Decoupled page transformation interface, added default transformation support

apps/documents/conf/settings.py

@@ -5,6 +5,7 @@ import tempfile
 
 from django.conf import settings
 from django.contrib.auth.models import User
+from django.utils.translation import ugettext_lazy as _
 
 from converter.api import get_page_count
 
@@ -18,6 +19,11 @@ default_available_models = {
     'User':User
 }
 
+available_transformations = {
+    'rotate': {'label':_(u'Rotate [degrees]'), 'arguments':[{'name':'degrees'}]}
+}
+
+
 # Definition
 AVAILABLE_FUNCTIONS = getattr(settings, 'DOCUMENTS_METADATA_AVAILABLE_FUNCTIONS', default_available_functions)
 AVAILABLE_MODELS = getattr(settings, 'DOCUMENTS_METADATA_AVAILABLE_MODELS', default_available_models)
@@ -44,6 +50,10 @@ MULTIPAGE_PREVIEW_SIZE = getattr(settings, 'DOCUMENTS_MULTIPAGE_PREVIEW_SIZE', '
 THUMBNAIL_SIZE = getattr(settings, 'DOCUMENTS_THUMBNAIL_SIZE', '50x50')
 DISPLAY_SIZE = getattr(settings, 'DOCUMENTS_DISPLAY_SIZE', '1200')
 
+# Transformations
+AVAILABLE_TRANSFORMATIONS = getattr(settings, 'DOCUMENTS_AVAILABLE_TRANSFORMATIONS', available_transformations)
+DEFAULT_TRANSFORMATIONS = getattr(settings, 'DOCUMENTS_DEFAULT_TRANSFORMATIONS', [])
+
 #Groups
 GROUP_MAX_RESULTS = getattr(settings, 'DOCUMENTS_GROUP_MAX_RESULTS', 20)
 GROUP_SHOW_EMPTY = getattr(settings, 'DOCUMENTS_GROUP_SHOW_EMPTY', True)

apps/documents/models.py

@@ -14,8 +14,6 @@ from django.db.models import Q
 
 from dynamic_search.api import register
 
-from converter.conf.settings import TRANFORMATION_CHOICES
-
 from documents.conf.settings import AVAILABLE_FUNCTIONS
 from documents.conf.settings import AVAILABLE_MODELS
 from documents.conf.settings import CHECKSUM_FUNCTION
@@ -27,7 +25,7 @@ from documents.conf.settings import FILESYSTEM_FILESERVING_ENABLE
 from documents.conf.settings import FILESYSTEM_FILESERVING_PATH
 from documents.conf.settings import FILESYSTEM_SLUGIFY_PATHS
 from documents.conf.settings import FILESYSTEM_MAX_RENAME_COUNT
-
+from documents.conf.settings import AVAILABLE_TRANSFORMATIONS
 
 if FILESYSTEM_SLUGIFY_PATHS == False:
     #Do not slugify path or filenames and extensions
@@ -447,21 +445,18 @@ class MetadataGroupItem(models.Model):
         verbose_name = _(u'metadata group item')
         verbose_name_plural = _(u'metadata group items')
 
+
+available_transformations = ([(name, data['label']) for name, data in AVAILABLE_TRANSFORMATIONS.items()]) if AVAILABLE_MODELS else []
+
     
 class DocumentPageTransformation(models.Model):
     document_page = models.ForeignKey(DocumentPage, verbose_name=_(u'document page'))
     order = models.PositiveIntegerField(blank=True, null=True, verbose_name=_(u'order'))
-    transformation = models.CharField(choices=TRANFORMATION_CHOICES, max_length=128, verbose_name=_(u'transformation'))
+    transformation = models.CharField(choices=available_transformations, max_length=128, verbose_name=_(u'transformation'))
     arguments = models.TextField(blank=True, null=True, verbose_name=_(u'arguments'), help_text=_(u'Use directories to indentify arguments, example: {\'degrees\':90}'))
 
     def __unicode__(self):
-        return self.get_transformation_display()
-
-    def get_transformation(self):
-        try:
-            return self.transformation % eval(self.arguments)
-        except Exception, e:
-            raise Exception(e)
+        return '%s - %s' % (self.document_page, self.get_transformation_display())
 
     class Meta:
         ordering = ('order',)

apps/documents/views.py

@@ -10,16 +10,19 @@ from django.core.files.base import File
 from django.conf import settings
 from django.utils.http import urlencode
 from django.template.defaultfilters import slugify
+from django.core.exceptions import ObjectDoesNotExist
 
