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utils.py
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utils.py
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import re
from types import ClassType
from os.path import join, abspath, split
from cStringIO import StringIO
from PIL import Image
import zope.interface
from zope.interface import implementedBy
from zope.component import getMultiAdapter
from zope.component.interfaces import ComponentLookupError
import OFS
import Globals
from Acquisition import aq_base, aq_inner, aq_parent
from DateTime import DateTime
from Products.Five import BrowserView as BaseView
from Products.Five.bridge import fromZ2Interface
from Products.CMFCore.utils import ToolInit as CMFCoreToolInit
from Products.CMFCore.utils import getToolByName
from Products.CMFPlone.UnicodeNormalizer import normalizeUnicode
from Products.CMFPlone.interfaces.Translatable import ITranslatable
import transaction
from Products.PageTemplates.GlobalTranslationService import \
getGlobalTranslationService
# Canonical way to get at CMFPlone directory
PACKAGE_HOME = Globals.package_home(globals())
WWW_DIR = join(PACKAGE_HOME, 'www')
# Log methods
from log import log
from log import log_exc
from log import log_deprecated
# Define and compile static regexes
IGNORE_REGEX = re.compile(r"[']")
FILENAME_REGEX = re.compile(r"^(.+)\.(\w{,4})$")
NON_WORD_REGEX = re.compile(r"[\W\-]+")
DANGEROUS_CHARS_REGEX = re.compile(r"[?&/:\\#]+")
EXTRA_DASHES_REGEX = re.compile(r"(^\-+)|(\-+$)")
# Settings for member image resize quality
PIL_SCALING_ALGO = Image.ANTIALIAS
PIL_QUALITY = 88
MEMBER_IMAGE_SCALE = (75, 100)
IMAGE_SCALE_PARAMS = {'scale': MEMBER_IMAGE_SCALE,
'quality': PIL_QUALITY,
'algorithm': PIL_SCALING_ALGO,
'default_format': 'PNG'}
_marker = []
class BrowserView(BaseView):
def __init__(self, context, request):
self.context = [context]
self.request = request
def parent(obj):
return aq_parent(aq_inner(obj))
def context(view):
return view.context[0]
def createBreadCrumbs(context, request):
view = getMultiAdapter((context, request), name='breadcrumbs_view')
return view.breadcrumbs()
def createTopLevelTabs(context, request, actions=None, category='portal_tabs'):
view = getMultiAdapter((context, request), name='portal_tabs_view')
return view.topLevelTabs(actions=actions, category=category)
def createNavTree(context, request, sitemap=False):
view = getMultiAdapter((context, request), name='navtree_builder_view')
return view.navigationTree()
def createSiteMap(context, request, sitemap=False):
view = getMultiAdapter((context, request), name='sitemap_builder_view')
return view.siteMap()
def _getDefaultPageView(obj, request):
"""This is a nasty hack because the view lookup fails when it occurs too
early in the publishing process because the request isn't marked with
the default skin. Explicitly marking the request appears to cause
connection errors, so we just instantiate the view manually.
"""
try:
view = getMultiAdapter((obj, request), name='default_page')
except ComponentLookupError:
# XXX: import here to avoid a circular dependency
from browser.navigation import DefaultPage
view = DefaultPage(obj, request)
return view
def isDefaultPage(obj, request, context=None):
container = parent(obj)
if container is None:
return False
view = _getDefaultPageView(container, request)
if context is None:
context = obj
return view.isDefaultPage(obj, context)
def getDefaultPage(obj, request, context=None):
# Short circuit if we are not looking at a Folder
if not obj.isPrincipiaFolderish:
return None
view = _getDefaultPageView(obj, request)
if context is None:
context = obj
return view.getDefaultPage(context)
def isIDAutoGenerated(context, id):
# In 2.1 non-autogenerated is the common case, caught exceptions are
# expensive, so let's make a cheap check first
if id.count('.') != 2:
return False
pt = getToolByName(context, 'portal_types')
portaltypes = pt.listContentTypes()
portaltypes.extend([pt.lower() for pt in portaltypes])
try:
obj_type, date_created, random_number = id.split('.')
