Move more signature functionality to the document signature app

apps/document_signatures/models.py

@@ -1,9 +1,98 @@
+import logging
+
 from django.db import models
 from django.utils.translation import ugettext_lazy as _
 
 from documents.models import DocumentVersion, get_filename_from_uuid
 from documents.conf.settings import STORAGE_BACKEND
+from django_gpg.runtime import gpg
+from django_gpg.exceptions import GPGVerificationError, GPGDecryptionError
 
+logger = logging.getLogger(__name__)
+
+
+class DocumentVersionSignatureManager(models.Manager):
+    #def update_signed_state(self, document):
+    #    document_signature, created = self.model.get_or_create(
+    #        document_version=document.latest_version,
+    #    )
+    #    if document.exists():
+    #        descriptor = document.open()
+    #        try:
+    #            document_signature.signature_state = gpg.verify_file(descriptor).status
+    #            # TODO: give use choice for auto public key fetch?
+    #            # OR maybe new config option
+    #        except GPGVerificationError:
+    #            document_signature.signature_state = None
+    #        finally:
+    #            document_signature.save()
+
+    def add_detached_signature(self, document, detached_signature):
+        document_signature, created = self.model.objects.get_or_create(
+            document_version=document.latest_version,
+        )
+        if not self.signature_state(document):
+            document_signature.signature_file = detached_signature
+            document_signature.save()
+        else:
+            raise Exception('document already has an embedded signature')
+    
+    def has_detached_signature(self, document):
+        document_signature, created = self.model.objects.get_or_create(
+            document_version=document.latest_version,
+        )        
+        if document_signature.signature_file:
+            return True
+        else:
+            return False
+            
+    def has_embedded_signature(self, document):
+        logger.debug('document: %s' % document)
+
+        if self.signature_state(document):
+            return True
+        else:
+            return False            
+    
+    def signature_state(self, document):
+        document_signature, created = self.model.objects.get_or_create(
+            document_version=document.latest_version,
+        )
+        logger.debug('created: %s' % created)
+        if created and document.exists():
+            descriptor = document.open(raw=True)
+            try:
+                document_signature.signature_state = gpg.verify_file(descriptor).status
+                # TODO: give use choice for auto public key fetch?
+                # OR maybe new config option
+            except GPGVerificationError:
+                document_signature.signature_state = None
+            finally:
+                document_signature.save()            
+    
+            #document_signature.signature_state = self.verify_signature(document).status
+            #document_signature.save()
+        
+        return document_signature.signature_state
+    
+    def detached_signature(self, document):
+        document_signature, created = self.model.objects.get_or_create(
+            document_version=document.latest_version,
+        )        
+        return document_signature.signature_file.storage.open(document_signature.signature_file.path)
+        
+    def verify_signature(self, document):
+        if self.has_detached_signature(document):
+            logger.debug('has detached signature')
+            args = (document.open(), self.detached_signature(document))
+        else:
+            args = (document.open(raw=True),)
+            
+        try:
+            return gpg.verify_w_retry(*args)
+        except GPGVerificationError:
+            return None
+      
 
 class DocumentVersionSignature(models.Model):
     '''
@@ -13,46 +102,8 @@ class DocumentVersionSignature(models.Model):
     signature_state = models.CharField(blank=True, null=True, max_length=16, verbose_name=_(u'signature state'), editable=False)
     signature_file = models.FileField(blank=True, null=True, upload_to=get_filename_from_uuid, storage=STORAGE_BACKEND(), verbose_name=_(u'signature file'), editable=False)
         
-    def update_signed_state(self, save=True):
-        if self.exists():
-            try:
-                self.signature_state = gpg.verify_file(self.open()).status
-                # TODO: give use choice for auto public key fetch?
-                # OR maybe new config option
-            except GPGVerificationError:
-                self.signature_state = None
-           
-            if save:
-                self.save()
+    objects = DocumentVersionSignatureManager()
 
-    def add_detached_signature(self, detached_signature):
-        if not self.signature_state:
-            self.signature_file = detached_signature
-            self.save()
-        else:
-            raise Exception('document already has an embedded signature')
-    
-    def has_detached_signature(self):
-        if self.signature_file:
-            return self.signature_file.storage.exists(self.signature_file.path)
-        else:
-            return False
-    
-    def detached_signature(self):
-        return self.signature_file.storage.open(self.signature_file.path)
-        
-    def verify_signature(self):
-        try:
-            if self.has_detached_signature():
-                logger.debug('has detached signature')
-                signature = gpg.verify_w_retry(self.open(), self.detached_signature())
-            else:
-                signature = gpg.verify_w_retry(self.open(raw=True))
-        except GPGVerificationError:
-            signature = None
-            
-        return signature
-        
     class Meta:
         verbose_name = _(u'document version signature')
         verbose_name_plural = _(u'document version signatures')