Allow the signature_index to be None

When the signature_index is not set, the name's sinature zone is generated from a random int.

pythonProject/Dockerfile

@@ -4,6 +4,9 @@ FROM python:3.10-alpine
 # Set working directory
 WORKDIR /app
 
+# add required clis
+RUN apk add --no-cache openssl
+
 # Copy requirements.txt to the Docker container
 COPY requirements.txt .
 

pythonProject/sign.py

@@ -1,4 +1,5 @@
 import io
+from random import randint
 from typing import Optional
 
 from pyhanko import stamp
@@ -49,8 +50,8 @@ class SignOrchestrator:
             reason=reason,
         )
 
-    def sign(self, reason: str, signature_index: int, input_content: Buffer, on_page: int, box_place: (int, int, int, int), signer_text: str) -> io.BytesIO:
-        field_name = 'Signature' + str(signature_index)
+    def sign(self, reason: str, signature_index: int|None, input_content: Buffer, on_page: int, box_place: (int, int, int, int), signer_text: str) -> io.BytesIO:
+        field_name = 'Signature' + str(signature_index) if signature_index is not None else 'Signature'+ str(randint(1000, 99999999999))
         signature_meta = self._make_signature_metadata(reason, field_name)
 
         pdf_signer = signers.PdfSigner(

pythonProject/sign_individual.py

@@ -13,7 +13,7 @@ orchestrator = SignOrchestrator('./assets/dummy.p12',
                                 pkcs12_password=None)
 
 with open('./assets/test.pdf', 'rb') as input:
-    signed_content = orchestrator.sign(reason="first signer", signature_index=0,
+    signed_content = orchestrator.sign(reason="first signer", signature_index=None,
                                        input_content=input.read(), box_place=(300, 600, 500, 660), on_page=0,
                                        signer_text="Mme Caroline Diallo")
 
@@ -21,7 +21,7 @@ with open('./assets/test.pdf', 'rb') as input:
         output.write(signed_content.read())
 
 with open('./assets/test_signed_0.pdf', 'rb') as input:
-    signed_content = orchestrator.sign(reason="second signer", signature_index=1,
+    signed_content = orchestrator.sign(reason="second signer", signature_index=None,
                                        input_content=input.read(), box_place=(100, 600, 300, 660), on_page=0,
                                        signer_text="M. Bah Mamadou")