type = ' '.join(obj_type.split('_'))
# New autogenerated ids may have a lower case portal type
if ((type in portaltypes or obj_type in portaltypes) and
DateTime(date_created) and
float(random_number)):
return True
except (ValueError, AttributeError, IndexError, DateTime.DateTimeError):
pass
return False
def lookupTranslationId(obj, page, ids):
implemented = ITranslatable.isImplementedBy(obj)
if not implemented or implemented and not obj.isTranslation():
pageobj = getattr(obj, page, None)
if (pageobj is not None and
ITranslatable.isImplementedBy(pageobj)):
translation = pageobj.getTranslation()
if (translation is not None and
ids.has_key(translation.getId())):
page = translation.getId()
return page
def pretty_title_or_id(context, obj, empty_value=_marker):
"""Return the best possible title or id of an item, regardless
of whether obj is a catalog brain or an object, but returning an
empty title marker if the id is not set (i.e. it's auto-generated).
"""
#if safe_hasattr(obj, 'aq_explicit'):
# obj = obj.aq_explicit
#title = getattr(obj, 'Title', None)
title = None
if base_hasattr(obj, 'Title'):
title = getattr(obj, 'Title', None)
if safe_callable(title):
title = title()
if title:
return title
item_id = getattr(obj, 'getId', None)
if safe_callable(item_id):
item_id = item_id()
if item_id and not isIDAutoGenerated(context, item_id):
return item_id
if empty_value is _marker:
empty_value = getEmptyTitle(context)
return empty_value
def getSiteEncoding(context):
default = 'utf-8'
pprop = getToolByName(context, 'portal_properties')
site_props = getToolByName(pprop, 'site_properties', None)
if site_props is None:
return default
return site_props.getProperty('default_charset', default)
def portal_utf8(context, str, errors='strict'):
charset = getSiteEncoding(context)
if charset.lower() in ('utf-8', 'utf8'):
# Test
unicode(str, 'utf-8', errors)
return str
else:
return unicode(str, charset, errors).encode('utf-8', errors)
def utf8_portal(context, str, errors='strict'):
charset = getSiteEncoding(context)
if charset.lower() in ('utf-8', 'utf8'):
# Test
unicode(str, 'utf-8', errors)
return str
else:
return unicode(str, 'utf-8', errors).encode(charset, errors)
def getEmptyTitle(context, translated=True):
"""Returns string to be used for objects with no title or id"""
# The default is an extra fancy unicode elipsis
empty = unicode('\x5b\xc2\xb7\xc2\xb7\xc2\xb7\x5d', 'utf-8')
if translated:
service = getGlobalTranslationService()
empty = service.translate('plone', 'title_unset', context=context, default=empty)
return empty
def typesToList(context):
ntp = getToolByName(context, 'portal_properties').navtree_properties
ttool = getToolByName(context, 'portal_types')
bl = ntp.getProperty('metaTypesNotToList', ())
bl_dict = {}
for t in bl:
bl_dict[t] = 1
all_types = ttool.listContentTypes()
wl = [t for t in all_types if not bl_dict.has_key(t)]
return wl
def normalizeString(text, context=None, encoding=None, relaxed=False):
assert (context is not None) or (encoding is not None), \
'Either context or encoding must be provided'
# Make sure we are dealing with a stringish type
if not isinstance(text, basestring):
