diff options
Diffstat (limited to 'Lib/email/policy.py')
| -rw-r--r-- | Lib/email/policy.py | 172 |
1 files changed, 5 insertions, 167 deletions
diff --git a/Lib/email/policy.py b/Lib/email/policy.py index 585a752..dae2dc7 100644 --- a/Lib/email/policy.py +++ b/Lib/email/policy.py @@ -1,174 +1,12 @@ -"""Policy framework for the email package. - -Allows fine grained feature control of how the package parses and emits data. +"""This will be the home for the policy that hooks in the new +code that adds all the email6 features. """ -__all__ = [ - 'Policy', - 'default', - 'strict', - 'SMTP', - 'HTTP', - ] - - -class _PolicyBase: - - """Policy Object basic framework. - - This class is useless unless subclassed. A subclass should define - class attributes with defaults for any values that are to be - managed by the Policy object. The constructor will then allow - non-default values to be set for these attributes at instance - creation time. The instance will be callable, taking these same - attributes keyword arguments, and returning a new instance - identical to the called instance except for those values changed - by the keyword arguments. Instances may be added, yielding new - instances with any non-default values from the right hand - operand overriding those in the left hand operand. That is, - - A + B == A(<non-default values of B>) - - The repr of an instance can be used to reconstruct the object - if and only if the repr of the values can be used to reconstruct - those values. - - """ - - def __init__(self, **kw): - """Create new Policy, possibly overriding some defaults. - - See class docstring for a list of overridable attributes. - - """ - for name, value in kw.items(): - if hasattr(self, name): - super(_PolicyBase,self).__setattr__(name, value) - else: - raise TypeError( - "{!r} is an invalid keyword argument for {}".format( - name, self.__class__.__name__)) - - def __repr__(self): - args = [ "{}={!r}".format(name, value) - for name, value in self.__dict__.items() ] - return "{}({})".format(self.__class__.__name__, ', '.join(args)) - - def clone(self, **kw): - """Return a new instance with specified attributes changed. - - The new instance has the same attribute values as the current object, - except for the changes passed in as keyword arguments. - - """ - for attr, value in self.__dict__.items(): - if attr not in kw: - kw[attr] = value - return self.__class__(**kw) - - def __setattr__(self, name, value): - if hasattr(self, name): - msg = "{!r} object attribute {!r} is read-only" - else: - msg = "{!r} object has no attribute {!r}" - raise AttributeError(msg.format(self.__class__.__name__, name)) - - def __add__(self, other): - """Non-default values from right operand override those from left. - - The object returned is a new instance of the subclass. - - """ - return self.clone(**other.__dict__) - - -class Policy(_PolicyBase): - - """Controls for how messages are interpreted and formatted. - - Most of the classes and many of the methods in the email package - accept Policy objects as parameters. A Policy object contains a set - of values and functions that control how input is interpreted and how - output is rendered. For example, the parameter 'raise_on_defect' - controls whether or not an RFC violation throws an error or not, - while 'max_line_length' controls the maximum length of output lines - when a Message is serialized. - - Any valid attribute may be overridden when a Policy is created by - passing it as a keyword argument to the constructor. Policy - objects are immutable, but a new Policy object can be created - with only certain values changed by calling the Policy instance - with keyword arguments. Policy objects can also be added, - producing a new Policy object in which the non-default attributes - set in the right hand operand overwrite those specified in the - left operand. - - Settable attributes: - - raise_on_defect -- If true, then defects should be raised - as errors. Default False. - - linesep -- string containing the value to use as - separation between output lines. Default '\n'. - - must_be_7bit -- output must contain only 7bit clean data. - Default False. - - max_line_length -- maximum length of lines, excluding 'linesep', - during serialization. None means no line - wrapping is done. Default is 78. - - Methods: - - register_defect(obj, defect) - defect is a Defect instance. The default implementation appends defect - to the objs 'defects' attribute. - - handle_defect(obj, defect) - intended to be called by parser code that finds a defect. If - raise_on_defect is True, defect is raised as an error, otherwise - register_defect is called. - - """ - - raise_on_defect = False - linesep = '\n' - must_be_7bit = False - max_line_length = 78 - - def handle_defect(self, obj, defect): - """Based on policy, either raise defect or call register_defect. - - handle_defect(obj, defect) - - defect should be a Defect subclass, but in any case must be an - Exception subclass. obj is the object on which the defect should be - registered if it is not raised. If the raise_on_defect is True, the - defect is raised as an error, otherwise the object and the defect are - passed to register_defect. - - This class is intended to be called by parsers that discover defects, - and will not be called from code using the library unless that code is - implementing an alternate parser. - - """ - if self.raise_on_defect: - raise defect - self.register_defect(obj, defect) - - def register_defect(self, obj, defect): - """Record 'defect' on 'obj'. - - Called by handle_defect if raise_on_defect is False. This method is - part of the Policy API so that Policy subclasses can implement custom - defect handling. The default implementation calls the append method - of the defects attribute of obj. - - """ - obj.defects.append(defect) +from email._policybase import Policy, compat32, Compat32 +# XXX: temporarily derive everything from compat32. -default = Policy() +default = compat32 strict = default.clone(raise_on_defect=True) SMTP = default.clone(linesep='\r\n') HTTP = default.clone(linesep='\r\n', max_line_length=None) |