You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
bazarr/libs/jinja2/environment.py

1662 lines
60 KiB

"""Classes for managing templates and their runtime and compile time
options.
5 years ago
"""
import os
import sys
import typing
import typing as t
5 years ago
import weakref
from collections import ChainMap
from functools import lru_cache
from functools import partial
from functools import reduce
from types import CodeType
from markupsafe import Markup
from . import nodes
from .compiler import CodeGenerator
from .compiler import generate
from .defaults import BLOCK_END_STRING
from .defaults import BLOCK_START_STRING
from .defaults import COMMENT_END_STRING
from .defaults import COMMENT_START_STRING
from .defaults import DEFAULT_FILTERS
from .defaults import DEFAULT_NAMESPACE
from .defaults import DEFAULT_POLICIES
from .defaults import DEFAULT_TESTS
from .defaults import KEEP_TRAILING_NEWLINE
from .defaults import LINE_COMMENT_PREFIX
from .defaults import LINE_STATEMENT_PREFIX
from .defaults import LSTRIP_BLOCKS
from .defaults import NEWLINE_SEQUENCE
from .defaults import TRIM_BLOCKS
from .defaults import VARIABLE_END_STRING
from .defaults import VARIABLE_START_STRING
from .exceptions import TemplateNotFound
from .exceptions import TemplateRuntimeError
from .exceptions import TemplatesNotFound
from .exceptions import TemplateSyntaxError
from .exceptions import UndefinedError
from .lexer import get_lexer
from .lexer import Lexer
from .lexer import TokenStream
from .nodes import EvalContext
from .parser import Parser
from .runtime import Context
from .runtime import new_context
from .runtime import Undefined
from .utils import _PassArg
from .utils import concat
from .utils import consume
from .utils import import_string
from .utils import internalcode
from .utils import LRUCache
from .utils import missing
if t.TYPE_CHECKING:
import typing_extensions as te
from .bccache import BytecodeCache
from .ext import Extension
from .loaders import BaseLoader
_env_bound = t.TypeVar("_env_bound", bound="Environment")
5 years ago
# for direct template usage we have up to ten living environments
@lru_cache(maxsize=10)
def get_spontaneous_environment(cls: t.Type[_env_bound], *args: t.Any) -> _env_bound:
"""Return a new spontaneous environment. A spontaneous environment
is used for templates created directly rather than through an
existing environment.
:param cls: Environment class to create.
:param args: Positional arguments passed to environment.
5 years ago
"""
env = cls(*args)
5 years ago
env.shared = True
return env
def create_cache(
size: int,
) -> t.Optional[t.MutableMapping[t.Tuple[weakref.ref, str], "Template"]]:
5 years ago
"""Return the cache class for the given size."""
if size == 0:
return None
5 years ago
if size < 0:
return {}
return LRUCache(size) # type: ignore
5 years ago
def copy_cache(
cache: t.Optional[t.MutableMapping],
) -> t.Optional[t.MutableMapping[t.Tuple[weakref.ref, str], "Template"]]:
5 years ago
"""Create an empty copy of the given cache."""
if cache is None:
return None
if type(cache) is dict:
5 years ago
return {}
return LRUCache(cache.capacity) # type: ignore
5 years ago
def load_extensions(
environment: "Environment",
extensions: t.Sequence[t.Union[str, t.Type["Extension"]]],
) -> t.Dict[str, "Extension"]:
5 years ago
"""Load the extensions from the list and bind it to the environment.
Returns a dict of instantiated extensions.
5 years ago
"""
result = {}
5 years ago
for extension in extensions:
if isinstance(extension, str):
extension = t.cast(t.Type["Extension"], import_string(extension))
5 years ago
result[extension.identifier] = extension(environment)
5 years ago
return result
5 years ago
def _environment_config_check(environment: "Environment") -> "Environment":
5 years ago
"""Perform a sanity check on the environment."""
assert issubclass(
environment.undefined, Undefined
), "'undefined' must be a subclass of 'jinja2.Undefined'."
assert (
environment.block_start_string
!= environment.variable_start_string
!= environment.comment_start_string
), "block, variable and comment start strings must be different."
assert environment.newline_sequence in {
"\r",
"\r\n",
"\n",
}, "'newline_sequence' must be one of '\\n', '\\r\\n', or '\\r'."
5 years ago
return environment
class Environment:
5 years ago
r"""The core component of Jinja is the `Environment`. It contains
important shared variables like configuration, filters, tests,
globals and others. Instances of this class may be modified if
they are not shared and if no template was loaded so far.
Modifications on environments after the first template was loaded
will lead to surprising effects and undefined behavior.
Here are the possible initialization parameters:
`block_start_string`
The string marking the beginning of a block. Defaults to ``'{%'``.
`block_end_string`
The string marking the end of a block. Defaults to ``'%}'``.
`variable_start_string`
The string marking the beginning of a print statement.
Defaults to ``'{{'``.
`variable_end_string`
The string marking the end of a print statement. Defaults to
``'}}'``.
`comment_start_string`
The string marking the beginning of a comment. Defaults to ``'{#'``.
`comment_end_string`
The string marking the end of a comment. Defaults to ``'#}'``.
`line_statement_prefix`
If given and a string, this will be used as prefix for line based
statements. See also :ref:`line-statements`.
`line_comment_prefix`
If given and a string, this will be used as prefix for line based
comments. See also :ref:`line-statements`.
.. versionadded:: 2.2
`trim_blocks`
If this is set to ``True`` the first newline after a block is
removed (block, not variable tag!). Defaults to `False`.
`lstrip_blocks`
If this is set to ``True`` leading spaces and tabs are stripped
from the start of a line to a block. Defaults to `False`.
`newline_sequence`
The sequence that starts a newline. Must be one of ``'\r'``,
``'\n'`` or ``'\r\n'``. The default is ``'\n'`` which is a
useful default for Linux and OS X systems as well as web
applications.
`keep_trailing_newline`
Preserve the trailing newline when rendering templates.
The default is ``False``, which causes a single newline,
if present, to be stripped from the end of the template.
.. versionadded:: 2.7
`extensions`
List of Jinja extensions to use. This can either be import paths
as strings or extension classes. For more information have a
look at :ref:`the extensions documentation <jinja-extensions>`.
`optimized`
should the optimizer be enabled? Default is ``True``.
