Add chat API (#2233)

api-example-chat-stream.py

@@ -0,0 +1,88 @@
+import asyncio
+import json
+import sys
+
+try:
+    import websockets
+except ImportError:
+    print("Websockets package not found. Make sure it's installed.")
+
+# For local streaming, the websockets are hosted without ssl - ws://
+HOST = 'localhost:5005'
+URI = f'ws://{HOST}/api/v1/chat-stream'
+
+# For reverse-proxied streaming, the remote will likely host with ssl - wss://
+# URI = 'wss://your-uri-here.trycloudflare.com/api/v1/stream'
+
+
+async def run(user_input, history):
+    # Note: the selected defaults change from time to time.
+    request = {
+        'user_input': user_input,
+        'history': history,
+        'mode': 'instruct',  # Valid options: 'chat', 'chat-instruct', 'instruct'
+        'character': 'Example',
+        'instruction_template': 'Vicuna-v1.1',
+
+        'regenerate': False,
+        '_continue': False,
+        'stop_at_newline': False,
+        'chat_prompt_size': 2048,
+        'chat_generation_attempts': 1,
+        'chat-instruct_command': 'Continue the chat dialogue below. Write a single reply for the character "<|character|>".\n\n<|prompt|>',
+
+        'max_new_tokens': 250,
+        'do_sample': True,
+        'temperature': 0.7,
+        'top_p': 0.1,
+        'typical_p': 1,
+        'repetition_penalty': 1.18,
+        'top_k': 40,
+        'min_length': 0,
+        'no_repeat_ngram_size': 0,
+        'num_beams': 1,
+        'penalty_alpha': 0,
+        'length_penalty': 1,
+        'early_stopping': False,
+        'seed': -1,
+        'add_bos_token': True,
+        'truncation_length': 2048,
+        'ban_eos_token': False,
+        'skip_special_tokens': True,
+        'stopping_strings': []
+    }
+
+    async with websockets.connect(URI, ping_interval=None) as websocket:
+        await websocket.send(json.dumps(request))
+
+        while True:
+            incoming_data = await websocket.recv()
+            incoming_data = json.loads(incoming_data)
+
+            match incoming_data['event']:
+                case 'text_stream':
+                    yield incoming_data['history']
+                case 'stream_end':
+                    return
+
+
+async def print_response_stream(user_input, history):
+    cur_len = 0
+    async for new_history in run(user_input, history):
+        cur_message = new_history['visible'][-1][1][cur_len:]
+        cur_len += len(cur_message)
+        print(cur_message, end='')
+        sys.stdout.flush()  # If we don't flush, we won't see tokens in realtime.
+
+
+if __name__ == '__main__':
+    user_input = "Please give me a step-by-step guide on how to plant a tree in my backyard."
+
+    # Basic example
+    history = {'internal': [], 'visible': []}
+
+    # "Continue" example. Make sure to set '_continue' to True above
+    # arr = [user_input, 'Surely, here is']
+    # history = {'internal': [arr], 'visible': [arr]}
+
+    asyncio.run(print_response_stream(user_input, history))