import io
import os
from AIS import AIS, PDF
from contextlib import suppress
from onegov.file.sign.generic import SigningService
from typing import TYPE_CHECKING
if TYPE_CHECKING:
from _typeshed import SupportsRead, SupportsWrite
[docs]
class SwisscomAIS(SigningService, service_name='swisscom_ais'):
""" Sign PDFs using Swisscom's All-In Signing Service. """
def __init__(
self,
customer: str,
key_static: str,
cert_file: str,
cert_key: str
):
if not os.path.exists(cert_file):
raise FileNotFoundError(cert_file)
if not os.path.exists(cert_key):
raise FileNotFoundError(cert_key)
[docs]
cert_file = os.path.abspath(cert_file)
[docs]
cert_key = os.path.abspath(cert_key)
[docs]
self.customer = customer
[docs]
self.client = AIS(customer, key_static, cert_file, cert_key)
[docs]
def sign(
self,
infile: 'SupportsRead[bytes]',
outfile: 'SupportsWrite[bytes]'
) -> str:
if hasattr(infile, 'seek'):
with suppress(io.UnsupportedOperation):
infile.seek(0)
# NOTE: We gain nothing from a chunked read, since we need to
# keep the entire file in memory anyways.
inout_stream = io.BytesIO(infile.read())
pdf = PDF(inout_stream=inout_stream)
self.client.sign_one_pdf(pdf)
# NOTE: Same with the chunked write, the file is already in memory
outfile.write(inout_stream.getvalue())
return f'swisscom_ais/{self.customer}/{self.client.last_request_id}'