add sign_xml class method

nfelib/__init__.py

@@ -1,6 +1,7 @@
 # Copyright (C) 2023  Raphaël Valyi - Akretion <[email protected]>
 
 import os
+from os import environ
 from pathlib import Path
 from typing import Any, Dict, List, Optional
 
@@ -96,6 +97,33 @@ def _get_schema_path(cls) -> str:
             )
         return "undef"
 
+    @classmethod
+    def sign_xml(
+        cls,
+        xml: str,
+        pkcs12_data: Optional[bytes] = None,
+        pkcs12_password: Optional[str] = None,
+        doc_id: Optional[str] = None,
+    ) -> str:
+        """Sign xml file with pkcs12_data/pkcs12_password certificate.
+
+        Sometimes you need to test with a real certificate.
+        You can use the CERT_FILE and CERT_PASSWORD environment
+        variables to do tests with a real certificate data.
+        """
+        try:
+            from erpbrasil.assinatura import certificado as cert
+            from erpbrasil.assinatura.assinatura import Assinatura
+        except ImportError:
+            raise (RuntimeError("erpbrasil.assinatura package is not installed!"))
+
+        certificate = cert.Certificado(
+            arquivo=environ.get("CERT_FILE", pkcs12_data),
+            senha=environ.get("CERT_PASSWORD", pkcs12_password),
+        )
+        xml_etree = etree.fromstring(xml.encode("utf-8"))
+        return Assinatura(certificate).assina_xml2(xml_etree, doc_id)
+
     def to_xml(self, pretty_print: bool = True, ns_map: Optional[Dict] = None) -> str:
         """Serialize binding as an xml string."""
         serializer = XmlSerializer(SerializerConfig(pretty_print=pretty_print))
@@ -113,3 +141,12 @@ def validate_xml(self, schema_path: Optional[str] = None) -> List:
         """Serialize binding as xml, validate it and return possible errors."""
         xml = self.to_xml()
         return self.schema_validation(xml, schema_path)
+
+    # this was an attempt to keep the signature inside the
+    # binding before serializing it again. But at the moment it fails
+    # because xsdata will serialize the Signature elements with their namespaces.
+    # def sign(self, pkcs12_data: bytes = None, pkcs12_password: str = None, doc_id: str=None):
+    #     xml = self.to_xml(pretty_print=False)
+    #     signed_xml = self.sign_xml(xml, pkcs12_data, pkcs12_password, element)
+    #     nfe = self.from_xml(signed_xml)
+    #     return nfe

tests/nfe/test_nfe.py

@@ -36,6 +36,37 @@ def test_patched_xsdata_for_ipi(self):
             == "typing.Union[nfelib.nfe.bindings.v4_0.leiaute_nfe_v4_00.Tipi, NoneType]"
         )
 
+    def test_sign(self):
+        path = os.path.join("nfelib", "nfe", "samples", "v4_0", "leiauteNFe")
+        filename = "42210775277525000178550030000266631762885493-procNFe.xml"
+        input_file = os.path.join(path, filename)
+        parser = XmlParser()
+        nfe = parser.from_path(Path(input_file))
+        serializer = XmlSerializer(config=SerializerConfig(pretty_print=False))
+        xml = serializer.render(
+            obj=nfe, ns_map={None: "http://www.portalfiscal.inf.br/nfe"}
+        )
+        self.assertNotIn("<X509Certificate>", xml)
+        valid = (True,)
+        cert_password = "123456"
+        issuer = "EMISSOR A TESTE"
+        country = "BR"
+        subject = "CERTIFICADO VALIDO TESTE"
+        from erpbrasil.assinatura import misc
+
+        cert_data = misc.create_fake_certificate_file(
+            valid, cert_password, issuer, country, subject
+        )
+        signed_xml = nfe.sign_xml(xml, cert_data, cert_password, nfe.NFe.infNFe.Id)
+        self.assertIn("<X509Certificate>", signed_xml)
+
+        # this was an attempt to keep the signature inside the
+        # binding before serializing it again. But at the moment it fails
+        # because xsdata will serialize the Signature elements with their namespaces.
+        # signed_nfe = nfe.sign(cert_data, cert_password, nfe.NFe.infNFe.Id)
+        # signed_xml2 = signed_nfe.to_xml(pretty_print=False)
+        # self.assertEqual(signed_xml, signed_xml2)
+
     def test_in_out_leiauteNFe(self):
         path = os.path.join("nfelib", "nfe", "samples", "v4_0", "leiauteNFe")
         for filename in os.listdir(path):