cpython/Tools/wasm/wasm_assets.py
2023-09-18 23:49:26 -06:00

247 lines
7.4 KiB
Python
Executable File

#!/usr/bin/env python
"""Create a WASM asset bundle directory structure.
The WASM asset bundles are pre-loaded by the final WASM build. The bundle
contains:
- a stripped down, pyc-only stdlib zip file, e.g. {PREFIX}/lib/python311.zip
- os.py as marker module {PREFIX}/lib/python3.11/os.py
- empty lib-dynload directory, to make sure it is copied into the bundle:
{PREFIX}/lib/python3.11/lib-dynload/.empty
"""
import argparse
import pathlib
import shutil
import sys
import sysconfig
import zipfile
from typing import Dict
# source directory
SRCDIR = pathlib.Path(__file__).parent.parent.parent.absolute()
SRCDIR_LIB = SRCDIR / "Lib"
# Library directory relative to $(prefix).
WASM_LIB = pathlib.PurePath("lib")
WASM_STDLIB_ZIP = (
WASM_LIB / f"python{sys.version_info.major}{sys.version_info.minor}.zip"
)
WASM_STDLIB = (
WASM_LIB / f"python{sys.version_info.major}.{sys.version_info.minor}"
)
WASM_DYNLOAD = WASM_STDLIB / "lib-dynload"
# Don't ship large files / packages that are not particularly useful at
# the moment.
OMIT_FILES = (
# regression tests
"test/",
# package management
"ensurepip/",
"venv/",
# other platforms
"_aix_support.py",
"_osx_support.py",
# webbrowser
"antigravity.py",
"webbrowser.py",
# Pure Python implementations of C extensions
"_pydecimal.py",
"_pyio.py",
# concurrent threading
"concurrent/futures/thread.py",
# Misc unused or large files
"pydoc_data/",
)
# Synchronous network I/O and protocols are not supported; for example,
# socket.create_connection() raises an exception:
# "BlockingIOError: [Errno 26] Operation in progress".
OMIT_NETWORKING_FILES = (
"email/",
"ftplib.py",
"http/",
"imaplib.py",
"mailbox.py",
"poplib.py",
"smtplib.py",
"socketserver.py",
# keep urllib.parse for pydoc
"urllib/error.py",
"urllib/request.py",
"urllib/response.py",
"urllib/robotparser.py",
"wsgiref/",
)
OMIT_MODULE_FILES = {
"_asyncio": ["asyncio/"],
"_curses": ["curses/"],
"_ctypes": ["ctypes/"],
"_decimal": ["decimal.py"],
"_dbm": ["dbm/ndbm.py"],
"_gdbm": ["dbm/gnu.py"],
"_json": ["json/"],
"_multiprocessing": ["concurrent/futures/process.py", "multiprocessing/"],
"pyexpat": ["xml/", "xmlrpc/"],
"readline": ["rlcompleter.py"],
"_sqlite3": ["sqlite3/"],
"_ssl": ["ssl.py"],
"_tkinter": ["idlelib/", "tkinter/", "turtle.py", "turtledemo/"],
"_zoneinfo": ["zoneinfo/"],
}
SYSCONFIG_NAMES = (
"_sysconfigdata__emscripten_wasm32-emscripten",
"_sysconfigdata__emscripten_wasm32-emscripten",
"_sysconfigdata__wasi_wasm32-wasi",
"_sysconfigdata__wasi_wasm64-wasi",
)
def get_builddir(args: argparse.Namespace) -> pathlib.Path:
"""Get builddir path from pybuilddir.txt"""
with open("pybuilddir.txt", encoding="utf-8") as f:
builddir = f.read()
return pathlib.Path(builddir)
def get_sysconfigdata(args: argparse.Namespace) -> pathlib.Path:
"""Get path to sysconfigdata relative to build root"""
assert isinstance(args.builddir, pathlib.Path)
data_name: str = sysconfig._get_sysconfigdata_name() # type: ignore[attr-defined]
if not data_name.startswith(SYSCONFIG_NAMES):
raise ValueError(
f"Invalid sysconfig data name '{data_name}'.", SYSCONFIG_NAMES
)
filename = data_name + ".py"
return args.builddir / filename
def create_stdlib_zip(
args: argparse.Namespace,
*,
optimize: int = 0,
) -> None:
def filterfunc(filename: str) -> bool:
pathname = pathlib.Path(filename).resolve()
return pathname not in args.omit_files_absolute
with zipfile.PyZipFile(
args.wasm_stdlib_zip,
mode="w",
compression=args.compression,
optimize=optimize,
) as pzf:
if args.compresslevel is not None:
pzf.compresslevel = args.compresslevel
pzf.writepy(args.sysconfig_data)
for entry in sorted(args.srcdir_lib.iterdir()):
entry = entry.resolve()
if entry.name == "__pycache__":
continue
if entry.name.endswith(".py") or entry.is_dir():
