Files
mayan-edms/apps/documents/models.py

308 lines
12 KiB
Python

import os
from datetime import datetime
import tempfile
from django.db import models
from django.utils.translation import ugettext_lazy as _
from django.db.models import Q
from django.contrib.auth.models import User
from django.contrib.contenttypes import generic
from django.contrib.comments.models import Comment
from python_magic import magic
from taggit.managers import TaggableManager
from dynamic_search.api import register
from converter.api import get_page_count
from converter import TRANFORMATION_CHOICES
from metadata.classes import MetadataObject
from documents.conf.settings import CHECKSUM_FUNCTION
from documents.conf.settings import UUID_FUNCTION
from documents.conf.settings import STORAGE_BACKEND
from documents.conf.settings import AVAILABLE_TRANSFORMATIONS
from documents.conf.settings import DEFAULT_TRANSFORMATIONS
from documents.conf.settings import RECENT_COUNT
available_transformations = ([(name, data['label']) for name, data in AVAILABLE_TRANSFORMATIONS.items()])
def get_filename_from_uuid(instance, filename):
filename, extension = os.path.splitext(filename)
instance.file_filename = filename
#remove prefix '.'
instance.file_extension = extension[1:]
uuid = UUID_FUNCTION()
instance.uuid = uuid
return uuid
class DocumentType(models.Model):
"""
Define document types or classes to which a specific set of
properties can be attached
"""
name = models.CharField(max_length=32, verbose_name=_(u'name'))
def __unicode__(self):
return self.name
class Document(models.Model):
"""
Defines a single document with it's fields and properties
"""
document_type = models.ForeignKey(DocumentType, verbose_name=_(u'document type'), null=True, blank=True)
file = models.FileField(upload_to=get_filename_from_uuid, storage=STORAGE_BACKEND(), verbose_name=_(u'file'))
uuid = models.CharField(max_length=48, default=UUID_FUNCTION(), blank=True, editable=False)
file_mimetype = models.CharField(max_length=64, default='', editable=False)
file_mime_encoding = models.CharField(max_length=64, default='', editable=False)
#FAT filename can be up to 255 using LFN
file_filename = models.CharField(max_length=255, default='', editable=False, db_index=True)
file_extension = models.CharField(max_length=16, default='', editable=False, db_index=True)
date_added = models.DateTimeField(verbose_name=_(u'added'), auto_now_add=True, db_index=True)
date_updated = models.DateTimeField(verbose_name=_(u'updated'), auto_now=True)
checksum = models.TextField(blank=True, null=True, verbose_name=_(u'checksum'), editable=False)
description = models.TextField(blank=True, null=True, verbose_name=_(u'description'), db_index=True)
tags = TaggableManager()
comments = generic.GenericRelation(
Comment,
content_type_field='content_type',
object_id_field='object_pk'
)
class Meta:
verbose_name = _(u'document')
verbose_name_plural = _(u'documents')
ordering = ['-date_added']
def __unicode__(self):
return '%s.%s' % (self.file_filename, self.file_extension)
def save(self, *args, **kwargs):
new_document = not self.pk
super(Document, self).save(*args, **kwargs)
if new_document:
#Only do this for new documents
self.update_checksum(save=False)
self.update_mimetype(save=False)
self.save()
self.update_page_count(save=False)
self.apply_default_transformations()
@models.permalink
def get_absolute_url(self):
return ('document_view_simple', [self.pk])
def get_fullname(self):
"""
Return the fullname of the document's file
"""
return os.extsep.join([self.file_filename, self.file_extension])
def update_mimetype(self, save=True):
if self.exists():
try:
source = self.open()
mime = magic.Magic(mime=True)
self.file_mimetype = mime.from_buffer(source.read())
source.seek(0)
mime_encoding = magic.Magic(mime_encoding=True)
self.file_mime_encoding = mime_encoding.from_buffer(source.read())
except:
self.file_mimetype = u''
self.file_mime_encoding = u''
finally:
if source:
source.close()
if save:
self.save()
def open(self):
"""
Return a file descriptor to a document's file irrespective of
the storage backend
"""
return self.file.storage.open(self.file.path)
def update_checksum(self, save=True):
if self.exists():
source = self.open()
self.checksum = unicode(CHECKSUM_FUNCTION(source.read()))
source.close()
if save:
self.save()
def update_page_count(self, save=True):
handle, filepath = tempfile.mkstemp()
self.save_to_file(filepath)
detected_pages = get_page_count(filepath)
os.close(handle)
try:
os.remove(filepath)
except OSError:
pass
current_pages = DocumentPage.objects.filter(document=self).order_by('page_number',)
if current_pages.count() > detected_pages:
for page in current_pages[detected_pages:]:
page.delete()
for page_number in range(detected_pages):
DocumentPage.objects.get_or_create(
document=self, page_number=page_number + 1)
if save:
self.save()
return detected_pages
def save_to_file(self, filepath, buffer_size=1024 * 1024):
input_descriptor = self.open()
output_descriptor = open(filepath, 'wb')
while True:
copy_buffer = input_descriptor.read(buffer_size)
