type=str,
+        default="localhost",
+        help="Address of the server",
+    )
+
+    parser.add_argument(
+        "--server-port",
+        type=int,
+        default=6006,
+        help="Port of the server",
+    )
+
+    return parser.parse_args()
+
+
+async def inputstream_generator(channels=1):
+    """Generator that yields blocks of input data as NumPy arrays.
+
+    See https://python-sounddevice.readthedocs.io/en/0.4.6/examples.html#creating-an-asyncio-generator-for-audio-blocks
+    """
+    q_in = asyncio.Queue()
+    loop = asyncio.get_event_loop()
+
+    def callback(indata, frame_count, time_info, status):
+        loop.call_soon_threadsafe(q_in.put_nowait, (indata.copy(), status))
+
+    devices = sd.query_devices()
+    print(devices)
+    default_input_device_idx = sd.default.device[0]
+    print(f'Use default device: {devices[default_input_device_idx]["name"]}')
+    print()
+    print("Started! Please speak")
+
+    stream = sd.InputStream(
+        callback=callback,
+        channels=channels,
+        dtype="float32",
+        samplerate=16000,
+        blocksize=int(0.05 * 16000),  # 0.05 seconds
+    )
+    with stream:
+        while True:
+            indata, status = await q_in.get()
+            yield indata, status
+
+
+async def receive_results(socket: websockets.WebSocketServerProtocol):
+    last_message = ""
+    async for message in socket:
+        if message != "Done!":
+            if last_message != message:
+                last_message = message
+
+                if last_message:
+                    print(last_message)
+        else:
+            return last_message
+
+
+async def run(
+    server_addr: str,
+    server_port: int,
+):
+    async with websockets.connect(
+        f"ws://{server_addr}:{server_port}"
+    ) as websocket:  # noqa
+        receive_task = asyncio.create_task(receive_results(websocket))
+        print("Started! Please Speak")
+
+        async for indata, status in inputstream_generator():
+            if status:
+                print(status)
+            indata = indata.reshape(-1)
+            indata = np.ascontiguousarray(indata)
+            await websocket.send(indata.tobytes())
+
+        decoding_results = await receive_task
+        print("\nFinal result is:\n{decoding_results}")
+
+
+async def main():
+    args = get_args()
+    print(vars(args))
+
+    server_addr = args.server_addr
+    server_port = args.server_port
+
+    await run(
+        server_addr=server_addr,
+        server_port=server_port,
+    )
+
+
+if __name__ == "__main__":
+    try:
+        asyncio.run(main())
+    except KeyboardInterrupt:
+        print("\nCaught Ctrl + C. Exiting")