========= Reference ========= *************************** :mod:`classytags.arguments` *************************** .. module:: classytags.arguments This module contains standard argument types. .. class:: Argument(name[, default=None][, required=True], [resolve=True]) A basic single value argument with *name* as it's name. *default* is used if *required* is False and this argument is not given. If *resolve* is ``False``, the argument will not try to resolve it's contents against the context. This is especially useful for 'as varname' arguments. Note that quotation marks around the argument will be removed if there are any. .. attribute:: value_class The class to be used to wrap the value in. Defaults to :class:`classytags.values.StringValue.` .. method:: get_default() Returns the default value for this argument .. method:: parse(parser, token, tagname, kwargs) Parses a single *token* into *kwargs*. Should return ``True`` if it consumed this token or ``False`` if it didn't. .. method:: parse_token(parser, token) Parses a single *token* using *parser* into an object which is can be resolved against a context. Usually this is a template variable, a filter expression or a :class:`classytags.utils.TemplateConstant`. .. class:: KeywordArgument(name[, default=None][, required=True] \ [, resolve=True][, defaultkey=None][, splitter='=']) An argument that allows ``key=value`` notation. *defaultkey* is used as key if no key is given or the default value should be used. *splitter* is used to split the key value pair. .. attribute:: wrapper_class Class to use to wrap the key value pair in. Defaults to :class:`classytags.values.DictValue`. .. class:: IntegerArgument Same as :class:`classytags.arguments.Argument` but with :class:`classytags.values.IntegerValue` as :attr:`value_class`. .. class:: ChoiceArgument(name, choices[, default=None][, required=True] \ [, resolve=True]) An argument which validates it's input against predefined choices. .. class:: MultiValueArgument(name[, default=NULL][, required=True] \ [, max_values=None][, resolve=True]) An argument which accepts a variable amount of values. The maximum amount of accepted values can be controlled with the *max_values* argument which defaults to ``None``, meaning there is no maximum amount of values. *default* is an empty list if *required* is ``False``. *resolve* has the same effects as in :class:`classytags.arguments.Argument` however applies to all values of this argument. The default value for :attr:`value_class` is$ :class:`classytags.values.ListValue`. .. attribute:: sequence_class Class to be used to build the sequence. Defaults to :class:`classytags.utils.ResolvableList`. .. class:: MultiKeywordArgument(name[, default=None][, required=True] \ [, resolve=True][, max_values=None] \ [, splitter='=']) Similar to :class:`classytags.arguments.KeywordArgument` but allows multiple key value pairs to be given. The will be merged into one dictionary. Arguments are the same as for :class:`classytags.arguments.KeywordArgument` and :class:`classytags.arguments.MultiValueArgument`, except that *default_key* is not accepted and *default* should be a dictionary or ``None``. .. class:: Flag(name[, default=NULL][, true_values=None][, false_values=None] \ [, case_sensitive=False]) A boolean flag. Either *true_values* or *false_values* must be provided. If *default* is not given, this argument is required. *true_values* and *false_values* must be either a list or a tuple of strings. If both *true_values* and *false_values* are given, any value not in those sequences will raise a :class:`classytag.exceptions.InvalidFlag` exception. *case_sensitive* defaults to ``False`` and controls whether the values are matched case sensitive or not. ************************ :mod:`classytags.blocks` ************************ .. module:: classytags.blocks This module contains classes for :ref:`advanced-block-definition`. .. class:: BlockDefintion(alias, *names) A block definition with the given alias and a sequence of names. The members of the names sequence must either be strings, :class:`classytags.blocks.VariableBlockName` instances or other objects implementing at least a :meth:`collect` method compatible with the one of :class:`classytags.blocks.VariableBlockName`. .. attribute:: alias The alias for this definition to be used in the tag's kwargs. .. attribute:: names Sequence of strings or block name definitions. .. method:: validate(options) Validates this definition against an instance of :class:`classytags.core.Options` by calling the :meth:`validate` on all it's :attr:`names` if such a method is available. .. method:: collect(parser) Returns a sequence of strings to be used in the ``parse_until`` statement. This is a sequence of strings that this block accepts to be handled. The parser argument is an instance of :class:`classytags.parser.Parser`. .. class:: VariableBlockName(template, argname) A block name definition to be used in :class:`classytags.blocks.BlockDefinition` to implement block names that depend on the (unresolved) value of an argument. The template argument to this class should be a string with the ``value`` string substitution placeholder. For example: ``'end_my_block %(value)s'``. The argname argument is the name of the argument from which the value should be extracted. .. method:: validate(options) Validates that the given argname is actually available on the tag. .. method:: collect(parser) Returns