scripts -> modules

modules/http_host/http_host_lib/utils.py

@@ -0,0 +1,69 @@
+import os
+import subprocess
+import sys
+from pathlib import Path
+
+import requests
+
+
+def assert_sudo():
+    if os.geteuid() != 0:
+        sys.exit('  needs sudo')
+
+
+def assert_linux():
+    if not Path('/etc/fstab').exists():
+        sys.exit('  needs to be run on Linux')
+
+
+def assert_single_process():
+    p = subprocess.run(['pgrep', '-fl', sys.argv[0]], capture_output=True, text=True)
+    lines = [l for l in p.stdout.splitlines() if 'python' in l]
+    if len(lines) >= 2:
+        sys.exit('  detected multiple processes, terminating')
+
+
+def download_if_size_differs(url: str, local_file: Path) -> bool:
+    if not local_file.exists() or local_file.stat().st_size != get_remote_file_size(url):
+        download_file_aria2(url, local_file)
+        return True
+
+    return False
+
+
+def get_remote_file_size(url: str) -> int | None:
+    r = requests.head(url, timeout=30)
+    size = r.headers.get('Content-Length')
+    return int(size) if size else None
+
+
+def download_file_aria2(url: str, local_file: Path):
+    print(f'  downloading {url} into {local_file}')
+    local_file.unlink(missing_ok=True)
+
+    subprocess.run(
+        [
+            'aria2c',
+            '--split=8',
+            '--max-connection-per-server=8',
+            '--file-allocation=none',
+            '--min-split-size=1M',
+            '-d',
+            local_file.parent,
+            '-o',
+            local_file.name,
+            url,
+        ],
+        check=True,
+    )
+
+
+def python_venv_executable() -> Path:
+    venv_path = os.environ.get('VIRTUAL_ENV')
+
+    if venv_path:
+        return Path(venv_path) / 'bin' / 'python'
+    elif sys.prefix != sys.base_prefix:
+        return Path(sys.prefix) / 'bin' / 'python'
+    else:
+        return Path(sys.executable)