`undefined`
:class:`Undefined` or a subclass of it that is used to represent
undefined values in the template.
`finalize`
A callable that can be used to process the result of a variable
expression before it is output. For example one can convert
``None`` implicitly into an empty string here.
`autoescape`
If set to ``True`` the XML/HTML autoescaping feature is enabled by
default. For more details about autoescaping see
:class:`~markupsafe.Markup`. As of Jinja 2.4 this can also
5 years ago
be a callable that is passed the template name and has to
return ``True`` or ``False`` depending on autoescape should be
enabled by default.
.. versionchanged:: 2.4
`autoescape` can now be a function
`loader`
The template loader for this environment.
`cache_size`
The size of the cache. Per default this is ``400`` which means
that if more than 400 templates are loaded the loader will clean
out the least recently used template. If the cache size is set to
``0`` templates are recompiled all the time, if the cache size is
``-1`` the cache will not be cleaned.
.. versionchanged:: 2.8
The cache size was increased to 400 from a low 50.
`auto_reload`
Some loaders load templates from locations where the template
sources may change (ie: file system or database). If
``auto_reload`` is set to ``True`` (default) every time a template is
requested the loader checks if the source changed and if yes, it
will reload the template. For higher performance it's possible to
disable that.
`bytecode_cache`
If set to a bytecode cache object, this object will provide a
cache for the internal Jinja bytecode so that templates don't
have to be parsed if they were not changed.
See :ref:`bytecode-cache` for more information.
`enable_async`
If set to true this enables async template execution which
allows using async functions and generators.
5 years ago
"""
#: if this environment is sandboxed. Modifying this variable won't make
#: the environment sandboxed though. For a real sandboxed environment
#: have a look at jinja2.sandbox. This flag alone controls the code
#: generation by the compiler.
sandboxed = False
#: True if the environment is just an overlay
overlayed = False
#: the environment this environment is linked to if it is an overlay
linked_to: t.Optional["Environment"] = None
5 years ago
#: shared environments have this set to `True`. A shared environment
#: must not be modified
shared = False
#: the class that is used for code generation. See
#: :class:`~jinja2.compiler.CodeGenerator` for more information.
code_generator_class: t.Type["CodeGenerator"] = CodeGenerator
5 years ago
#: the context class that is used for templates. See
5 years ago
#: :class:`~jinja2.runtime.Context` for more information.
context_class: t.Type[Context] = Context
template_class: t.Type["Template"]
def __init__(
self,
block_start_string: str = BLOCK_START_STRING,
block_end_string: str = BLOCK_END_STRING,
variable_start_string: str = VARIABLE_START_STRING,
variable_end_string: str = VARIABLE_END_STRING,
comment_start_string: str = COMMENT_START_STRING,
comment_end_string: str = COMMENT_END_STRING,
line_statement_prefix: t.Optional[str] = LINE_STATEMENT_PREFIX,
line_comment_prefix: t.Optional[str] = LINE_COMMENT_PREFIX,
trim_blocks: bool = TRIM_BLOCKS,
lstrip_blocks: bool = LSTRIP_BLOCKS,
newline_sequence: "te.Literal['\\n', '\\r\\n', '\\r']" = NEWLINE_SEQUENCE,
keep_trailing_newline: bool = KEEP_TRAILING_NEWLINE,
extensions: t.Sequence[t.Union[str, t.Type["Extension"]]] = (),
optimized: bool = True,
undefined: t.Type[Undefined] = Undefined,
finalize: t.Optional[t.Callable[..., t.Any]] = None,
autoescape: t.Union[bool, t.Callable[[t.Optional[str]], bool]] = False,
loader: t.Optional["BaseLoader"] = None,
cache_size: int = 400,
auto_reload: bool = True,
bytecode_cache: t.Optional["BytecodeCache"] = None,
enable_async: bool = False,
):
5 years ago
# !!Important notice!!
# The constructor accepts quite a few arguments that should be
# passed by keyword rather than position. However it's important to
# not change the order of arguments because it's used at least
# internally in those cases:
# - spontaneous environments (i18n extension and Template)
# - unittests
# If parameter changes are required only add parameters at the end
# and don't change the arguments (or the defaults!) of the arguments
# existing already.
# lexer / parser information
self.block_start_string = block_start_string
self.block_end_string = block_end_string
self.variable_start_string = variable_start_string
self.variable_end_string = variable_end_string
self.comment_start_string = comment_start_string
self.comment_end_string = comment_end_string
self.line_statement_prefix = line_statement_prefix
self.line_comment_prefix = line_comment_prefix
self.trim_blocks = trim_blocks
self.lstrip_blocks = lstrip_blocks
self.newline_sequence = newline_sequence
self.keep_trailing_newline = keep_trailing_newline
# runtime information
self.undefined: t.Type[Undefined] = undefined
5 years ago
self.optimized = optimized
self.finalize = finalize
self.autoescape = autoescape
# defaults
self.filters = DEFAULT_FILTERS.copy()
self.tests = DEFAULT_TESTS.copy()
self.globals = DEFAULT_NAMESPACE.copy()
# set the loader provided
self.loader = loader
self.cache = create_cache(cache_size)
self.bytecode_cache = bytecode_cache
self.auto_reload = auto_reload
# configurable policies
self.policies = DEFAULT_POLICIES.copy()
# load extensions
self.extensions = load_extensions(self, extensions)
self.is_async = enable_async
_environment_config_check(self)
5 years ago
def add_extension(self, extension: t.Union[str, t.Type["Extension"]]) -> None:
5 years ago
"""Adds an extension after the environment was created.
.. versionadded:: 2.5
"""
self.extensions.update(load_extensions(self, [extension]))
def extend(self, **attributes: t.Any) -> None:
5 years ago
"""Add the items to the instance of the environment if they do not exist
yet. This is used by :ref:`extensions <writing-extensions>` to register
callbacks and configuration values without breaking inheritance.
