API Client#
Source vllm-project/vllm.
1"""Example Python client for vllm.entrypoints.api_server"""
2
3import argparse
4import json
5from typing import Iterable, List
6
7import requests
8
9
10def clear_line(n: int = 1) -> None:
11 LINE_UP = '\033[1A'
12 LINE_CLEAR = '\x1b[2K'
13 for _ in range(n):
14 print(LINE_UP, end=LINE_CLEAR, flush=True)
15
16
17def post_http_request(prompt: str,
18 api_url: str,
19 n: int = 1,
20 stream: bool = False) -> requests.Response:
21 headers = {"User-Agent": "Test Client"}
22 pload = {
23 "prompt": prompt,
24 "n": n,
25 "use_beam_search": True,
26 "temperature": 0.0,
27 "max_tokens": 16,
28 "stream": stream,
29 }
30 response = requests.post(api_url, headers=headers, json=pload, stream=True)
31 return response
32
33
34def get_streaming_response(response: requests.Response) -> Iterable[List[str]]:
35 for chunk in response.iter_lines(chunk_size=8192,
36 decode_unicode=False,
37 delimiter=b"\0"):
38 if chunk:
39 data = json.loads(chunk.decode("utf-8"))
40 output = data["text"]
41 yield output
42
43
44def get_response(response: requests.Response) -> List[str]:
45 data = json.loads(response.content)
46 output = data["text"]
47 return output
48
49
50if __name__ == "__main__":
51 parser = argparse.ArgumentParser()
52 parser.add_argument("--host", type=str, default="localhost")
53 parser.add_argument("--port", type=int, default=8000)
54 parser.add_argument("--n", type=int, default=4)
55 parser.add_argument("--prompt", type=str, default="San Francisco is a")
56 parser.add_argument("--stream", action="store_true")
57 args = parser.parse_args()
58 prompt = args.prompt
59 api_url = f"http://{args.host}:{args.port}/generate"
60 n = args.n
61 stream = args.stream
62
63 print(f"Prompt: {prompt!r}\n", flush=True)
64 response = post_http_request(prompt, api_url, n, stream)
65
66 if stream:
67 num_printed_lines = 0
68 for h in get_streaming_response(response):
69 clear_line(num_printed_lines)
70 num_printed_lines = 0
71 for i, line in enumerate(h):
72 num_printed_lines += 1
73 print(f"Beam candidate {i}: {line!r}", flush=True)
74 else:
75 output = get_response(response)
76 for i, line in enumerate(output):
77 print(f"Beam candidate {i}: {line!r}", flush=True)