Files
mayan-edms/mayan/apps/document_indexing/models.py
Roberto Rosario 5e4518211f Remove related attribute of check_access
Remove filter_by_access. Replaced by restrict_queryset.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>
2019-05-07 02:26:50 -04:00

481 lines
17 KiB
Python

from __future__ import absolute_import, unicode_literals
import logging
from django.db import models, transaction
from django.template import Context, Template
from django.urls import reverse
from django.utils.encoding import force_text, python_2_unicode_compatible
from django.utils.translation import ugettext, ugettext_lazy as _
from mptt.fields import TreeForeignKey
from mptt.models import MPTTModel
from mayan.apps.acls.models import AccessControlList
from mayan.apps.documents.events import event_document_type_edited
from mayan.apps.documents.models import Document, DocumentType
from mayan.apps.documents.permissions import permission_document_view
from mayan.apps.lock_manager.exceptions import LockError
from mayan.apps.lock_manager.runtime import locking_backend
from .events import event_index_template_created, event_index_template_edited
from .managers import (
DocumentIndexInstanceNodeManager, IndexManager, IndexInstanceNodeManager
)
logger = logging.getLogger(__name__)
@python_2_unicode_compatible
class Index(models.Model):
"""
Parent model that defines an index and hold all the relationship for its
template and instance when resolved.
"""
label = models.CharField(
max_length=128, unique=True, verbose_name=_('Label')
)
slug = models.SlugField(
help_text=_(
'This value will be used by other apps to reference this index.'
), max_length=128, unique=True, verbose_name=_('Slug')
)
enabled = models.BooleanField(
default=True,
help_text=_(
'Causes this index to be visible and updated when document data '
'changes.'
),
verbose_name=_('Enabled')
)
document_types = models.ManyToManyField(
related_name='indexes', to=DocumentType, verbose_name=_('Document types')
)
objects = IndexManager()
class Meta:
ordering = ('label',)
verbose_name = _('Index')
verbose_name_plural = _('Indexes')
def __str__(self):
return self.label
def document_types_add(self, queryset, _user=None):
with transaction.atomic():
event_index_template_edited.commit(
actor=_user, target=self
)
for obj in queryset:
self.document_types.add(obj)
event_document_type_edited.commit(
actor=_user, action_object=self, target=obj
)
def document_types_remove(self, queryset, _user=None):
with transaction.atomic():
event_index_template_edited.commit(
actor=_user, target=self
)
for obj in queryset:
self.document_types.remove(obj)
event_document_type_edited.commit(
actor=_user, action_object=self, target=obj
)
def get_absolute_url(self):
try:
return reverse(
viewname='indexing:index_instance_node_view',
kwargs={'pk': self.instance_root.pk}
)
except IndexInstanceNode.DoesNotExist:
return '#'
def get_document_types_names(self):
return ', '.join(
[
force_text(document_type) for document_type in self.document_types.all()
] or ['None']
)
def index_document(self, document):
"""
Method to start the indexing process for a document. The entire process
happens inside one transaction. The document is first removed from all
the index nodes to which it already belongs. The different index
templates that match this document's type are evaluated and for each
result a node is fetched or created and the document is added to that
node.
"""
logger.debug('Index; Indexing document: %s', document)
with transaction.atomic():
# Remove the document from all instance nodes from
# this index
for index_instance_node in IndexInstanceNode.objects.filter(index_template_node__index=self, documents=document):
index_instance_node.remove_document(document=document)
# Delete all empty nodes. Starting from the bottom up
for index_instance_node in self.instance_root.get_leafnodes():
index_instance_node.delete_empty()
self.template_root.index_document(document=document)
@property
def instance_root(self):
return self.template_root.get_instance_root_node()
def natural_key(self):
return (self.slug,)
def rebuild(self):
"""
Delete and reconstruct the index by deleting of all its instance nodes
and recreating them for the documents whose types are associated with
this index
"""
