Simplify our docs with complicated functions into utils (#1807)

Co-authored-by: Chayenne <zhaochenyang@ucla.edu>

python/sglang/utils.py

@@ -1,12 +1,15 @@
 """Common utilities."""
 
 import base64
+import gc
 import importlib
 import json
 import logging
 import os
 import signal
+import subprocess
 import sys
+import time
 import traceback
 import urllib.request
 from concurrent.futures import ThreadPoolExecutor
@@ -16,6 +19,7 @@ from typing import Optional, Union
 
 import numpy as np
 import requests
+import torch
 from tqdm import tqdm
 
 logger = logging.getLogger(__name__)
@@ -294,3 +298,80 @@ def download_and_cache_file(url: str, filename: Optional[str] = None):
             bar.update(len(chunk))
 
     return filename
+
+
+def execute_shell_command(command: str) -> subprocess.Popen:
+    """
+    Execute a shell command and return the process handle
+
+    Args:
+        command: Shell command as a string (can include \ line continuations)
+    Returns:
+        subprocess.Popen: Process handle
+    """
+    # Replace \ newline with space and split
+    command = command.replace("\\\n", " ").replace("\\", " ")
+    parts = command.split()
+
+    return subprocess.Popen(
+        parts,
+        text=True,
+        stdout=subprocess.DEVNULL,
+        stderr=subprocess.DEVNULL,
+    )
+
+
+def wait_for_server(base_url: str, timeout: int = None) -> None:
+    """Wait for the server to be ready by polling the /v1/models endpoint.
+
+    Args:
+        base_url: The base URL of the server
+        timeout: Maximum time to wait in seconds. None means wait forever.
+    """
+    start_time = time.time()
+    while True:
+        try:
+            response = requests.get(
+                f"{base_url}/v1/models",
+                headers={"Authorization": "Bearer None"},
+            )
+            if response.status_code == 200:
+                break
+
+            if timeout and time.time() - start_time > timeout:
+                raise TimeoutError("Server did not become ready within timeout period")
+        except requests.exceptions.RequestException:
+            time.sleep(1)
+
+
+def terminate_process(process):
+    """Safely terminate a process and clean up GPU memory.
+
+    Args:
+        process: subprocess.Popen object to terminate
+    """
+    try:
+        process.terminate()
+        try:
+            process.wait(timeout=5)
+        except subprocess.TimeoutExpired:
+            if os.name != "nt":
+                try:
+                    pgid = os.getpgid(process.pid)
+                    os.killpg(pgid, signal.SIGTERM)
+                    time.sleep(1)
+                    if process.poll() is None:
+                        os.killpg(pgid, signal.SIGKILL)
+                except ProcessLookupError:
+                    pass
+            else:
+                process.kill()
+            process.wait()
+    except Exception as e:
+        print(f"Warning: {e}")
+    finally:
+        gc.collect()
+        if torch.cuda.is_available():
+            torch.cuda.empty_cache()
+            torch.cuda.ipc_collect()
+        time.sleep(2)