the template substitued with the value extracted from the tag. ********************** :mod:`classytags.core` ********************** .. module:: classytags.core This module contains the core objects to create tags. .. class:: Options(*options, **kwargs) Holds the options of a tag. *options* should be a sequence of :class:`classytags.arguments.Argument` subclasses or strings (for breakpoints). You can give they keyword argument *blocks* to define a list of blocks to parse until. You can specify a custom argument parser by providing the keyword argument *parser_class*. .. attribute:: all_argument_names A list of all argument names in this tag options. Used by :class:`classytags.blocks.VariableBlockName` to validate it's definition. .. method:: get_parser_class() Returns :class:`classytags.parser.Parser` or a subclass of it. .. method:: bootstrap() An internal method to bootstrap the arguments. Returns an instance of :class:`classytags.utils.StructuredOptions`. .. method:: parse(parser, token): An internal method to parse the template tag. Returns a tuple ``(arguments, blocks)``. .. class:: TagMeta The metaclass of :class:`classytags.core.Tag` which ensures the tag has a name attribute by setting one based on the classes name if none is provided. .. class:: Tag(parser, token) The ``Tag`` class is nothing other than a subclass of :class:`django.template.Node` which handles argument parsing in it's :meth:`__init__` method rather than an external function. In a normal use case you should only override :attr:`name`, :attr:`options` and :meth:`render_tag`. .. note:: When registering your template tag, register the class object, *not* an instance of it. .. attribute:: name The name of this tag (for use in templates). This attribute is optional and if not provided, the un-camelcase class name will be used instead. So MyTag becomes my_tag. .. attribute:: options An instance of :class:`classytags.core.Options` which holds the options of this tag. .. method:: __init__(parser, token): .. warning:: This is an internal method. It is only documented here for those who would like to extend django-classy-tags. This is where the arguments to this tag get parsed. It's the equivalent to a *compile function* in Django's standard templating system. This method does nothing else but assing the :attr:`kwargs` and :attr:`blocks` attributes to the output of :meth:`options.parse` with the given *parser* and *token*. .. method:: render(context) .. warning:: This is an internal method. It is only documented here for those who would like to extend django-classy-tags. This method resolves the arguments to this tag against the context and then calls :meth:`render_tag` with the context and those arguments and returns the return value of that method. .. method:: render_tag(context[, **kwargs]) The method used to render this tag for a given context. *kwargs* is a dictionary of the (already resolved) options of this tag as well as the blocks (as nodelists) this tag parses until if any are given. This method should return a string. **************************** :mod:`classytags.exceptions` **************************** .. module:: classytags.exceptions This module contains the custom exceptions used by django-classy-tags. .. exception:: BaseError The base class for all custom excpetions, should never be raised directly. .. exception:: ArgumentRequiredError(argument, tagname) Gets raised if an option of a tag is required but not provided. .. exception:: InvalidFlag(argname, actual_value, allowed_values, tagname) Gets raised if a given value for a flag option is neither in *true_values* nor *false_values*. .. exception:: BreakpointExpected(tagname, breakpoints, got) Gets raised if a breakpoint was expected, but another argument was found. .. exception:: TooManyArguments(tagname, extra) Gets raised if too many arguments are provided for a tag. ************************* :mod:`classytags.helpers` ************************* .. module:: classytags.helpers This modules contains helper classes to make building template tags even easier. .. class:: AsTag A helper tag base class to build 'as varname' tags. Note that the option class still has to contain the 'as varname' information. This tag will use the last argument in the options class to set the value into the context. This class implements the method :meth:`classytags.helpers.AsTag.get_value` which gets the context and all arguments except for the varname argument as arguments. It should always return the value this tag comes up with, the class then takes care of either putting the value into the context or returns it if the varname argument is not provided. .. note:: You should not override the :meth:`render_tag` method of this class. .. method:: get_value(context, **kwargs) Should return the value of this tag. The context setting is done in the :meth:`classytags.core.Tag.render_tag` method of this class. .. class:: InclusionTag A helper class for writing inclusion tags (template tags which render a template). .. note:: You should not override the :meth:`render_tag` method of this class. .. attribute:: template The template to use if :meth:`get_template` is not overridden. .. attribute:: push_pop_context By default, this is ``True``. If it's set to ``False`` the context will not be pushed and popped around the rendering of the included template, possibly resulting in context pollution. .. method:: get_template(context, **kwargs) This method