if copy_buffer:
output_descriptor.write(copy_buffer)
else:
break
output_descriptor.close()
input_descriptor.close()
return filepath
def exists(self):
"""
Returns a boolean value that indicates if the document's file
exists in storage
"""
return self.file.storage.exists(self.file.path)
def get_metadata_string(self):
"""
Return a formated representation of a document's metadata values
"""
return u', '.join([u'%s - %s' % (metadata.metadata_type, metadata.value) for metadata in self.documentmetadata_set.select_related('metadata_type', 'document').defer('document__document_type', 'document__file', 'document__description', 'document__file_filename', 'document__uuid', 'document__date_added', 'document__date_updated', 'document__file_mimetype', 'document__file_mime_encoding')])
def apply_default_transformations(self):
#Only apply default transformations on new documents
if DEFAULT_TRANSFORMATIONS and reduce(lambda x, y: x + y, [page.documentpagetransformation_set.count() for page in self.documentpage_set.all()]) == 0:
for transformation in DEFAULT_TRANSFORMATIONS:
if 'name' in transformation:
for document_page in self.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()
class DocumentTypeFilename(models.Model):
"""
List of filenames available to a specific document type for the
quick rename functionality
"""
document_type = models.ForeignKey(DocumentType, verbose_name=_(u'document type'))
filename = models.CharField(max_length=128, verbose_name=_(u'filename'), db_index=True)
enabled = models.BooleanField(default=True, verbose_name=_(u'enabled'))
def __unicode__(self):
return self.filename
class Meta:
ordering = ['filename']
verbose_name = _(u'document type quick rename filename')
verbose_name_plural = _(u'document types quick rename filenames')
class DocumentPage(models.Model):
document = models.ForeignKey(Document, verbose_name=_(u'document'))
content = models.TextField(blank=True, null=True, verbose_name=_(u'content'), db_index=True)
page_label = models.CharField(max_length=32, blank=True, null=True, verbose_name=_(u'page label'))
page_number = models.PositiveIntegerField(default=1, editable=False, verbose_name=_(u'page number'), db_index=True)
def __unicode__(self):
return _(u'Page %(page_num)d of %(document)s') % {
'document': unicode(self.document), 'page_num': self.page_number}
class Meta:
ordering = ['page_number']
verbose_name = _(u'document page')
verbose_name_plural = _(u'document pages')
@models.permalink
def get_absolute_url(self):
return ('document_page_view', [self.pk])
def get_transformation_string(self):
transformation_list = []
warnings = []
for page_transformation in self.documentpagetransformation_set.all():
try:
if page_transformation.transformation in TRANFORMATION_CHOICES:
transformation_list.append(
TRANFORMATION_CHOICES[page_transformation.transformation] % eval(
page_transformation.arguments
)
)
except Exception, e:
warnings.append(e)
return ' '.join(transformation_list), warnings
class DocumentPageTransformation(models.Model):
document_page = models.ForeignKey(DocumentPage, verbose_name=_(u'document page'))
order = models.PositiveIntegerField(default=0, blank=True, null=True, verbose_name=_(u'order'), db_index=True)
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 dictionaries to indentify arguments, example: {\'degrees\':90}'))
def __unicode__(self):
return u'"%s" for %s' % (self.get_transformation_display(), unicode(self.document_page))
class Meta:
ordering = ('order',)
verbose_name = _(u'document page transformation')
verbose_name_plural = _(u'document page transformations')
class RecentDocumentManager(models.Manager):
def add_document_for_user(self, user, document):
RecentDocument.objects.filter(user=user, document=document).delete()
new_recent = RecentDocument(user=user, document=document, datetime_accessed=datetime.now())
new_recent.save()
to_delete = RecentDocument.objects.filter(user=user)[RECENT_COUNT:]
for recent_to_delete in to_delete:
recent_to_delete.delete()
class RecentDocument(models.Model):
"""
Keeps a list of the n most recent accessed or created document for
a given user
"""
user = models.ForeignKey(User, verbose_name=_(u'user'), editable=False)
document = models.ForeignKey(Document, verbose_name=_(u'document'), editable=False)
datetime_accessed = models.DateTimeField(verbose_name=_(u'accessed'), db_index=True)
objects = RecentDocumentManager()
def __unicode__(self):
return unicode(self.document)
class Meta:
ordering = ('-datetime_accessed',)
verbose_name = _(u'recent document')
verbose_name_plural = _(u'recent documents')
register(Document, _(u'document'), [u'document_type__name', u'file_mimetype', u'file_filename', u'file_extension', u'documentmetadata__value', u'documentpage__content', u'description', u'tags__name', u'comments__comment'])
#register(Document, _(u'document'), ['document_type__name', 'file_mimetype', 'file_extension', 'documentmetadata__value', 'documentpage__content', 'description', {'field_name':'file_filename', 'comparison':'iexact'}])