# writepy() writes .pyc files (bytecode).
pzf.writepy(entry, filterfunc=filterfunc)
def detect_extension_modules(args: argparse.Namespace) -> Dict[str, bool]:
modules = {}
# disabled by Modules/Setup.local ?
with open(args.buildroot / "Makefile") as f:
for line in f:
if line.startswith("MODDISABLED_NAMES="):
disabled = line.split("=", 1)[1].strip().split()
for modname in disabled:
modules[modname] = False
break
# disabled by configure?
with open(args.sysconfig_data) as f:
data = f.read()
loc: Dict[str, Dict[str, str]] = {}
exec(data, globals(), loc)
for key, value in loc["build_time_vars"].items():
if not key.startswith("MODULE_") or not key.endswith("_STATE"):
continue
if value not in {"yes", "disabled", "missing", "n/a"}:
raise ValueError(f"Unsupported value '{value}' for {key}")
modname = key[7:-6].lower()
if modname not in modules:
modules[modname] = value == "yes"
return modules
def path(val: str) -> pathlib.Path:
return pathlib.Path(val).absolute()
parser = argparse.ArgumentParser()
parser.add_argument(
"--buildroot",
help="absolute path to build root",
default=pathlib.Path(".").absolute(),
type=path,
)
parser.add_argument(
"--prefix",
help="install prefix",
default=pathlib.Path("/usr/local"),
type=path,
)
def main() -> None:
args = parser.parse_args()
relative_prefix = args.prefix.relative_to(pathlib.Path("/"))
args.srcdir = SRCDIR
args.srcdir_lib = SRCDIR_LIB
args.wasm_root = args.buildroot / relative_prefix
args.wasm_stdlib_zip = args.wasm_root / WASM_STDLIB_ZIP
args.wasm_stdlib = args.wasm_root / WASM_STDLIB
args.wasm_dynload = args.wasm_root / WASM_DYNLOAD
# bpo-17004: zipimport supports only zlib compression.
# Emscripten ZIP_STORED + -sLZ4=1 linker flags results in larger file.
args.compression = zipfile.ZIP_DEFLATED
args.compresslevel = 9
args.builddir = get_builddir(args)
args.sysconfig_data = get_sysconfigdata(args)
if not args.sysconfig_data.is_file():
raise ValueError(f"sysconfigdata file {args.sysconfig_data} missing.")
extmods = detect_extension_modules(args)
omit_files = list(OMIT_FILES)
if sysconfig.get_platform().startswith("emscripten"):
omit_files.extend(OMIT_NETWORKING_FILES)
for modname, modfiles in OMIT_MODULE_FILES.items():
if not extmods.get(modname):
omit_files.extend(modfiles)
args.omit_files_absolute = {
(args.srcdir_lib / name).resolve() for name in omit_files
}
# Empty, unused directory for dynamic libs, but required for site initialization.
args.wasm_dynload.mkdir(parents=True, exist_ok=True)
marker = args.wasm_dynload / ".empty"
marker.touch()
# os.py is a marker for finding the correct lib directory.
shutil.copy(args.srcdir_lib / "os.py", args.wasm_stdlib)
# The rest of stdlib that's useful in a WASM context.
create_stdlib_zip(args)
size = round(args.wasm_stdlib_zip.stat().st_size / 1024**2, 2)
parser.exit(0, f"Created {args.wasm_stdlib_zip} ({size} MiB)\n")
if __name__ == "__main__":
main()