def validate(self, value, adapt=True):
if value in ['', None] and self.nullable:
return ''
super(UTF8, self).validate(value)
for c in self.must_contain:
if c not in value:
raise ValidationError(
('Invalid email address {}. '
'A valid email address must contain at least '
'one @ characters'.format(str(value)))
)
return force_utf8(value)
def math_to_image(self, s, filename_or_obj, color='black', dpi=None, fontsize=10):
"""
This function is a thread safe modification of matplotlib's
mathtext:math_to_image. The MathTextParser render's font caching
mechanism makes it impossible to use with multiple threads.
Thus we first have to acquire a lock from matplotlib RendererAgg and
block other threads from entering render while it's in process.
Given a math expression, renders it in a closely-clipped bounding
box to an image file.
*s*
A math expression. The math portion should be enclosed in
dollar signs.
*filename_or_obj*
A filepath or writable file-like object to write the image data
to.
*color*
Text color
*dpi*
Override the output dpi, otherwise use the default associated
with the output format.
*fontsize*
The font size, defaults to 10.
"""
try:
s = unicode(s)
except UnicodeDecodeError:
s = unicode(filters.force_utf8(s).decode('utf-8'))
RendererAgg.lock.acquire()
try:
self.math_text_parser.to_png(filename_or_obj, s, color=color, dpi=dpi, fontsize=fontsize)
except (ParseFatalException, AttributeError):
# Probably some invalid arguments supplied for math parser
# We can most likely ignore them
pass
finally:
RendererAgg.lock.release()
def _normalize(self, text):
return filters.force_utf8(' '.join(text.strip(' \t').split()))
