Move more signature functionality to the document signature app

apps/document_signatures/__init__.py

@@ -1,37 +1,49 @@
 from __future__ import absolute_import
 
+try:
+    from cStringIO import StringIO
+except ImportError:
+    from StringIO import StringIO   
+
 from django.utils.translation import ugettext_lazy as _
 
-from documents.models import Document
+from documents.models import Document, DocumentVersion
 from navigation.api import register_links, register_top_menu, \
     register_model_list_columns, register_multi_item_links, \
     register_sidebar_template
-from main.api import register_diagnostic, register_maintenance_links
+from django_gpg.runtime import gpg
-from permissions.api import register_permission, set_namespace_title
+from django_gpg.exceptions import GPGDecryptionError    
-#from project_setup.api import register_setup
+#from main.api import register_diagnostic, register_maintenance_links
 
-#from django_gpg.api import Key
+from .models import DocumentVersionSignature
+from .permissions import (
+    PERMISSION_DOCUMENT_VERIFY, 
+    PERMISSION_SIGNATURE_UPLOAD,
+    PERMISSION_SIGNATURE_DOWNLOAD
+    )
 
-PERMISSION_DOCUMENT_VERIFY = {'namespace': 'document_signatures', 'name': 'document_verify', 'label': _(u'Verify document signatures')}
-PERMISSION_SIGNATURE_UPLOAD = {'namespace': 'document_signatures', 'name': 'signature_upload', 'label': _(u'Upload detached signatures')}
-PERMISSION_SIGNATURE_DOWNLOAD = {'namespace': 'document_signatures', 'name': 'key_receive', 'label': _(u'Download detached signatures')}
-
-# Permission setup
-set_namespace_title('document_signatures', _(u'Document signatures'))
-register_permission(PERMISSION_DOCUMENT_VERIFY)
-register_permission(PERMISSION_SIGNATURE_UPLOAD)
-register_permission(PERMISSION_SIGNATURE_DOWNLOAD)
 
 def has_embedded_signature(context):
-    return context['object'].signature_state
+    return DocumentVersionSignature.objects.has_embedded_signature(context['object'])
     
 def doesnt_have_detached_signature(context):
-    return context['object'].has_detached_signature() == False    
+    return DocumentVersionSignature.objects.has_detached_signature(context['object']) == False
+
+def document_pre_open_hook(descriptor):
+    try:
+        result = gpg.decrypt_file(descriptor)
+        # gpg return a string, turn it into a file like object
+        return StringIO(result.data)
+    except GPGDecryptionError:
+        # At least return the original raw content
+        return descriptor
 
 document_signature_upload = {'text': _(u'upload signature'), 'view': 'document_signature_upload', 'args': 'object.pk', 'famfam': 'pencil_add', 'permissions': [PERMISSION_SIGNATURE_UPLOAD], 'conditional_disable': has_embedded_signature}
 document_signature_download = {'text': _(u'download signature'), 'view': 'document_signature_download', 'args': 'object.pk', 'famfam': 'disk', 'permissions': [PERMISSION_SIGNATURE_DOWNLOAD], 'conditional_disable': doesnt_have_detached_signature}
 document_verify = {'text': _(u'signatures'), 'view': 'document_verify', 'args': 'object.pk', 'famfam': 'text_signature', 'permissions': [PERMISSION_DOCUMENT_VERIFY]}
 
 register_links(Document, [document_verify], menu_name='form_header')
-
 register_links(['document_verify', 'document_signature_upload', 'document_signature_download'], [document_signature_upload, document_signature_download], menu_name='sidebar')
+
+
+DocumentVersion.register_pre_open_hook(1, document_pre_open_hook)

apps/document_signatures/models.py

@@ -1,8 +1,97 @@
+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):
@@ -13,45 +102,7 @@ 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):
+    objects = DocumentVersionSignatureManager()
-        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()
-
-    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')

apps/document_signatures/permissions.py

@@ -0,0 +1,15 @@
+from __future__ import absolute_import
+
+from django.utils.translation import ugettext_lazy as _
+
+from permissions.api import register_permission, set_namespace_title
+
+PERMISSION_DOCUMENT_VERIFY = {'namespace': 'document_signatures', 'name': 'document_verify', 'label': _(u'Verify document signatures')}
+PERMISSION_SIGNATURE_UPLOAD = {'namespace': 'document_signatures', 'name': 'signature_upload', 'label': _(u'Upload detached signatures')}
+PERMISSION_SIGNATURE_DOWNLOAD = {'namespace': 'document_signatures', 'name': 'key_receive', 'label': _(u'Download detached signatures')}
+
+# Permission setup
+set_namespace_title('document_signatures', _(u'Document signatures'))
+register_permission(PERMISSION_DOCUMENT_VERIFY)
+register_permission(PERMISSION_SIGNATURE_UPLOAD)
+register_permission(PERMISSION_SIGNATURE_DOWNLOAD)

apps/document_signatures/views.py

@@ -38,7 +38,7 @@ def document_verify(request, document_pk):
 
     RecentDocument.objects.add_document_for_user(request.user, document)
     
-    signature = document.verify_signature()
+    signature = DocumentVersionSignature.objects.verify_signature(document)
 
     signature_state = SIGNATURE_STATES.get(getattr(signature, 'status', None))
     
@@ -50,7 +50,7 @@ def document_verify(request, document_pk):
         },
     ]
 
-    if document.signature_state:
+    if DocumentVersionSignature.objects.has_embedded_signature(document):
         signature_type = _(u'embedded')
     else:
         signature_type = _(u'detached')
@@ -88,7 +88,7 @@ def document_signature_upload(request, document_pk):
         form = DetachedSignatureForm(request.POST, request.FILES)
         if form.is_valid():
             try:
-                document.add_detached_signature(request.FILES['file'])
+                DocumentVersionSignature.objects.add_detached_signature(document, request.FILES['file'])
                 messages.success(request, _(u'Detached signature uploaded successfully.'))
                 return HttpResponseRedirect(next)
             except Exception, msg:
@@ -112,8 +112,8 @@ def document_signature_download(request, document_pk):
     document = get_object_or_404(Document, pk=document_pk)
 
     try:
-        if document.has_detached_signature():
+        if DocumentVersionSignature.objects.has_detached_signature(document):
-            signature = document.detached_signature()
+            signature = DocumentVersionSignature.objects.detached_signature(document)
             return serve_file(
                 request,
                 signature,

apps/documents/models.py

@@ -26,8 +26,6 @@ from mimetype.api import (get_mimetype, get_icon_file_path,
     get_error_icon_file_path)
 from converter.literals import (DEFAULT_ZOOM_LEVEL, DEFAULT_ROTATION,
     DEFAULT_PAGE_NUMBER)
-from django_gpg.runtime import gpg
-from django_gpg.exceptions import GPGVerificationError, GPGDecryptionError
 
 from documents.conf.settings import CHECKSUM_FUNCTION
 from documents.conf.settings import UUID_FUNCTION