"""
for key, value in attributes.items():
5 years ago
if not hasattr(self, key):
setattr(self, key, value)
def overlay(
self,
block_start_string: str = missing,
block_end_string: str = missing,
variable_start_string: str = missing,
variable_end_string: str = missing,
comment_start_string: str = missing,
comment_end_string: str = missing,
line_statement_prefix: t.Optional[str] = missing,
line_comment_prefix: t.Optional[str] = missing,
trim_blocks: bool = missing,
lstrip_blocks: bool = missing,
extensions: t.Sequence[t.Union[str, t.Type["Extension"]]] = missing,
optimized: bool = missing,
undefined: t.Type[Undefined] = missing,
finalize: t.Optional[t.Callable[..., t.Any]] = missing,
autoescape: t.Union[bool, t.Callable[[t.Optional[str]], bool]] = missing,
loader: t.Optional["BaseLoader"] = missing,
cache_size: int = missing,
auto_reload: bool = missing,
bytecode_cache: t.Optional["BytecodeCache"] = missing,
) -> "Environment":
5 years ago
"""Create a new overlay environment that shares all the data with the
current environment except for cache and the overridden attributes.
Extensions cannot be removed for an overlayed environment. An overlayed
environment automatically gets all the extensions of the environment it
is linked to plus optional extra extensions.
Creating overlays should happen after the initial environment was set
up completely. Not all attributes are truly linked, some are just
copied over so modifications on the original environment may not shine
through.
"""
args = dict(locals())
del args["self"], args["cache_size"], args["extensions"]
5 years ago
rv = object.__new__(self.__class__)
rv.__dict__.update(self.__dict__)
rv.overlayed = True
rv.linked_to = self
for key, value in args.items():
5 years ago
if value is not missing:
setattr(rv, key, value)
if cache_size is not missing:
rv.cache = create_cache(cache_size)
else:
rv.cache = copy_cache(self.cache)
rv.extensions = {}
for key, value in self.extensions.items():
5 years ago
rv.extensions[key] = value.bind(rv)
if extensions is not missing:
rv.extensions.update(load_extensions(rv, extensions))
return _environment_config_check(rv)
5 years ago
@property
def lexer(self) -> Lexer:
"""The lexer for this environment."""
return get_lexer(self)
5 years ago
def iter_extensions(self) -> t.Iterator["Extension"]:
5 years ago
"""Iterates over the extensions by priority."""
return iter(sorted(self.extensions.values(), key=lambda x: x.priority))
5 years ago
def getitem(
self, obj: t.Any, argument: t.Union[str, t.Any]
) -> t.Union[t.Any, Undefined]:
5 years ago
"""Get an item or attribute of an object but prefer the item."""
try:
return obj[argument]
except (AttributeError, TypeError, LookupError):
if isinstance(argument, str):
5 years ago
try:
attr = str(argument)
except Exception:
pass
else:
try:
return getattr(obj, attr)
except AttributeError:
pass
return self.undefined(obj=obj, name=argument)
def getattr(self, obj: t.Any, attribute: str) -> t.Any:
5 years ago
"""Get an item or attribute of an object but prefer the attribute.
Unlike :meth:`getitem` the attribute *must* be a string.
5 years ago
"""
try:
return getattr(obj, attribute)
except AttributeError:
pass
try:
return obj[attribute]
except (TypeError, LookupError, AttributeError):
return self.undefined(obj=obj, name=attribute)
def _filter_test_common(
self,
name: t.Union[str, Undefined],
value: t.Any,
args: t.Optional[t.Sequence[t.Any]],
kwargs: t.Optional[t.Mapping[str, t.Any]],
context: t.Optional[Context],
eval_ctx: t.Optional[EvalContext],
is_filter: bool,
) -> t.Any:
if is_filter:
env_map = self.filters
type_name = "filter"
else:
env_map = self.tests
type_name = "test"
5 years ago
func = env_map.get(name) # type: ignore
5 years ago
if func is None:
msg = f"No {type_name} named {name!r}."
if isinstance(name, Undefined):
try:
name._fail_with_undefined_error()
except Exception as e:
msg = f"{msg} ({e}; did you forget to quote the callable name?)"
raise TemplateRuntimeError(msg)
args = [value, *(args if args is not None else ())]
kwargs = kwargs if kwargs is not None else {}
pass_arg = _PassArg.from_obj(func)
if pass_arg is _PassArg.context:
5 years ago
if context is None:
raise TemplateRuntimeError(
f"Attempted to invoke a context {type_name} without context."
)
5 years ago
args.insert(0, context)
elif pass_arg is _PassArg.eval_context:
5 years ago
if eval_ctx is None:
if context is not None:
eval_ctx = context.eval_ctx
else:
eval_ctx = EvalContext(self)
5 years ago
args.insert(0, eval_ctx)
elif pass_arg is _PassArg.environment:
5 years ago
args.insert(0, self)
return func(*args, **kwargs)
def call_filter(
self,
name: str,
value: t.Any,
args: t.Optional[t.Sequence[t.Any]] = None,
kwargs: t.Optional[t.Mapping[str, t.Any]] = None,
context: t.Optional[Context] = None,
eval_ctx: t.Optional[EvalContext] = None,
) -> t.Any:
"""Invoke a filter on a value the same way the compiler does.
This might return a coroutine if the filter is running from an
environment in async mode and the filter supports async
execution. It's your responsibility to await this if needed.
5 years ago
.. versionadded:: 2.7
"""
return self._filter_test_common(
name, value, args, kwargs, context, eval_ctx, True
)
def call_test(
self,
name: str,
value: t.Any,
args: t.Optional[t.Sequence[t.Any]] = None,
kwargs: t.Optional[t.Mapping[str, t.Any]] = None,
context: t.Optional[Context] = None,
eval_ctx: t.Optional[EvalContext] = None,
) -> t.Any:
"""Invoke a test on a value the same way the compiler does.
This might return a coroutine if the test is running from an
environment in async mode and the test supports async execution.
It's your responsibility to await this if needed.
.. versionchanged:: 3.0
Tests support ``@pass_context``, etc. decorators. Added
the ``context`` and ``eval_ctx`` parameters.
.. versionadded:: 2.7
"""
return self._filter_test_common(
name, value, args, kwargs, context, eval_ctx, False
)
5 years ago
@internalcode
def parse(
self,
source: str,
name: t.Optional[str] = None,
filename: t.Optional[str] = None,
) -> nodes.Template:
5 years ago
"""Parse the sourcecode and return the abstract syntax tree. This
tree of nodes is used by the compiler to convert the template into
executable source- or bytecode. This is useful for debugging or to
extract information from templates.
If you are :ref:`developing Jinja extensions <writing-extensions>`
5 years ago
this gives you a good overview of the node tree generated.