# Delete all index instance nodes by deleting the root index
# instance node. All child index instance nodes will be cascade
# deleted.
try:
self.instance_root.delete()
except IndexInstanceNode.DoesNotExist:
# Empty index, ignore this exception
pass
# Create the new root index instance node
self.template_root.index_instance_nodes.create()
# Re-index each document with a type associated with this index
for document in Document.objects.filter(document_type__in=self.document_types.all()):
# Evaluate each index template node for each document
# associated with this index.
self.index_document(document=document)
def save(self, *args, **kwargs):
_user = kwargs.pop('_user', None)
with transaction.atomic():
is_new = not self.pk
super(Index, self).save(*args, **kwargs)
if is_new:
# Automatically create the root index template node
IndexTemplateNode.objects.get_or_create(parent=None, index=self)
event_index_template_created.commit(
actor=_user, target=self
)
else:
event_index_template_edited.commit(
actor=_user, target=self
)
@property
def template_root(self):
"""
Return the root node for this index.
"""
return self.node_templates.get(parent=None)
class IndexInstance(Index):
"""
Model that represents an evaluated index. This is an index whose nodes
have been evaluated against a series of documents. If is a proxy model
at the moment.
"""
class Meta:
proxy = True
verbose_name = _('Index instance')
verbose_name_plural = _('Index instances')
def get_instance_node_count(self):
try:
return self.instance_root.get_descendant_count()
except IndexInstanceNode.DoesNotExist:
return 0
def get_item_count(self, user):
try:
return self.instance_root.get_item_count(user=user)
except IndexInstanceNode.DoesNotExist:
return 0
@python_2_unicode_compatible
class IndexTemplateNode(MPTTModel):
"""
The template to generate an index. Each entry represents a level in a
hierarchy of levels. Each level can contain further levels or a list of
documents but not both.
"""
parent = TreeForeignKey(
blank=True, null=True, on_delete=models.CASCADE, to='self',
)
index = models.ForeignKey(
on_delete=models.CASCADE, related_name='node_templates', to=Index,
verbose_name=_('Index')
)
expression = models.TextField(
help_text=_(
'Enter a template to render. '
'Use Django\'s default templating language '
'(https://docs.djangoproject.com/en/1.11/ref/templates/builtins/)'
),
verbose_name=_('Indexing expression')
)
enabled = models.BooleanField(
default=True,
help_text=_(
'Causes this node to be visible and updated when document data '
'changes.'
),
verbose_name=_('Enabled')
)
link_documents = models.BooleanField(
default=False,
help_text=_(
'Check this option to have this node act as a container for '
'documents and not as a parent for further nodes.'
),
verbose_name=_('Link documents')
)
class Meta:
verbose_name = _('Index node template')
verbose_name_plural = _('Indexes node template')
def __str__(self):
if self.is_root_node():
return ugettext('Root')
else:
return self.expression
def get_lock_string(self):
return 'indexing:indexing_template_node_{}'.format(self.pk)
def get_instance_root_node(self):
index_instance_root_node, create = self.index_instance_nodes.get_or_create(parent=None)
return index_instance_root_node
def index_document(self, document, acquire_lock=True, index_instance_node_parent=None):
# Start transaction after the lock in case the locking backend uses
# the database.
try:
if acquire_lock:
lock = locking_backend.acquire_lock(
self.get_lock_string()
)
except LockError:
raise
else:
try:
logger.debug(
'IndexTemplateNode; Indexing document: %s', document
)
if not index_instance_node_parent:
# I'm the root
with transaction.atomic():
index_instance_root_node = self.get_instance_root_node()
for child in self.get_children():
child.index_document(
document=document, acquire_lock=False,
index_instance_node_parent=index_instance_root_node
)
elif self.enabled:
with transaction.atomic():
logger.debug('IndexTemplateNode; non parent: evaluating')
logger.debug('My parent template is: %s', self.parent)
logger.debug(
'My parent instance node is: %s',
index_instance_node_parent
)
logger.debug(
'IndexTemplateNode; Evaluating template: %s', self.expression
)
try:
context = Context({'document': document})
template = Template(self.expression)
result = template.render(context=context)
except Exception as exception:
logger.debug('Evaluating error: %s', exception)
error_message = _(
'Error indexing document: %(document)s; expression: '
'%(expression)s; %(exception)s'
) % {
'document': document,
'expression': self.expression,
'exception': exception
}
logger.debug(error_message)
else:
logger.debug('Evaluation result: %s', result)
if result:
index_instance_node, created = self.index_instance_nodes.get_or_create(
parent=index_instance_node_parent,
value=result
)
if self.link_documents:
index_instance_node.documents.add(document)
for child in self.get_children():
child.index_document(
document=document, acquire_lock=False,
index_instance_node_parent=index_instance_node
)
finally:
if acquire_lock:
lock.release()
@python_2_unicode_compatible
class IndexInstanceNode(MPTTModel):
"""
This model represent one instance node from a index template node. That is
a node template that has been evaluated against a document and the result
from that evaluation is this node's stored values. Instances of this
model also point to the original node template.