should return a template (path) for this context and arguments. By default returns the value of :attr:`template`. .. method:: get_context(context, **kwargs) Should return the context (as a dictionary or an instance of :class:`django.template.Context` or a subclass of it) to use to render the template. By default returns an empty dictionary. ************************ :mod:`classytags.parser` ************************ .. module:: classytags.parser The default argument parser lies here. .. class:: Parser(options) The default argument parser class. It get's initialized with an instance of :class:`classytags.utils.StructuredOptions`. .. attribute:: options The :class:`classytags.utils.StructuredOptions` instance given when the parser was instantiated. .. attribute:: parser The (template) parser used to parse this tag. .. attribute:: bits The split tokens. .. attribute:: tagname Name of this tag. .. attribute:: kwargs The data extracted from the bits. .. attribute:: blocks A dictionary holding the block nodelists. .. attribute:: arguments The arguments in the current breakpoint scope. .. attribute:: current_argument The current argument if any. .. attribute:: todo Remaining bits. Used for more helpful exception messages. .. method:: parse(parser, token) Parses a token stream. This is called when your template tag is parsed. .. method:: handle_bit(bit) Handle the current bit (token). .. method:: handle_next_breakpoint(bit) The current bit is the next breakpoint. Make sure the current scope can be finished successfully and shift to the next one. .. method:: handle_breakpoints(bit) The current bit is a future breakpoint, try to close all breakpoint scopes before that breakpoint and shift to it. .. method:: handle_argument(bit) The current bit is an argument. Handle it and contribute to :attr:`kwargs`. .. method:: parse_blocks() Parses the blocks this tag wants to parse until if any are provided. .. method:: finish() After all bits have been parsed, finish all remaining breakpoint scopes. .. method:: check_required() A helper method to check if there's any required arguments left in the current breakpoint scope. Raises a :exc:`classytags.exceptions.ArgumentRequiredError` if one is found and contributes all optional arguments to :attr:`kwargs`. *********************** :mod:`classytags.utils` *********************** .. module:: classytags.utils Utility classes and methods for django-classy-tags. .. class:: NULL A pseudo type. .. class:: TemplateConstant(value) A constant pseudo template variable which always returns it's initial value when resolved. .. attribute:: literal Used by the :class:`classytags.blocks.VariableBlockName` to generate it's final name. .. class:: StructuredOptions(options, breakpoints) A helper class to organize options. .. attribute:: options The arguments in this options. .. attribute:: breakpoints A *copy* of the breakpoints in this options .. attribute:: blocks A *copy* of the list of tuples (blockname, alias) of blocks of this tag. .. attribute:: current_breakpoint The current breakpoint. .. attribute:: next_breakpoint The next breakpoint (if there is any). .. method:: shift_breakpoint() Shift to the next breakpoint and update :attr:`current_breakpoint` and :attr:`next_breakpoint`. .. method:: get_arguments() Returns a copy of the arguments in the current breakpoint scope. .. class:: ResolvableList(item) A subclass of list which resolves all it's items against a context when it's resolve method gets called. .. function:: get_default_name(name) Turns 'CamelCase' into 'camel_case'. ************************ :mod:`classytags.values` ************************ .. module:: classytags.values .. class:: StringValue(var) .. attribute:: errors A dictionary holding error messages which can be caused by this value class. Defaults to an empty dictionary. .. attribute:: value_on_error The value to use when the validation of a input value fails in non-debug mode. Defaults to an empty string. .. attribute:: var The variable wrapped by this value instance. .. method:: resolve(context) Resolve :attr:`var` against *context* and validate it by calling the :meth:`clean` method with the resolved value. .. method:: clean(value) Validates and/or cleans a resolved value. This method should always return something. If validation fails, the :meth:`error` helper method should be used to properly handle debug modes. .. method:: error(value, category) Handles an error in *category* caused by *value*. In debug mode this will cause a :exc:`django.template.TemplateSyntaxError` to be raised, otherwise a `TemplateSyntaxWarning` is called and :attr:`value_on_error` is returned. The message to be used for both the exception and the warning will be constructed by the message in :attr:`errors` if *category* is in it. The value can be used as a named string formatting parameter. .. class:: IntegerValue(var) Subclass of :class:`StringValue`. .. method:: clean(value) Tries to convert the value to an integer. .. class:: ListValue(value) Subclass of :class:`StringValue` and :class:`list`. Appends the initial value to itself in initialization. .. method:: resolve(context) Resolves all items in itself against *context* and calls :meth:`clean` with the list of resolved values. .. class:: DictValue(dict) Subclass of :class:`StringValue` and :class:`dict`. .. method:: resolve(context) Resolves all *values* against *context* and calls :meth:`clean` with the resolved dictionary.