"""
try:
return self._parse(source, name, filename)
except TemplateSyntaxError:
self.handle_exception(source=source)
5 years ago
def _parse(
self, source: str, name: t.Optional[str], filename: t.Optional[str]
) -> nodes.Template:
5 years ago
"""Internal parsing function used by `parse` and `compile`."""
return Parser(self, source, name, filename).parse()
def lex(
self,
source: str,
name: t.Optional[str] = None,
filename: t.Optional[str] = None,
) -> t.Iterator[t.Tuple[int, str, str]]:
5 years ago
"""Lex the given sourcecode and return a generator that yields
tokens as tuples in the form ``(lineno, token_type, value)``.
This can be useful for :ref:`extension development <writing-extensions>`
and debugging templates.
This does not perform preprocessing. If you want the preprocessing
of the extensions to be applied you have to filter source through
the :meth:`preprocess` method.
"""
source = str(source)
5 years ago
try:
return self.lexer.tokeniter(source, name, filename)
except TemplateSyntaxError:
self.handle_exception(source=source)
def preprocess(
self,
source: str,
name: t.Optional[str] = None,
filename: t.Optional[str] = None,
) -> str:
5 years ago
"""Preprocesses the source with all extensions. This is automatically
called for all parsing and compiling methods but *not* for :meth:`lex`
because there you usually only want the actual source tokenized.
"""
return reduce(
lambda s, e: e.preprocess(s, name, filename),
self.iter_extensions(),
str(source),
)
def _tokenize(
self,
source: str,
name: t.Optional[str],
filename: t.Optional[str] = None,
state: t.Optional[str] = None,
) -> TokenStream:
5 years ago
"""Called by the parser to do the preprocessing and filtering
for all the extensions. Returns a :class:`~jinja2.lexer.TokenStream`.
"""
source = self.preprocess(source, name, filename)
stream = self.lexer.tokenize(source, name, filename, state)
5 years ago
for ext in self.iter_extensions():
stream = ext.filter_stream(stream) # type: ignore
5 years ago
if not isinstance(stream, TokenStream):
stream = TokenStream(stream, name, filename) # type: ignore
5 years ago
return stream
def _generate(
self,
source: nodes.Template,
name: t.Optional[str],
filename: t.Optional[str],
defer_init: bool = False,
) -> str:
5 years ago
"""Internal hook that can be overridden to hook a different generate
method in.
.. versionadded:: 2.5
"""
return generate( # type: ignore
source,
self,
name,
filename,
defer_init=defer_init,
optimized=self.optimized,
)
def _compile(self, source: str, filename: str) -> CodeType:
5 years ago
"""Internal hook that can be overridden to hook a different compile
method in.
.. versionadded:: 2.5
"""
return compile(source, filename, "exec") # type: ignore
@typing.overload
def compile( # type: ignore
self,
source: t.Union[str, nodes.Template],
name: t.Optional[str] = None,
filename: t.Optional[str] = None,
raw: "te.Literal[False]" = False,
defer_init: bool = False,
) -> CodeType:
...
@typing.overload
def compile(
self,
source: t.Union[str, nodes.Template],
name: t.Optional[str] = None,
filename: t.Optional[str] = None,
raw: "te.Literal[True]" = ...,
defer_init: bool = False,
) -> str:
...
5 years ago
@internalcode
def compile(
self,
source: t.Union[str, nodes.Template],
name: t.Optional[str] = None,
filename: t.Optional[str] = None,
raw: bool = False,
defer_init: bool = False,
) -> t.Union[str, CodeType]:
5 years ago
"""Compile a node or template source code. The `name` parameter is
the load name of the template after it was joined using
:meth:`join_path` if necessary, not the filename on the file system.
the `filename` parameter is the estimated filename of the template on
the file system. If the template came from a database or memory this
can be omitted.
The return value of this method is a python code object. If the `raw`
parameter is `True` the return value will be a string with python
code equivalent to the bytecode returned otherwise. This method is
mainly used internally.
`defer_init` is use internally to aid the module code generator. This
causes the generated code to be able to import without the global
environment variable to be set.
.. versionadded:: 2.4
`defer_init` parameter added.
"""
source_hint = None
try:
if isinstance(source, str):
5 years ago
source_hint = source
source = self._parse(source, name, filename)
source = self._generate(source, name, filename, defer_init=defer_init)
5 years ago
if raw:
return source
if filename is None:
filename = "<template>"
5 years ago
return self._compile(source, filename)
except TemplateSyntaxError:
self.handle_exception(source=source_hint)
5 years ago
def compile_expression(
self, source: str, undefined_to_none: bool = True
) -> "TemplateExpression":
5 years ago
"""A handy helper method that returns a callable that accepts keyword
arguments that appear as variables in the expression. If called it
returns the result of the expression.
This is useful if applications want to use the same rules as Jinja
in template "configuration files" or similar situations.
Example usage:
>>> env = Environment()
>>> expr = env.compile_expression('foo == 42')
>>> expr(foo=23)
False
>>> expr(foo=42)
True
Per default the return value is converted to `None` if the
expression returns an undefined value. This can be changed
by setting `undefined_to_none` to `False`.
>>> env.compile_expression('var')() is None
True
>>> env.compile_expression('var', undefined_to_none=False)()
Undefined
.. versionadded:: 2.1
"""
parser = Parser(self, source, state="variable")
5 years ago
try:
expr = parser.parse_expression()
if not parser.stream.eos:
raise TemplateSyntaxError(
"chunk after expression", parser.stream.current.lineno, None, None
)
5 years ago
expr.set_environment(self)
except TemplateSyntaxError:
self.handle_exception(source=source)
body = [nodes.Assign(nodes.Name("result", "store"), expr, lineno=1)]
5 years ago
template = self.from_string(nodes.Template(body, lineno=1))
return TemplateExpression(template, undefined_to_none)
def compile_templates(
self,
target: t.Union[str, os.PathLike],
extensions: t.Optional[t.Collection[str]] = None,
filter_func: t.Optional[t.Callable[[str], bool]] = None,
zip: t.Optional[str] = "deflated",
log_function: t.Optional[t.Callable[[str], None]] = None,
ignore_errors: bool = True,
) -> None:
5 years ago
"""Finds all the templates the loader can find, compiles them
and stores them in `target`. If `zip` is `None`, instead of in a
zipfile, the templates will be stored in a directory.
