# template.py
# Copyright (C) 2006, 2007, 2008, 2009, 2010 Michael Bayer
# mike_mp@zzzcomputing.com
#
# This module is part of Mako and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php
"""Provides the Template class, a facade for parsing, generating and executing
template strings, as well as template runtime operations."""
from mako.lexer import Lexer
from mako import runtime,util,exceptions,codegen
import imp, os, re, shutil, stat, sys, tempfile, time, types, weakref
class Template(object):
"""a compiled template"""
def __init__(self,
text=None,
filename=None,
uri=None,
format_exceptions=False,
error_handler=None,
lookup=None,
output_encoding=None,
encoding_errors='strict',
module_directory=None,
cache_type=None,
cache_dir=None,
cache_url=None,
module_filename=None,
input_encoding=None,
disable_unicode=False,
default_filters=None,
buffer_filters=(),
imports=None,
preprocessor=None,
cache_enabled=True):
"""Construct a new Template instance using either literal template
text, or a previously loaded template module
:param text: textual template source, or None if a module is to be
provided
:param uri: the uri of this template, or some identifying string.
defaults to the full filename given, or "memory:(hex id of this
Template)" if no filename
:param filename: filename of the source template, if any
:param format_exceptions: catch exceptions and format them into an
error display template
"""
if uri:
self.module_id = re.sub(r'\W', "_", uri)
self.uri = uri
elif filename:
self.module_id = re.sub(r'\W', "_", filename)
drive, path = os.path.splitdrive(filename)
path = os.path.normpath(path).replace(os.path.sep, "/")
self.uri = path
else:
self.module_id = "memory:" + hex(id(self))
self.uri = self.module_id
self.input_encoding = input_encoding
self.output_encoding = output_encoding
self.encoding_errors = encoding_errors
self.disable_unicode = disable_unicode
if util.py3k and disable_unicode:
raise exceptions.UnsupportedError(
"Mako for Python 3 does not "
"support disabling Unicode")
if default_filters is None:
if util.py3k or self.disable_unicode:
self.default_filters = ['str']
else:
self.default_filters = ['unicode']
else:
self.default_filters = default_filters
self.buffer_filters = buffer_filters
self.imports = imports
self.preprocessor = preprocessor
# if plain text, compile code in memory only
if text is not None:
(code, module) = _compile_text(self, text, filename)
self._code = code
self._source = text
ModuleInfo(module, None, self, filename, code, text)
elif filename is not None:
# if template filename and a module directory, load
# a filesystem-based module file, generating if needed
if module_filename is not None:
path = module_filename
elif module_directory is not None:
u = self.uri
if u[0] == '/':
u = u[1:]
path = os.path.abspath(
os.path.join(
os.path.normpath(module_directory),
os.path.normpath(u) + ".py"
)
)
else:
path = None
module = self._compile_from_file(path, filename)
else:
raise exceptions.RuntimeException(
"Template requires text or filename")
self.module = module
self.filename = filename
self.callable_ = self.module.render_body
self.format_exceptions = format_exceptions
self.error_handler = error_handler
self.lookup = lookup
self.cache_type = cache_type
self.cache_dir = cache_dir
self.cache_url = cache_url
self.cache_enabled = cache_enabled
def _compile_from_file(self, path, filename):
if path is not None:
util.verify_directory(os.path.dirname(path))
filemtime = os.stat(filename)[stat.ST_MTIME]
if not os.path.exists(path) or \
os.stat(path)[stat.ST_MTIME] < filemtime:
_compile_module_file(
self,
open(filename, 'rb').read(),
filename,
path)
module = imp.load_source(self.module_id, path, open(path, 'rb'))
del sys.modules[self.module_id]
if module._magic_number != codegen.MAGIC_NUMBER:
_compile_module_file(
self,
open(filename, 'rb').read(),
filename,
path)
module = imp.load_source(self.module_id, path, open(path, 'rb'))
del sys.modules[self.module_id]
ModuleInfo(module, path, self, filename, None, None)
else:
# template filename and no module directory, compile code
# in memory
code, module = _compile_text(
self,
open(filename, 'rb').read(),
filename)
self._source = None
self._code = code
ModuleInfo(module, None, self, filename, code, None)
return module
@property
def source(self):
"""return the template source code for this Template."""
return _get_module_info_from_callable(self.callable_).source
@property
def code(self):
"""return the module source code for this Template"""
return _get_module_info_from_callable(self.callable_).code
@property
def cache(self):
return self.module._template_cache
def render(self, *args, **data):
"""Render the output of this template as a string.
if the template specifies an output encoding, the string will be
encoded accordingly, else the output is raw (raw output uses cStringIO
and can't handle multibyte characters). a Context object is created
corresponding to the given data. Arguments that are explictly declared
by this template's internal rendering method are also pulled from the
given \*args, \**data members.
"""
return runtime._render(self, self.callable_, args, data)
def render_unicode(self, *args, **data):
"""render the output of this template as a unicode object."""
return runtime._render(self,
self.callable_,
args,
data,
as_unicode=True)
def render_context(self, context, *args, **kwargs):
"""Render this Template with the given context.
the data is written to the context's buffer.
