Files
sglang/test/registered/openai_server/features/test_json_mode.py
2026-03-23 00:18:45 -07:00

140 lines
4.6 KiB
Python

import json
import unittest
import openai
from sglang.srt.utils import kill_process_tree
from sglang.test.ci.ci_register import register_amd_ci, register_cuda_ci
from sglang.test.test_utils import (
DEFAULT_SMALL_MODEL_NAME_FOR_TEST,
DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH,
DEFAULT_URL_FOR_TEST,
CustomTestCase,
is_in_amd_ci,
popen_launch_server,
)
register_cuda_ci(est_time=109, suite="stage-b-test-1-gpu-small")
register_amd_ci(est_time=180, suite="stage-b-test-1-gpu-small-amd")
class JSONModeMixin:
"""Mixin class containing JSON mode test methods"""
def test_json_mode_response(self):
"""Test that response_format json_object (also known as "json mode") produces valid JSON, even without a system prompt that mentions JSON."""
response = self.client.chat.completions.create(
model=self.model,
messages=[
# We are deliberately omitting "That produces JSON" or similar phrases from the assistant prompt so that we don't have misleading test results
{
"role": "system",
"content": "You are a helpful AI assistant that gives a short answer.",
},
{"role": "user", "content": "What is the capital of Bulgaria?"},
],
temperature=0,
max_tokens=128,
response_format={"type": "json_object"},
)
text = response.choices[0].message.content
print(f"Response ({len(text)} characters): {text}")
# Verify the response is valid JSON
try:
js_obj = json.loads(text)
except json.JSONDecodeError as e:
self.fail(f"Response is not valid JSON. Error: {e}. Response: {text}")
# Verify it's actually an object (dict)
self.assertIsInstance(js_obj, dict, f"Response is not a JSON object: {text}")
def test_json_mode_with_streaming(self):
"""Test that streaming with json_object response (also known as "json mode") format works correctly, even without a system prompt that mentions JSON."""
stream = self.client.chat.completions.create(
model=self.model,
messages=[
# We are deliberately omitting "That produces JSON" or similar phrases from the assistant prompt so that we don't have misleading test results
{
"role": "system",
"content": "You are a helpful AI assistant that gives a short answer.",
},
{"role": "user", "content": "What is the capital of Bulgaria?"},
],
temperature=0,
max_tokens=128,
response_format={"type": "json_object"},
stream=True,
)
# Collect all chunks
chunks = []
for chunk in stream:
if chunk.choices[0].delta.content is not None:
chunks.append(chunk.choices[0].delta.content)
full_response = "".join(chunks)
print(
f"Concatenated Response ({len(full_response)} characters): {full_response}"
)
# Verify the combined response is valid JSON
try:
js_obj = json.loads(full_response)
except json.JSONDecodeError as e:
self.fail(
f"Streamed response is not valid JSON. Error: {e}. Response: {full_response}"
)
self.assertIsInstance(js_obj, dict)
class ServerWithGrammarBackend(CustomTestCase):
"""Base class for tests requiring a grammar backend server"""
backend = "xgrammar"
@classmethod
def setUpClass(cls):
cls.model = DEFAULT_SMALL_MODEL_NAME_FOR_TEST
cls.base_url = DEFAULT_URL_FOR_TEST
other_args = [
"--max-running-requests",
"10",
"--grammar-backend",
cls.backend,
]
if is_in_amd_ci():
other_args.append("--constrained-json-disable-any-whitespace")
cls.process = popen_launch_server(
cls.model,
cls.base_url,
timeout=DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH,
other_args=other_args,
)
cls.client = openai.Client(api_key="EMPTY", base_url=f"{cls.base_url}/v1")
@classmethod
def tearDownClass(cls):
kill_process_tree(cls.process.pid)
class TestJSONModeXGrammar(ServerWithGrammarBackend, JSONModeMixin):
backend = "xgrammar"
class TestJSONModeOutlines(ServerWithGrammarBackend, JSONModeMixin):
backend = "outlines"
class TestJSONModeLLGuidance(ServerWithGrammarBackend, JSONModeMixin):
backend = "llguidance"
if __name__ == "__main__":
unittest.main()