By default a deflate zip algorithm is used. To switch to
the stored algorithm, `zip` can be set to ``'stored'``.
`extensions` and `filter_func` are passed to :meth:`list_templates`.
Each template returned will be compiled to the target folder or
zipfile.
By default template compilation errors are ignored. In case a
log function is provided, errors are logged. If you want template
syntax errors to abort the compilation you can set `ignore_errors`
to `False` and you will get an exception on syntax errors.
.. versionadded:: 2.4
"""
from .loaders import ModuleLoader
5 years ago
if log_function is None:
def log_function(x: str) -> None:
pass
5 years ago
assert log_function is not None
assert self.loader is not None, "No loader configured."
5 years ago
def write_file(filename: str, data: str) -> None:
5 years ago
if zip:
info = ZipInfo(filename)
info.external_attr = 0o755 << 16
zip_file.writestr(info, data)
else:
with open(os.path.join(target, filename), "wb") as f:
f.write(data.encode("utf8"))
5 years ago
if zip is not None:
from zipfile import ZipFile, ZipInfo, ZIP_DEFLATED, ZIP_STORED
zip_file = ZipFile(
target, "w", dict(deflated=ZIP_DEFLATED, stored=ZIP_STORED)[zip]
)
log_function(f"Compiling into Zip archive {target!r}")
5 years ago
else:
if not os.path.isdir(target):
os.makedirs(target)
log_function(f"Compiling into folder {target!r}")
5 years ago
try:
for name in self.list_templates(extensions, filter_func):
source, filename, _ = self.loader.get_source(self, name)
try:
code = self.compile(source, name, filename, True, True)
except TemplateSyntaxError as e:
if not ignore_errors:
raise
log_function(f'Could not compile "{name}": {e}')
5 years ago
continue
filename = ModuleLoader.get_module_filename(name)
write_file(filename, code)
log_function(f'Compiled "{name}" as {filename}')
5 years ago
finally:
if zip:
zip_file.close()
log_function("Finished compiling templates")
5 years ago
def list_templates(
self,
extensions: t.Optional[t.Collection[str]] = None,
filter_func: t.Optional[t.Callable[[str], bool]] = None,
) -> t.List[str]:
5 years ago
"""Returns a list of templates for this environment. This requires
that the loader supports the loader's
:meth:`~BaseLoader.list_templates` method.
If there are other files in the template folder besides the
actual templates, the returned list can be filtered. There are two
ways: either `extensions` is set to a list of file extensions for
templates, or a `filter_func` can be provided which is a callable that
is passed a template name and should return `True` if it should end up
in the result list.
If the loader does not support that, a :exc:`TypeError` is raised.
.. versionadded:: 2.4
"""
assert self.loader is not None, "No loader configured."
names = self.loader.list_templates()
5 years ago
if extensions is not None:
if filter_func is not None:
raise TypeError(
"either extensions or filter_func can be passed, but not both"
)
def filter_func(x: str) -> bool:
return "." in x and x.rsplit(".", 1)[1] in extensions # type: ignore
5 years ago
if filter_func is not None:
names = [name for name in names if filter_func(name)]
5 years ago
return names
def handle_exception(self, source: t.Optional[str] = None) -> "te.NoReturn":
5 years ago
"""Exception handling helper. This is used internally to either raise
rewritten exceptions or return a rendered traceback for the template.
"""
from .debug import rewrite_traceback_stack
raise rewrite_traceback_stack(source=source)
def join_path(self, template: str, parent: str) -> str:
5 years ago
"""Join a template with the parent. By default all the lookups are
relative to the loader root so this method returns the `template`
parameter unchanged, but if the paths should be relative to the
parent template, this function can be used to calculate the real
template name.
Subclasses may override this method and implement template path
joining here.
"""
return template
@internalcode
def _load_template(
self, name: str, globals: t.Optional[t.Mapping[str, t.Any]]
) -> "Template":
5 years ago
if self.loader is None:
raise TypeError("no loader for this environment specified")
5 years ago
cache_key = (weakref.ref(self.loader), name)
if self.cache is not None:
template = self.cache.get(cache_key)
if template is not None and (
not self.auto_reload or template.is_up_to_date
):
# template.globals is a ChainMap, modifying it will only
# affect the template, not the environment globals.
if globals:
template.globals.update(globals)
5 years ago
return template
template = self.loader.load(self, name, self.make_globals(globals))
5 years ago
if self.cache is not None:
self.cache[cache_key] = template
return template
@internalcode
def get_template(
self,
name: t.Union[str, "Template"],
parent: t.Optional[str] = None,
globals: t.Optional[t.Mapping[str, t.Any]] = None,
) -> "Template":
"""Load a template by name with :attr:`loader` and return a
:class:`Template`. If the template does not exist a
:exc:`TemplateNotFound` exception is raised.
:param name: Name of the template to load.
:param parent: The name of the parent template importing this
template. :meth:`join_path` can be used to implement name
transformations with this.
:param globals: Extend the environment :attr:`globals` with
these extra variables available for all renders of this
template. If the template has already been loaded and
cached, its globals are updated with any new items.
.. versionchanged:: 3.0
If a template is loaded from cache, ``globals`` will update
the template's globals instead of ignoring the new values.
5 years ago
.. versionchanged:: 2.4
If ``name`` is a :class:`Template` object it is returned
unchanged.
5 years ago
"""
if isinstance(name, Template):
return name
if parent is not None:
name = self.join_path(name, parent)
return self._load_template(name, globals)
5 years ago
@internalcode
def select_template(
self,
names: t.Iterable[t.Union[str, "Template"]],
parent: t.Optional[str] = None,
globals: t.Optional[t.Mapping[str, t.Any]] = None,
) -> "Template":
"""Like :meth:`get_template`, but tries loading multiple names.
If none of the names can be loaded a :exc:`TemplatesNotFound`
exception is raised.
:param names: List of template names to try loading in order.
:param parent: The name of the parent template importing this
template. :meth:`join_path` can be used to implement name
transformations with this.
:param globals: Extend the environment :attr:`globals` with
these extra variables available for all renders of this
template. If the template has already been loaded and
cached, its globals are updated with any new items.
.. versionchanged:: 3.0
If a template is loaded from cache, ``globals`` will update
the template's globals instead of ignoring the new values.