"""
parent = TreeForeignKey(
blank=True, null=True, on_delete=models.CASCADE, to='self',
)
index_template_node = models.ForeignKey(
on_delete=models.CASCADE, related_name='index_instance_nodes',
to=IndexTemplateNode, verbose_name=_('Index template node')
)
value = models.CharField(
blank=True, db_index=True, max_length=128, verbose_name=_('Value')
)
documents = models.ManyToManyField(
related_name='index_instance_nodes', to=Document,
verbose_name=_('Documents')
)
objects = IndexInstanceNodeManager()
class Meta:
verbose_name = _('Index node instance')
verbose_name_plural = _('Indexes node instances')
def __str__(self):
return self.value
def delete_empty(self):
"""
Method to delete all empty node instances in a recursive manner.
"""
# Prevent another process to delete this node.
try:
lock = locking_backend.acquire_lock(
self.index_template_node.get_lock_string()
)
except LockError:
raise
else:
try:
if self.documents.count() == 0 and self.get_children().count() == 0:
if not self.is_root_node():
# I'm not a root node, I can be deleted
self.delete()
if self.parent.is_root_node():
# My parent is not a root node, it can be deleted
self.parent.delete_empty()
finally:
lock.release()
def get_absolute_url(self):
return reverse(
viewname='indexing:index_instance_node_view', kwargs={
'pk': self.pk
}
)
def get_children_count(self):
return self.get_children().count()
def get_descendants_count(self):
return self.get_descendants().count()
def get_descendants_document_count(self, user):
return AccessControlList.objects.restrict_queryset(
permission=permission_document_view,
queryset=Document.objects.filter(
index_instance_nodes__in=self.get_descendants(
include_self=True
)
), user=user
).count()
def get_full_path(self):
result = []
for node in self.get_ancestors(include_self=True):
if node.is_root_node():
result.append(force_text(self.index()))
else:
result.append(force_text(node))
return ' / '.join(result)
def get_item_count(self, user):
if self.index_template_node.link_documents:
queryset = AccessControlList.objects.restrict_queryset(
permission=permission_document_view, queryset=self.documents,
user=user
)
return queryset.count()
else:
return self.get_children().count()
def get_lock_string(self):
return 'indexing:index_instance_node_{}'.format(self.pk)
def index(self):
"""
Return's the index instance of this node instance.
"""
return IndexInstance.objects.get(pk=self.index_template_node.index.pk)
def remove_document(self, document):
"""
The argument `acquire_lock` controls whether or not this method
acquires or lock. The case for this is to acquire when called directly
or not to acquire when called as part of a larger index process
that already has a lock
"""
# Prevent another process to work on this node. We use the node's
# parent template node for the lock
try:
lock = locking_backend.acquire_lock(
self.index_template_node.get_lock_string()
)
except LockError:
raise
else:
try:
self.documents.remove(document)
finally:
lock.release()
class DocumentIndexInstanceNode(IndexInstanceNode):
"""
Proxy model of node instance. It is used to represent the node instance
in which a document is currently located. It is used to aid in column
registration. The inherited methods of this model should not be used.
"""
objects = DocumentIndexInstanceNodeManager()
class Meta:
proxy = True
verbose_name = _('Document index node instance')
verbose_name_plural = _('Document indexes node instances')