"""
if getattr(context, '_with_template', None) is None:
context._with_template = self
runtime._render_context(self,
self.callable_,
context,
*args,
**kwargs)
def has_def(self, name):
return hasattr(self.module, "render_%s" % name)
def get_def(self, name):
"""Return a def of this template as a DefTemplate."""
return DefTemplate(self, getattr(self.module, "render_%s" % name))
def _get_def_callable(self, name):
return getattr(self.module, "render_%s" % name)
@property
def last_modified(self):
return self.module._modified_time
last_modified = property(last_modified)
class ModuleTemplate(Template):
"""A Template which is constructed given an existing Python module.
e.g.::
t = Template("this is a template")
f = file("mymodule.py", "w")
f.write(t.code)
f.close()
import mymodule
t = ModuleTemplate(mymodule)
print t.render()
"""
def __init__(self, module,
module_filename=None,
template=None,
template_filename=None,
module_source=None,
template_source=None,
output_encoding=None,
encoding_errors='strict',
disable_unicode=False,
format_exceptions=False,
error_handler=None,
lookup=None,
cache_type=None,
cache_dir=None,
cache_url=None,
cache_enabled=True
):
self.module_id = re.sub(r'\W', "_", module._template_uri)
self.uri = module._template_uri
self.input_encoding = module._source_encoding
self.output_encoding = output_encoding
self.encoding_errors = encoding_errors
self.disable_unicode = disable_unicode
self.module = module
self.filename = template_filename
ModuleInfo(module,
module_filename,
self,
template_filename,
module_source,
template_source)
self.callable_ = self.module.render_body
self.format_exceptions = format_exceptions
self.error_handler = error_handler
self.lookup = lookup
self.cache_type = cache_type
self.cache_dir = cache_dir
self.cache_url = cache_url
self.cache_enabled = cache_enabled
class DefTemplate(Template):
"""a Template which represents a callable def in a parent template."""
def __init__(self, parent, callable_):
self.parent = parent
self.callable_ = callable_
self.output_encoding = parent.output_encoding
self.module = parent.module
self.encoding_errors = parent.encoding_errors
self.format_exceptions = parent.format_exceptions
self.error_handler = parent.error_handler
self.lookup = parent.lookup
def get_def(self, name):
return self.parent.get_def(name)
class ModuleInfo(object):
"""Stores information about a module currently loaded into memory,
provides reverse lookups of template source, module source code based on
a module's identifier.
"""
_modules = weakref.WeakValueDictionary()
def __init__(self,
module,
module_filename,
template,
template_filename,
module_source,
template_source):
self.module = module
self.module_filename = module_filename
self.template_filename = template_filename
self.module_source = module_source
self.template_source = template_source
self._modules[module.__name__] = template._mmarker = self
if module_filename:
self._modules[module_filename] = self
@property
def code(self):
if self.module_source is not None:
return self.module_source
else:
return open(self.module_filename).read()
@property
def source(self):
if self.template_source is not None:
if self.module._source_encoding and \
not isinstance(self.template_source, unicode):
return self.template_source.decode(
self.module._source_encoding)
else:
return self.template_source
else:
if self.module._source_encoding:
return open(self.template_filename, 'rb').read().\
decode(self.module._source_encoding)
else:
return open(self.template_filename).read()
def _compile_text(template, text, filename):
identifier = template.module_id
lexer = Lexer(text,
filename,
disable_unicode=template.disable_unicode,
input_encoding=template.input_encoding,
preprocessor=template.preprocessor)
node = lexer.parse()
source = codegen.compile(node,
template.uri,
filename,
default_filters=template.default_filters,
buffer_filters=template.buffer_filters,
imports=template.imports,
source_encoding=lexer.encoding,
generate_magic_comment=template.disable_unicode)
cid = identifier
if not util.py3k and isinstance(cid, unicode):
cid = cid.encode()
module = types.ModuleType(cid)
code = compile(source, cid, 'exec')
exec code in module.__dict__, module.__dict__
return (source, module)
def _compile_module_file(template, text, filename, outputpath):
identifier = template.module_id
lexer = Lexer(text,
filename,
disable_unicode=template.disable_unicode,
input_encoding=template.input_encoding,
preprocessor=template.preprocessor)
node = lexer.parse()
source = codegen.compile(node,
template.uri,
filename,
default_filters=template.default_filters,
buffer_filters=template.buffer_filters,
imports=template.imports,
source_encoding=lexer.encoding,
generate_magic_comment=True)
(dest, name) = tempfile.mkstemp()
if isinstance(source, unicode):
source = source.encode(lexer.encoding or 'ascii')
os.write(dest, source)
os.close(dest)
shutil.move(name, outputpath)
def _get_module_info_from_callable(callable_):
return _get_module_info(callable_.func_globals['__name__'])
def _get_module_info(filename):
return ModuleInfo._modules[filename]
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