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#!/usr/bin/env python3
"""Download test fonts used by the FreeType regression test programs. These
will be copied to $FREETYPE/tests/data/ by default."""
import argparse
import collections
import hashlib
import io
import os
import requests
import sys
import zipfile
from typing import Callable, List, Optional, Tuple
# The list of download items describing the font files to install. Each
# download item is a dictionary with one of the following schemas:
#
# - File item:
#
# file_url
# Type: URL string.
# Required: Yes.
# Description: URL to download the file from.
#
# install_name
# Type: file name string
# Required: No
# Description: Installation name for the font file, only provided if
# it must be different from the original URL's basename.
#
# hex_digest
# Type: hexadecimal string
# Required: No
# Description: Digest of the input font file.
#
# - Zip items:
#
# These items correspond to one or more font files that are embedded in a
# remote zip archive. Each entry has the following fields:
#
# zip_url
# Type: URL string.
# Required: Yes.
# Description: URL to download the zip archive from.
#
# zip_files
# Type: List of file entries (see below)
# Required: Yes
# Description: A list of entries describing a single font file to be
# extracted from the archive
#
# Apart from that, some schemas are used for dictionaries used inside
# download items:
#
# - File entries:
#
# These are dictionaries describing a single font file to extract from an
# archive.
#
# filename
# Type: file path string
# Required: Yes
# Description: Path of source file, relative to the archive's
# top-level directory.
#
# install_name
# Type: file name string
# Required: No
# Description: Installation name for the font file; only provided if
# it must be different from the original filename value.
#
# hex_digest
# Type: hexadecimal string
# Required: No
# Description: Digest of the input source file
#
_DOWNLOAD_ITEMS = [
{
"zip_files": [
{
"filename": "As I Lay Dying.ttf",
"install_name": "As.I.Lay.Dying.ttf",
"hex_digest": "ef146bbc2673b387",
},
],
},
]
def digest_data(data: bytes):
"""Compute the digest of a given input byte string, which are the first
8 bytes of its sha256 hash."""
m = hashlib.sha256()
m.update(data)
return m.digest()[:8]
def check_existing(path: str, hex_digest: str):
"""Return True if |path| exists and matches |hex_digest|."""
if not os.path.exists(path) or hex_digest is None:
return False
with open(path, "rb") as f:
existing_content = f.read()
return bytes.fromhex(hex_digest) == digest_data(existing_content)
def install_file(content: bytes, dest_path: str):
"""Write a byte string to a given destination file.
Args:
content: Input data, as a byte string
dest_path: Installation path
"""
parent_path = os.path.dirname(dest_path)
if not os.path.exists(parent_path):
os.makedirs(parent_path)
with open(dest_path, "wb") as f:
f.write(content)
def download_file(url: str, expected_digest: Optional[bytes] = None):
"""Download a file from a given URL.
Args:
url: Input URL
expected_digest: Optional digest of the file
as a byte string
Returns:
URL content as binary string.
"""
r = requests.get(url, allow_redirects=True)
content = r.content
if expected_digest is not None:
digest = digest_data(r.content)
if digest != expected_digest:
raise ValueError(
"%s has invalid digest %s (expected %s)"
% (url, digest.hex(), expected_digest.hex())
)
return content
def extract_file_from_zip_archive(
archive: zipfile.ZipFile,
archive_name: str,
filepath: str,
expected_digest: Optional[bytes] = None,
):
"""Extract a file from a given zipfile.ZipFile archive.
Args:
archive: Input ZipFile objec.
archive_name: Archive name or URL, only used to generate a
human-readable error message.
filepath: Input filepath in archive.
expected_digest: Optional digest for the file.
Returns:
A new File instance corresponding to the extract file.
Raises:
ValueError if expected_digest is not None and does not match the
extracted file.
"""
file = archive.open(filepath)
if expected_digest is not None:
digest = digest_data(archive.open(filepath).read())
if digest != expected_digest:
raise ValueError(
"%s in zip archive at %s has invalid digest %s (expected %s)"
% (filepath, archive_name, digest.hex(), expected_digest.hex())
)
return file.read()
def _get_and_install_file(
install_path: str,
hex_digest: Optional[str],
force_download: bool,
get_content: Callable[[], bytes],
) -> bool:
if not force_download and hex_digest is not None \
and os.path.exists(install_path):
with open(install_path, "rb") as f:
content: bytes = f.read()
if bytes.fromhex(hex_digest) == digest_data(content):
return False
content = get_content()
install_file(content, install_path)
return True
def download_and_install_item(
item: dict, install_dir: str, force_download: bool
) -> List[Tuple[str, bool]]:
"""Download and install one item.
Args:
item: Download item as a dictionary, see above for schema.
install_dir: Installation directory.
force_download: Set to True to force download and installation, even
if the font file is already installed with the right content.
Returns:
A list of (install_name, status) tuples, where 'install_name' is the
file's installation name under 'install_dir', and 'status' is a
boolean that is True to indicate that the file was downloaded and
installed, or False to indicate that the file is already installed
with the right content.
"""
if "file_url" in item:
file_url = item["file_url"]
install_name = item.get("install_name", os.path.basename(file_url))
install_path = os.path.join(install_dir, install_name)
hex_digest = item.get("hex_digest")
def get_content():
return download_file(file_url, hex_digest)
status = _get_and_install_file(
install_path, hex_digest, force_download, get_content
)
return [(install_name, status)]
if "zip_url" in item:
# One or more files from a zip archive.
archive_url = item["zip_url"]
archive = zipfile.ZipFile(io.BytesIO(download_file(archive_url)))
result = []
for f in item["zip_files"]:
filename = f["filename"]
install_name = f.get("install_name", filename)
hex_digest = f.get("hex_digest")
def get_content():
return extract_file_from_zip_archive(
archive,
archive_url,
filename,
bytes.fromhex(hex_digest) if hex_digest else None,
)
status = _get_and_install_file(
os.path.join(install_dir, install_name),
hex_digest,
force_download,
get_content,
)
result.append((install_name, status))
return result
else:
raise ValueError("Unknown download item schema: %s" % item)
def main():
parser = argparse.ArgumentParser(description=__doc__)
# Assume this script is under tests/scripts/ and tests/data/
# is the default installation directory.
install_dir = os.path.normpath(
os.path.join(os.path.dirname(__file__), "..", "data")
)
parser.add_argument(
"--force",
action="store_true",
default=False,
help="Force download and installation of font files",
)
parser.add_argument(
"--install-dir",
default=install_dir,
help="Specify installation directory [%s]" % install_dir,
)
args = parser.parse_args()
for item in _DOWNLOAD_ITEMS:
for install_name, status in download_and_install_item(
item, args.install_dir, args.force
):
print("%s %s" % (install_name,
"INSTALLED" if status else "UP-TO-DATE"))
return 0
if __name__ == "__main__":
sys.exit(main())
# EOF