# This most surely ends up in something the user does not expect
# to see. But at least it does not break.
text = repr(text)
# Make sure we are dealing with a unicode string
if not isinstance(text, unicode):
if encoding is None:
encoding = getSiteEncoding(context)
text = unicode(text, encoding)
text = text.strip()
if not relaxed:
text = text.lower()
text = normalizeUnicode(text)
base = text
ext = ""
m = FILENAME_REGEX.match(text)
if m is not None:
base = m.groups()[0]
ext = m.groups()[1]
base = IGNORE_REGEX.sub("", base)
if not relaxed:
base = NON_WORD_REGEX.sub("-", base)
else:
base = DANGEROUS_CHARS_REGEX.sub("-", base)
base = EXTRA_DASHES_REGEX.sub("", base)
if ext != "":
base = base + "." + ext
return base
class IndexIterator:
"""An iterator used to generate tabindexes. Note that tabindexes are not as
good for accessibility as once thought, and are largely disabled with this
iterator. Only the first iteration of an iterator instantiated with
mainSlot=True will get an index, subsequent iterations will get None (thus
removing the tabindex attribute).
"""
__allow_access_to_unprotected_subobjects__ = 1
def __init__(self, upper=100000, pos=0, mainSlot=True):
self.upper=upper
self.pos=pos
self.mainSlot=mainSlot
if not mainSlot:
self.disabled = True
else:
self.disabled = False
def next(self):
if self.disabled:
return None
self.disabled = True
return self.pos
class ToolInit(CMFCoreToolInit):
def getProductContext(self, context):
name = '_ProductContext__prod'
return getattr(context, name, getattr(context, '__prod', None))
def getPack(self, context):
name = '_ProductContext__pack'
return getattr(context, name, getattr(context, '__pack__', None))
def getIcon(self, context, path):
pack = self.getPack(context)
icon = None
# This variable is just used for the log message
icon_path = path
try:
icon = Globals.ImageFile(path, pack.__dict__)
except (IOError, OSError):
# Fallback:
# Assume path is relative to CMFPlone directory
path = abspath(join(PACKAGE_HOME, path))
try:
icon = Globals.ImageFile(path, pack.__dict__)
except (IOError, OSError):
# if there is some problem loading the fancy image
# from the tool then tell someone about it
log(('The icon for the product: %s which was set to: %s, '
'was not found. Using the default.' %
(self.product_name, icon_path)))
return icon
def initialize(self, context):
""" Wrap the CMFCore Tool Init method """
CMFCoreToolInit.initialize(self, context)
for tool in self.tools:
# Get the icon path from the tool
path = getattr(tool, 'toolicon', None)
if path is not None:
pc = self.getProductContext(context)
if pc is not None:
pid = pc.id
name = split(path)[1]
icon = self.getIcon(context, path)
if icon is None:
# Icon was not found
return
icon.__roles__ = None
tool.icon = 'misc_/%s/%s' % (self.product_name, name)
misc = OFS.misc_.misc_
Misc = OFS.misc_.Misc_
if not hasattr(misc, pid):
setattr(misc, pid, Misc(pid, {}))
getattr(misc, pid)[name] = icon
def _createObjectByType(type_name, container, id, *args, **kw):
"""Create an object without performing security checks
invokeFactory and fti.constructInstance perform some security checks
before creating the object. Use this function instead if you need to
skip these checks.
This method uses some code from
CMFCore.TypesTool.FactoryTypeInformation.constructInstance
to create the object without security checks.
"""
id = str(id)
typesTool = getToolByName(container, 'portal_types')
fti = typesTool.getTypeInfo(type_name)
if not fti:
raise ValueError, 'Invalid type %s' % type_name
# we have to do it all manually :(
p = container.manage_addProduct[fti.product]
m = getattr(p, fti.factory, None)
if m is None:
raise ValueError, ('Product factory for %s was invalid' %
fti.getId())
# construct the object
m(id, *args, **kw)
ob = container._getOb( id )
return fti._finishConstruction(ob)
def safeToInt(value):
"""Convert value to integer or just return 0 if we can't"""
try:
return int(value)
except ValueError:
return 0
release_levels = ('alpha', 'beta', 'candidate', 'final')
rl_abbr = {'a':'alpha', 'b':'beta', 'rc':'candidate'}
def versionTupleFromString(v_str):
"""Returns version tuple from passed in version string"""
regex_str = "(^\d+)[.]?(\d*)[.]?(\d*)[- ]?(alpha|beta|candidate|final|a|b|rc)?(\d*)"
v_regex = re.compile(regex_str)
match = v_regex.match(v_str)
if match is None:
v_tpl = None
else:
groups = list(match.groups())
for i in (0, 1, 2, 4):
groups[i] = safeToInt(groups[i])
if groups[3] is None:
groups[3] = 'final'
elif groups[3] in rl_abbr.keys():
groups[3] = rl_abbr[groups[3]]
v_tpl = tuple(groups)
return v_tpl
def getFSVersionTuple():
"""Reads version.txt and returns version tuple"""
vfile = "%s/version.txt" % PACKAGE_HOME
v_str = open(vfile, 'r').read().lower()
return versionTupleFromString(v_str)
def transaction_note(note):
"""Write human legible note"""
T=transaction.get()
if isinstance(note, unicode):