+from common.utils import pretty_size
 from permissions.api import check_permissions, Unauthorized
 from filetransfers.api import serve_file
 from converter.api import convert, in_image_cache, QUALITY_DEFAULT
-from common.utils import pretty_size
+from converter import TRANFORMATION_CHOICES
 
 from utils import from_descriptor_to_tempfile
 
 from models import Document, DocumentMetadata, DocumentType, MetadataType, \
-    DocumentPage
+    DocumentPage, DocumentPageTransformation
+    
 from forms import DocumentTypeSelectForm, DocumentCreateWizard, \
         MetadataForm, DocumentForm, DocumentForm_edit, DocumentForm_view, \
         StagingDocumentForm, DocumentTypeMetadataType, DocumentPreviewForm, \
@@ -35,6 +38,8 @@ from documents.conf.settings import PREVIEW_SIZE
 from documents.conf.settings import THUMBNAIL_SIZE
 from documents.conf.settings import GROUP_MAX_RESULTS
 from documents.conf.settings import GROUP_SHOW_EMPTY
+from documents.conf.settings import DEFAULT_TRANSFORMATIONS
+
 
 from documents import PERMISSION_DOCUMENT_CREATE, \
     PERMISSION_DOCUMENT_CREATE, PERMISSION_DOCUMENT_PROPERTIES_EDIT, \
@@ -124,6 +129,20 @@ def upload_document_with_type(request, document_type_id, multiple=True):
                 instance.update_checksum()
                 instance.update_mimetype()
                 instance.update_page_count()
+                if DEFAULT_TRANSFORMATIONS:
+                    for transformation in DEFAULT_TRANSFORMATIONS:
+                        if 'name' in transformation:
+                            for document_page in instance.documentpage_set.all():
+                                page_transformation = DocumentPageTransformation(
+                                    document_page=document_page,
+                                    order=0, 
+                                    transformation=transformation['name'])
+                                if 'arguments' in transformation:
+                                    page_transformation.arguments = transformation['arguments']
+                                
+                                page_transformation.save()
+                        
+                        
 
                 if 'document_type_available_filenames' in local_form.cleaned_data:
                     if local_form.cleaned_data['document_type_available_filenames']:
@@ -445,17 +464,20 @@ def get_document_image(request, document_id, size=PREVIEW_SIZE, quality=QUALITY_
     page = int(request.GET.get('page', 1))
     transformation_list = []
     try:
+        #Catch invalid or non existing pages
         document_page = DocumentPage.objects.get(document=document, page_number=page)
     
-        for tranformation in document_page.documentpagetransformation_set.all():
+        for page_transformation in document_page.documentpagetransformation_set.all():
             try:
-                transformation_list.append(tranformation.get_transformation())
+                if page_transformation.transformation in TRANFORMATION_CHOICES:
+                    output = TRANFORMATION_CHOICES[page_transformation.transformation] % eval(page_transformation.arguments)
+                    transformation_list.append(output)
             except Exception, e:
                 if request.user.is_staff:
-                    messages.warning(request, _(u'Transformation %s error: %s' % (tranformation, e)))
+                    messages.warning(request, _(u'Error for transformation %s:, %s' % (page_transformation.get_transformation_display(), e)))
                 else:
                     pass
-    except:
+    except ObjectDoesNotExist:
         pass
 
     tranformation_string = ' '.join(transformation_list)