.. versionchanged:: 2.11
If ``names`` is :class:`Undefined`, an :exc:`UndefinedError`
is raised instead. If no templates were found and ``names``
contains :class:`Undefined`, the message is more helpful.
5 years ago
.. versionchanged:: 2.4
If ``names`` contains a :class:`Template` object it is
returned unchanged.
.. versionadded:: 2.3
5 years ago
"""
if isinstance(names, Undefined):
names._fail_with_undefined_error()
5 years ago
if not names:
raise TemplatesNotFound(
message="Tried to select from an empty list of templates."
)
5 years ago
for name in names:
if isinstance(name, Template):
return name
if parent is not None:
name = self.join_path(name, parent)
try:
return self._load_template(name, globals)
except (TemplateNotFound, UndefinedError):
5 years ago
pass
raise TemplatesNotFound(names) # type: ignore
5 years ago
@internalcode
def get_or_select_template(
self,
template_name_or_list: t.Union[
str, "Template", t.List[t.Union[str, "Template"]]
],
parent: t.Optional[str] = None,
globals: t.Optional[t.Mapping[str, t.Any]] = None,
) -> "Template":
"""Use :meth:`select_template` if an iterable of template names
is given, or :meth:`get_template` if one name is given.
5 years ago
.. versionadded:: 2.3
"""
if isinstance(template_name_or_list, (str, Undefined)):
5 years ago
return self.get_template(template_name_or_list, parent, globals)
elif isinstance(template_name_or_list, Template):
return template_name_or_list
return self.select_template(template_name_or_list, parent, globals)
def from_string(
self,
source: t.Union[str, nodes.Template],
globals: t.Optional[t.Mapping[str, t.Any]] = None,
template_class: t.Optional[t.Type["Template"]] = None,
) -> "Template":
"""Load a template from a source string without using
:attr:`loader`.
:param source: Jinja source to compile into a template.
:param globals: Extend the environment :attr:`globals` with
these extra variables available for all renders of this
template. If the template has already been loaded and
cached, its globals are updated with any new items.
:param template_class: Return an instance of this
:class:`Template` class.
5 years ago
"""
gs = self.make_globals(globals)
5 years ago
cls = template_class or self.template_class
return cls.from_code(self, self.compile(source), gs, None)
def make_globals(
self, d: t.Optional[t.Mapping[str, t.Any]]
) -> t.MutableMapping[str, t.Any]:
"""Make the globals map for a template. Any given template
globals overlay the environment :attr:`globals`.
Returns a :class:`collections.ChainMap`. This allows any changes
to a template's globals to only affect that template, while
changes to the environment's globals are still reflected.
However, avoid modifying any globals after a template is loaded.
:param d: Dict of template-specific globals.
.. versionchanged:: 3.0
Use :class:`collections.ChainMap` to always prevent mutating
environment globals.
"""
if d is None:
d = {}
return ChainMap(d, self.globals)
class Template:
"""A compiled template that can be rendered.
Use the methods on :class:`Environment` to create or load templates.
The environment is used to configure how templates are compiled and
behave.
It is also possible to create a template object directly. This is
not usually recommended. The constructor takes most of the same
arguments as :class:`Environment`. All templates created with the
same environment arguments share the same ephemeral ``Environment``
instance behind the scenes.
A template object should be considered immutable. Modifications on
the object are not supported.
5 years ago
"""
#: Type of environment to create when creating a template directly
#: rather than through an existing environment.
environment_class: t.Type[Environment] = Environment
environment: Environment
globals: t.MutableMapping[str, t.Any]
name: t.Optional[str]
filename: t.Optional[str]
blocks: t.Dict[str, t.Callable[[Context], t.Iterator[str]]]
root_render_func: t.Callable[[Context], t.Iterator[str]]
_module: t.Optional["TemplateModule"]
_debug_info: str
_uptodate: t.Optional[t.Callable[[], bool]]
def __new__(
cls,
source: t.Union[str, nodes.Template],
block_start_string: str = BLOCK_START_STRING,
block_end_string: str = BLOCK_END_STRING,
variable_start_string: str = VARIABLE_START_STRING,
variable_end_string: str = VARIABLE_END_STRING,
comment_start_string: str = COMMENT_START_STRING,
comment_end_string: str = COMMENT_END_STRING,
line_statement_prefix: t.Optional[str] = LINE_STATEMENT_PREFIX,
line_comment_prefix: t.Optional[str] = LINE_COMMENT_PREFIX,
trim_blocks: bool = TRIM_BLOCKS,
lstrip_blocks: bool = LSTRIP_BLOCKS,
newline_sequence: "te.Literal['\\n', '\\r\\n', '\\r']" = NEWLINE_SEQUENCE,
keep_trailing_newline: bool = KEEP_TRAILING_NEWLINE,
extensions: t.Sequence[t.Union[str, t.Type["Extension"]]] = (),
optimized: bool = True,
undefined: t.Type[Undefined] = Undefined,
finalize: t.Optional[t.Callable[..., t.Any]] = None,
autoescape: t.Union[bool, t.Callable[[t.Optional[str]], bool]] = False,
enable_async: bool = False,
) -> t.Any: # it returns a `Template`, but this breaks the sphinx build...
5 years ago
env = get_spontaneous_environment(
cls.environment_class, # type: ignore
block_start_string,
block_end_string,
variable_start_string,
variable_end_string,
comment_start_string,
comment_end_string,
line_statement_prefix,
line_comment_prefix,
trim_blocks,
lstrip_blocks,
newline_sequence,
keep_trailing_newline,
frozenset(extensions),
optimized,
undefined, # type: ignore
finalize,
autoescape,
None,
0,
False,
None,
enable_async,
)
5 years ago
return env.from_string(source, template_class=cls)
@classmethod
def from_code(
cls,
environment: Environment,
code: CodeType,
globals: t.MutableMapping[str, t.Any],
uptodate: t.Optional[t.Callable[[], bool]] = None,
) -> "Template":
5 years ago
"""Creates a template object from compiled code and the globals. This
is used by the loaders and environment to create a template object.
"""
namespace = {"environment": environment, "__file__": code.co_filename}
5 years ago
exec(code, namespace)
rv = cls._from_namespace(environment, namespace, globals)
rv._uptodate = uptodate
return rv
@classmethod
def from_module_dict(
cls,
environment: Environment,
module_dict: t.MutableMapping[str, t.Any],
globals: t.MutableMapping[str, t.Any],
) -> "Template":
5 years ago
"""Creates a template object from a module. This is used by the
module loader to create a template object.