# Convert unicode to a regular string for the backend write IO.
# UTF-8 is the only reasonable choice, as using unicode means
# that Latin-1 is probably not enough.
note = note.encode('utf-8', 'replace')
if (len(T.description)+len(note))>=65535:
log('Transaction note too large omitting %s' % str(note))
else:
T.note(str(note))
def base_hasattr(obj, name):
"""Like safe_hasattr, but also disables acquisition."""
return safe_hasattr(aq_base(obj), name)
def safe_hasattr(obj, name, _marker=object()):
"""Make sure we don't mask exceptions like hasattr().
We don't want exceptions other than AttributeError to be masked,
since that too often masks other programming errors.
Three-argument getattr() doesn't mask those, so we use that to
implement our own hasattr() replacement.
"""
return getattr(obj, name, _marker) is not _marker
def safe_callable(obj):
"""Make sure our callable checks are ConflictError safe."""
if safe_hasattr(obj, '__class__'):
if safe_hasattr(obj, '__call__'):
return True
else:
return isinstance(obj, ClassType)
else:
return callable(obj)
def safe_unicode(value, encoding='utf-8'):
"""Converts a value to unicode, even it is already a unicode string.
>>> from Products.CMFPlone.utils import safe_unicode
>>> safe_unicode('spam')
u'spam'
>>> safe_unicode(u'spam')
u'spam'
>>> safe_unicode(u'spam'.encode('utf-8'))
u'spam'
>>> safe_unicode('\xc6\xb5')
u'\u01b5'
>>> safe_unicode(u'\xc6\xb5'.encode('iso-8859-1'))
u'\u01b5'
>>> safe_unicode('\xc6\xb5', encoding='ascii')
u'\u01b5'
>>> safe_unicode(1)
1
>>> print safe_unicode(None)
None
"""
if isinstance(value, unicode):
return value
elif isinstance(value, basestring):
try:
value = unicode(value, encoding)
except (UnicodeDecodeError):
value = value.decode('utf-8', 'replace')
return value
def tuplize(value):
if isinstance(value, tuple):
return value
if isinstance(value, list):
return tuple(value)
return (value,)
def _detuplize(interfaces, append):
if isinstance(interfaces, (tuple, list)):
for sub in interfaces:
_detuplize(sub, append)
else:
append(interfaces)
def flatten(interfaces):
flattened = []
_detuplize(interfaces, flattened.append)
return tuple(flattened)
def directlyProvides(obj, *interfaces):
# convert any Zope 2 interfaces to Zope 3 using fromZ2Interface
interfaces = flatten(interfaces)
normalized_interfaces = []
for i in interfaces:
try:
i = fromZ2Interface(i)
except ValueError: # already a Zope 3 interface
pass
assert issubclass(i, zope.interface.Interface)
normalized_interfaces.append(i)
return zope.interface.directlyProvides(obj, *normalized_interfaces)
def classImplements(class_, *interfaces):
# convert any Zope 2 interfaces to Zope 3 using fromZ2Interface
interfaces = flatten(interfaces)
normalized_interfaces = []
for i in interfaces:
try:
i = fromZ2Interface(i)
except ValueError: # already a Zope 3 interface
pass
assert issubclass(i, zope.interface.Interface)
normalized_interfaces.append(i)
return zope.interface.classImplements(class_, *normalized_interfaces)