.. versionadded:: 2.4
"""
return cls._from_namespace(environment, module_dict, globals)
@classmethod
def _from_namespace(
cls,
environment: Environment,
namespace: t.MutableMapping[str, t.Any],
globals: t.MutableMapping[str, t.Any],
) -> "Template":
t: "Template" = object.__new__(cls)
5 years ago
t.environment = environment
t.globals = globals
t.name = namespace["name"]
t.filename = namespace["__file__"]
t.blocks = namespace["blocks"]
5 years ago
# render function and module
t.root_render_func = namespace["root"] # type: ignore
5 years ago
t._module = None
# debug and loader helpers
t._debug_info = namespace["debug_info"]
5 years ago
t._uptodate = None
# store the reference
namespace["environment"] = environment
namespace["__jinja_template__"] = t
5 years ago
return t
def render(self, *args: t.Any, **kwargs: t.Any) -> str:
5 years ago
"""This method accepts the same arguments as the `dict` constructor:
A dict, a dict subclass or some keyword arguments. If no arguments
are given the context will be empty. These two calls do the same::
template.render(knights='that say nih')
template.render({'knights': 'that say nih'})
This will return the rendered template as a string.
5 years ago
"""
if self.environment.is_async:
import asyncio
close = False
if sys.version_info < (3, 7):
loop = asyncio.get_event_loop()
else:
try:
loop = asyncio.get_running_loop()
except RuntimeError:
loop = asyncio.new_event_loop()
close = True
try:
return loop.run_until_complete(self.render_async(*args, **kwargs))
finally:
if close:
loop.close()
ctx = self.new_context(dict(*args, **kwargs))
5 years ago
try:
return concat(self.root_render_func(ctx)) # type: ignore
5 years ago
except Exception:
self.environment.handle_exception()
5 years ago
async def render_async(self, *args: t.Any, **kwargs: t.Any) -> str:
5 years ago
"""This works similar to :meth:`render` but returns a coroutine
that when awaited returns the entire rendered template string. This
requires the async feature to be enabled.
Example usage::
await template.render_async(knights='that say nih; asynchronously')
"""
if not self.environment.is_async:
raise RuntimeError(
"The environment was not created with async mode enabled."
)
ctx = self.new_context(dict(*args, **kwargs))
5 years ago
try:
return concat([n async for n in self.root_render_func(ctx)]) # type: ignore
except Exception:
return self.environment.handle_exception()
def stream(self, *args: t.Any, **kwargs: t.Any) -> "TemplateStream":
5 years ago
"""Works exactly like :meth:`generate` but returns a
:class:`TemplateStream`.
"""
return TemplateStream(self.generate(*args, **kwargs))
def generate(self, *args: t.Any, **kwargs: t.Any) -> t.Iterator[str]:
5 years ago
"""For very large templates it can be useful to not render the whole
template at once but evaluate each statement after another and yield
piece for piece. This method basically does exactly that and returns
a generator that yields one item after another as strings.
5 years ago
It accepts the same arguments as :meth:`render`.
"""
if self.environment.is_async:
import asyncio
async def to_list() -> t.List[str]:
return [x async for x in self.generate_async(*args, **kwargs)]
if sys.version_info < (3, 7):
loop = asyncio.get_event_loop()
out = loop.run_until_complete(to_list())
else:
out = asyncio.run(to_list())
yield from out
return
ctx = self.new_context(dict(*args, **kwargs))
5 years ago
try:
yield from self.root_render_func(ctx) # type: ignore
5 years ago
except Exception:
yield self.environment.handle_exception()
5 years ago
async def generate_async(
self, *args: t.Any, **kwargs: t.Any
) -> t.AsyncIterator[str]:
5 years ago
"""An async version of :meth:`generate`. Works very similarly but
returns an async iterator instead.
"""
if not self.environment.is_async:
raise RuntimeError(
"The environment was not created with async mode enabled."
)
ctx = self.new_context(dict(*args, **kwargs))
5 years ago
try:
async for event in self.root_render_func(ctx): # type: ignore
yield event
except Exception:
yield self.environment.handle_exception()
def new_context(
self,
vars: t.Optional[t.Dict[str, t.Any]] = None,
shared: bool = False,
locals: t.Optional[t.Mapping[str, t.Any]] = None,
) -> Context:
5 years ago
"""Create a new :class:`Context` for this template. The vars
provided will be passed to the template. Per default the globals
are added to the context. If shared is set to `True` the data
is passed as is to the context without adding the globals.
5 years ago
`locals` can be a dict of local variables for internal usage.
"""
return new_context(
self.environment, self.name, self.blocks, vars, shared, self.globals, locals
)
def make_module(
self,
vars: t.Optional[t.Dict[str, t.Any]] = None,
shared: bool = False,
locals: t.Optional[t.Mapping[str, t.Any]] = None,
) -> "TemplateModule":
5 years ago
"""This method works like the :attr:`module` attribute when called
without arguments but it will evaluate the template on every call
rather than caching it. It's also possible to provide
a dict which is then used as context. The arguments are the same
as for the :meth:`new_context` method.
"""
ctx = self.new_context(vars, shared, locals)
return TemplateModule(self, ctx)
async def make_module_async(
self,
vars: t.Optional[t.Dict[str, t.Any]] = None,
shared: bool = False,
locals: t.Optional[t.Mapping[str, t.Any]] = None,
) -> "TemplateModule":
5 years ago
"""As template module creation can invoke template code for
asynchronous executions this method must be used instead of the
5 years ago
normal :meth:`make_module` one. Likewise the module attribute
becomes unavailable in async mode.
"""
ctx = self.new_context(vars, shared, locals)
return TemplateModule(
self, ctx, [x async for x in self.root_render_func(ctx)] # type: ignore
)
5 years ago
@internalcode
def _get_default_module(self, ctx: t.Optional[Context] = None) -> "TemplateModule":
"""If a context is passed in, this means that the template was
imported. Imported templates have access to the current
template's globals by default, but they can only be accessed via
the context during runtime.
If there are new globals, we need to create a new module because
the cached module is already rendered and will not have access
to globals from the current context. This new module is not
cached because the template can be imported elsewhere, and it
should have access to only the current template's globals.
"""
if self.environment.is_async:
raise RuntimeError("Module is not available in async mode.")
if ctx is not None:
keys = ctx.globals_keys - self.globals.keys()
if keys:
return self.make_module({k: ctx.parent[k] for k in keys})
if self._module is None:
self._module = self.make_module()
return self._module
async def _get_default_module_async(
self, ctx: t.Optional[Context] = None
) -> "TemplateModule":
if ctx is not None:
keys = ctx.globals_keys - self.globals.keys()
if keys:
return await self.make_module_async({k: ctx.parent[k] for k in keys})
if self._module is None:
self._module = await self.make_module_async()
return self._module
5 years ago
@property
def module(self) -> "TemplateModule":
5 years ago
"""The template as module. This is used for imports in the
template runtime but is also useful if one wants to access
exported template variables from the Python layer:
>>> t = Template('{% macro foo() %}42{% endmacro %}23')
>>> str(t.module)
'23'
>>> t.module.foo() == u'42'
True
This attribute is not available if async mode is enabled.
"""
return self._get_default_module()
def get_corresponding_lineno(self, lineno: int) -> int:
5 years ago
"""Return the source line number of a line number in the
generated bytecode as they are not in sync.
"""
for template_line, code_line in reversed(self.debug_info):
if code_line <= lineno:
return template_line
return 1
@property
def is_up_to_date(self) -> bool:
5 years ago
"""If this variable is `False` there is a newer version available."""
if self._uptodate is None:
return True
return self._uptodate()
@property
def debug_info(self) -> t.List[t.Tuple[int, int]]:
5 years ago
"""The debug info mapping."""
if self._debug_info:
return [
tuple(map(int, x.split("="))) # type: ignore
for x in self._debug_info.split("&")
]
return []
5 years ago
def __repr__(self) -> str:
5 years ago
if self.name is None:
name = f"memory:{id(self):x}"
5 years ago
else:
name = repr(self.name)
return f"<{type(self).__name__} {name}>"
5 years ago
class TemplateModule:
5 years ago
"""Represents an imported template. All the exported names of the
template are available as attributes on this object. Additionally
converting it into a string renders the contents.
5 years ago
"""
def __init__(
self,
template: Template,
context: Context,
body_stream: t.Optional[t.Iterable[str]] = None,
) -> None:
5 years ago
if body_stream is None:
if context.environment.is_async:
raise RuntimeError(
"Async mode requires a body stream to be passed to"
" a template module. Use the async methods of the"
" API you are using."
)
body_stream = list(template.root_render_func(context)) # type: ignore
5 years ago
self._body_stream = body_stream
self.__dict__.update(context.get_exported())
self.__name__ = template.name
def __html__(self) -> Markup:
5 years ago
return Markup(concat(self._body_stream))
def __str__(self) -> str:
5 years ago
return concat(self._body_stream)
def __repr__(self) -> str:
5 years ago
if self.__name__ is None:
name = f"memory:{id(self):x}"
5 years ago
else:
name = repr(self.__name__)
return f"<{type(self).__name__} {name}>"
5 years ago
class TemplateExpression:
5 years ago
"""The :meth:`jinja2.Environment.compile_expression` method returns an
instance of this object. It encapsulates the expression-like access
to the template with an expression it wraps.
"""
def __init__(self, template: Template, undefined_to_none: bool) -> None:
5 years ago
self._template = template
self._undefined_to_none = undefined_to_none
def __call__(self, *args: t.Any, **kwargs: t.Any) -> t.Optional[t.Any]:
5 years ago
context = self._template.new_context(dict(*args, **kwargs))
consume(self._template.root_render_func(context)) # type: ignore
rv = context.vars["result"]
5 years ago
if self._undefined_to_none and isinstance(rv, Undefined):
rv = None
return rv
class TemplateStream:
5 years ago
"""A template stream works pretty much like an ordinary python generator
but it can buffer multiple items to reduce the number of total iterations.
Per default the output is unbuffered which means that for every unbuffered
instruction in the template one string is yielded.
5 years ago
If buffering is enabled with a buffer size of 5, five items are combined
into a new string. This is mainly useful if you are streaming
5 years ago
big templates to a client via WSGI which flushes after each iteration.
"""
def __init__(self, gen: t.Iterator[str]) -> None:
5 years ago
self._gen = gen
self.disable_buffering()
def dump(
self,
fp: t.Union[str, t.IO],
encoding: t.Optional[str] = None,
errors: t.Optional[str] = "strict",
) -> None:
5 years ago
"""Dump the complete stream into a file or file-like object.
Per default strings are written, if you want to encode
5 years ago
before writing specify an `encoding`.
Example usage::
Template('Hello {{ name }}!').stream(name='foo').dump('hello.html')
"""
close = False
if isinstance(fp, str):
5 years ago
if encoding is None:
encoding = "utf-8"
fp = open(fp, "wb")
5 years ago
close = True
try:
if encoding is not None:
iterable = (x.encode(encoding, errors) for x in self) # type: ignore
5 years ago
else:
iterable = self # type: ignore
if hasattr(fp, "writelines"):
5 years ago
fp.writelines(iterable)
else:
for item in iterable:
fp.write(item)
finally:
if close:
fp.close()
def disable_buffering(self) -> None:
5 years ago
"""Disable the output buffering."""
self._next = partial(next, self._gen)
self.buffered = False
def _buffered_generator(self, size: int) -> t.Iterator[str]:
buf: t.List[str] = []
5 years ago
c_size = 0
push = buf.append
while True:
5 years ago
try:
while c_size < size:
c = next(self._gen)
push(c)
if c:
c_size += 1
except StopIteration:
if not c_size:
return
yield concat(buf)
del buf[:]
c_size = 0
def enable_buffering(self, size: int = 5) -> None:
5 years ago
"""Enable buffering. Buffer `size` items before yielding them."""
if size <= 1:
raise ValueError("buffer size too small")
5 years ago
self.buffered = True
self._next = partial(next, self._buffered_generator(size))
def __iter__(self) -> "TemplateStream":
5 years ago
return self
def __next__(self) -> str:
return self._next() # type: ignore
5 years ago
# hook in default template class. if anyone reads this comment: ignore that
# it's possible to use custom templates ;-)
Environment.template_class = Template