def classDoesNotImplement(class_, *interfaces):
# convert any Zope 2 interfaces to Zope 3 using fromZ2Interface
interfaces = flatten(interfaces)
normalized_interfaces = []
for i in interfaces:
try:
i = fromZ2Interface(i)
except ValueError: # already a Zope 3 interface
pass
assert issubclass(i, zope.interface.Interface)
normalized_interfaces.append(i)
implemented = implementedBy(class_)
for iface in normalized_interfaces:
implemented = implemented - iface
return zope.interface.classImplementsOnly(class_, implemented)
def webdav_enabled(obj, container):
"""WebDAV check used in externalEditorEnabled.py"""
# Object implements lock interface
interface_tool = getToolByName(container, 'portal_interface')
if not interface_tool.objectImplements(obj, 'webdav.WriteLockInterface.WriteLockInterface'):
return False
# Backwards compatibility code for AT < 1.3.6
if safe_hasattr(obj, '__dav_marshall__'):
if obj.__dav_marshall__ == False:
return False
return True
# Copied 'unrestricted_rename' from ATCT migrations to avoid
# a dependency.
from App.Dialogs import MessageDialog
from OFS.CopySupport import CopyContainer
from OFS.CopySupport import CopyError
from OFS.CopySupport import eNotSupported
from cgi import escape
import sys
def _unrestricted_rename(container, id, new_id):
"""Rename a particular sub-object
Copied from OFS.CopySupport
Less strict version of manage_renameObject:
* no write lock check
* no verify object check from PortalFolder so it's allowed to rename
even unallowed portal types inside a folder
"""
try: container._checkId(new_id)
except: raise CopyError, MessageDialog(
title='Invalid Id',
message=sys.exc_info()[1],
action ='manage_main')
ob=container._getOb(id)
#!#if ob.wl_isLocked():
#!# raise ResourceLockedError, 'Object "%s" is locked via WebDAV' % ob.getId()
if not ob.cb_isMoveable():
raise CopyError, eNotSupported % escape(id)
#!#container._verifyObjectPaste(ob)
#!#CopyContainer._verifyObjectPaste(container, ob)
try: ob._notifyOfCopyTo(container, op=1)
except: raise CopyError, MessageDialog(
title='Rename Error',
message=sys.exc_info()[1],
action ='manage_main')
container._delObject(id)
ob = aq_base(ob)
ob._setId(new_id)
# Note - because a rename always keeps the same context, we
# can just leave the ownership info unchanged.
container._setObject(new_id, ob, set_owner=0)
ob = container._getOb(new_id)
ob._postCopy(container, op=1)
#!#if REQUEST is not None:
#!# return container.manage_main(container, REQUEST, update_menu=1)
return None
# Copied '_getSecurity' from Archetypes.utils to avoid a dependency.
from AccessControl import ClassSecurityInfo
def _getSecurity(klass, create=True):
# a Zope 2 class can contain some attribute that is an instance
# of ClassSecurityInfo. Zope 2 scans through things looking for
# an attribute that has the name __security_info__ first
info = vars(klass)
security = None
for k, v in info.items():
if hasattr(v, '__security_info__'):
security = v
break
# Didn't found a ClassSecurityInfo object
if security is None:
if not create:
return None
# we stuff the name ourselves as __security__, not security, as this
# could theoretically lead to name clashes, and doesn't matter for
# zope 2 anyway.
security = ClassSecurityInfo()
setattr(klass, '__security__', security)
return security
def scale_image(image_file, max_size=None, default_format=None):
"""Scales an image down to at most max_size preserving aspect ratio
from an input file
>>> import Products.CMFPlone
>>> import os
>>> from StringIO import StringIO
>>> from Products.CMFPlone.utils import scale_image
>>> from PIL import Image
Let's make a couple test images and see how it works (all are
100x100), the gif is palletted mode::
>>> plone_path = os.path.dirname(Products.CMFPlone.__file__)
>>> pjoin = os.path.join
>>> path = pjoin(plone_path, 'tests', 'images')
>>> orig_jpg = open(pjoin(path, 'test.jpg'))
>>> orig_png = open(pjoin(path, 'test.png'))
>>> orig_gif = open(pjoin(path, 'test.gif'))
We'll also make some evil non-images, including one which
masquerades as a jpeg (which would trick OFS.Image)::
>>> invalid = StringIO('<div>Evil!!!</div>')
>>> sneaky = StringIO('\377\330<div>Evil!!!</div>')
OK, let's get to it, first check that our bad images fail:
>>> scale_image(invalid, (50, 50))
Traceback (most recent call last):
...
IOError: cannot identify image file
>>> scale_image(sneaky, (50, 50))
Traceback (most recent call last):
...
IOError: cannot identify image file
Now that that's out of the way we check on our real images to make
sure the format and mode are preserved, that they are scaled, and that they
return the correct mimetype::
>>> new_jpg, mimetype = scale_image(orig_jpg, (50, 50))
>>> img = Image.open(new_jpg)
>>> img.size
(50, 50)
>>> img.format
'JPEG'
>>> mimetype
'image/jpeg'
>>> new_png, mimetype = scale_image(orig_png, (50, 50))
>>> img = Image.open(new_png)
>>> img.size
(50, 50)
>>> img.format
'PNG'
>>> mimetype
'image/png'
>>> new_gif, mimetype = scale_image(orig_gif, (50, 50))
>>> img = Image.open(new_gif)
>>> img.size
(50, 50)
>>> img.format
'GIF'
>>> img.mode
'P'
>>> mimetype
'image/gif'
We should also preserve the aspect ratio by scaling to the given
width only unless told not to (we need to reset out files before
trying again though::
>>> orig_jpg.seek(0)
>>> new_jpg, mimetype = scale_image(orig_jpg, (70, 100))
>>> img = Image.open(new_jpg)
>>> img.size
(70, 70)
>>> orig_jpg.seek(0)
>>> new_jpg, mimetype = scale_image(orig_jpg, (70, 50))
>>> img = Image.open(new_jpg)
>>> img.size
(50, 50)
"""
if max_size is None:
max_size = IMAGE_SCALE_PARAMS['scale']
if default_format is None:
default_format = IMAGE_SCALE_PARAMS['default_format']
# Make sure we have ints
size = (int(max_size[0]), int(max_size[1]))
# Load up the image, don't try to catch errors, we want to fail miserably
# on invalid images
image = Image.open(image_file)
# When might image.format not be true?
format = image.format
mimetype = 'image/%s'%format.lower()
cur_size = image.size
# from Archetypes ImageField
# consider image mode when scaling
# source images can be mode '1','L,','P','RGB(A)'
# convert to greyscale or RGBA before scaling
# preserve palletted mode (but not pallette)
# for palletted-only image formats, e.g. GIF
# PNG compression is OK for RGBA thumbnails
original_mode = image.mode
if original_mode == '1':
image = image.convert('L')
elif original_mode == 'P':
image = image.convert('RGBA')
# Rescale in place with an method that will not alter the aspect ratio
# and will only shrink the image not enlarge it.
image.thumbnail(size, resample=IMAGE_SCALE_PARAMS['algorithm'])
# preserve palletted mode for GIF and PNG
if original_mode == 'P' and format in ('GIF', 'PNG'):
image = image.convert('P')
# Save
new_file = StringIO()
image.save(new_file, format, quality=IMAGE_SCALE_PARAMS['quality'])
new_file.seek(0)
# Return the file data and the new mimetype
return new_file, mimetype
# Keep these here to not fully change the old API
# Put these at the end to avoid an ImportError for safe_unicode
from i18nl10n import utranslate
from i18nl10n import ulocalized_time
from i18nl10n import getGlobalTranslationService