| """Default tags used by the template system, available to all templates.""" |
| |
| import sys |
| import re |
| from itertools import cycle as itertools_cycle |
| try: |
| reversed |
| except NameError: |
| from django.utils.itercompat import reversed # Python 2.3 fallback |
| |
| from django.template import Node, NodeList, Template, Context, Variable |
| from django.template import TemplateSyntaxError, VariableDoesNotExist, BLOCK_TAG_START, BLOCK_TAG_END, VARIABLE_TAG_START, VARIABLE_TAG_END, SINGLE_BRACE_START, SINGLE_BRACE_END, COMMENT_TAG_START, COMMENT_TAG_END |
| from django.template import get_library, Library, InvalidTemplateLibrary |
| from django.conf import settings |
| from django.utils.encoding import smart_str, smart_unicode |
| from django.utils.itercompat import groupby |
| from django.utils.safestring import mark_safe |
| |
| register = Library() |
| |
| class AutoEscapeControlNode(Node): |
| """Implements the actions of the autoescape tag.""" |
| def __init__(self, setting, nodelist): |
| self.setting, self.nodelist = setting, nodelist |
| |
| def render(self, context): |
| old_setting = context.autoescape |
| context.autoescape = self.setting |
| output = self.nodelist.render(context) |
| context.autoescape = old_setting |
| if self.setting: |
| return mark_safe(output) |
| else: |
| return output |
| |
| class CommentNode(Node): |
| def render(self, context): |
| return '' |
| |
| class CycleNode(Node): |
| def __init__(self, cyclevars, variable_name=None): |
| self.cycle_iter = itertools_cycle([Variable(v) for v in cyclevars]) |
| self.variable_name = variable_name |
| |
| def render(self, context): |
| value = self.cycle_iter.next().resolve(context) |
| if self.variable_name: |
| context[self.variable_name] = value |
| return value |
| |
| class DebugNode(Node): |
| def render(self, context): |
| from pprint import pformat |
| output = [pformat(val) for val in context] |
| output.append('\n\n') |
| output.append(pformat(sys.modules)) |
| return ''.join(output) |
| |
| class FilterNode(Node): |
| def __init__(self, filter_expr, nodelist): |
| self.filter_expr, self.nodelist = filter_expr, nodelist |
| |
| def render(self, context): |
| output = self.nodelist.render(context) |
| # Apply filters. |
| context.update({'var': output}) |
| filtered = self.filter_expr.resolve(context) |
| context.pop() |
| return filtered |
| |
| class FirstOfNode(Node): |
| def __init__(self, vars): |
| self.vars = map(Variable, vars) |
| |
| def render(self, context): |
| for var in self.vars: |
| try: |
| value = var.resolve(context) |
| except VariableDoesNotExist: |
| continue |
| if value: |
| return smart_unicode(value) |
| return u'' |
| |
| class ForNode(Node): |
| def __init__(self, loopvars, sequence, is_reversed, nodelist_loop): |
| self.loopvars, self.sequence = loopvars, sequence |
| self.is_reversed = is_reversed |
| self.nodelist_loop = nodelist_loop |
| |
| def __repr__(self): |
| reversed_text = self.is_reversed and ' reversed' or '' |
| return "<For Node: for %s in %s, tail_len: %d%s>" % \ |
| (', '.join(self.loopvars), self.sequence, len(self.nodelist_loop), |
| reversed_text) |
| |
| def __iter__(self): |
| for node in self.nodelist_loop: |
| yield node |
| |
| def get_nodes_by_type(self, nodetype): |
| nodes = [] |
| if isinstance(self, nodetype): |
| nodes.append(self) |
| nodes.extend(self.nodelist_loop.get_nodes_by_type(nodetype)) |
| return nodes |
| |
| def render(self, context): |
| nodelist = NodeList() |
| if 'forloop' in context: |
| parentloop = context['forloop'] |
| else: |
| parentloop = {} |
| context.push() |
| try: |
| values = self.sequence.resolve(context, True) |
| except VariableDoesNotExist: |
| values = [] |
| if values is None: |
| values = [] |
| if not hasattr(values, '__len__'): |
| values = list(values) |
| len_values = len(values) |
| if self.is_reversed: |
| values = reversed(values) |
| unpack = len(self.loopvars) > 1 |
| # Create a forloop value in the context. We'll update counters on each |
| # iteration just below. |
| loop_dict = context['forloop'] = {'parentloop': parentloop} |
| for i, item in enumerate(values): |
| # Shortcuts for current loop iteration number. |
| loop_dict['counter0'] = i |
| loop_dict['counter'] = i+1 |
| # Reverse counter iteration numbers. |
| loop_dict['revcounter'] = len_values - i |
| loop_dict['revcounter0'] = len_values - i - 1 |
| # Boolean values designating first and last times through loop. |
| loop_dict['first'] = (i == 0) |
| loop_dict['last'] = (i == len_values - 1) |
| |
| if unpack: |
| # If there are multiple loop variables, unpack the item into |
| # them. |
| context.update(dict(zip(self.loopvars, item))) |
| else: |
| context[self.loopvars[0]] = item |
| for node in self.nodelist_loop: |
| nodelist.append(node.render(context)) |
| if unpack: |
| # The loop variables were pushed on to the context so pop them |
| # off again. This is necessary because the tag lets the length |
| # of loopvars differ to the length of each set of items and we |
| # don't want to leave any vars from the previous loop on the |
| # context. |
| context.pop() |
| context.pop() |
| return nodelist.render(context) |
| |
| class IfChangedNode(Node): |
| def __init__(self, nodelist_true, nodelist_false, *varlist): |
| self.nodelist_true, self.nodelist_false = nodelist_true, nodelist_false |
| self._last_seen = None |
| self._varlist = map(Variable, varlist) |
| self._id = str(id(self)) |
| |
| def render(self, context): |
| if 'forloop' in context and self._id not in context['forloop']: |
| self._last_seen = None |
| context['forloop'][self._id] = 1 |
| try: |
| if self._varlist: |
| # Consider multiple parameters. This automatically behaves |
| # like an OR evaluation of the multiple variables. |
| compare_to = [var.resolve(context) for var in self._varlist] |
| else: |
| compare_to = self.nodelist_true.render(context) |
| except VariableDoesNotExist: |
| compare_to = None |
| |
| if compare_to != self._last_seen: |
| firstloop = (self._last_seen == None) |
| self._last_seen = compare_to |
| context.push() |
| context['ifchanged'] = {'firstloop': firstloop} |
| content = self.nodelist_true.render(context) |
| context.pop() |
| return content |
| elif self.nodelist_false: |
| return self.nodelist_false.render(context) |
| return '' |
| |
| class IfEqualNode(Node): |
| def __init__(self, var1, var2, nodelist_true, nodelist_false, negate): |
| self.var1, self.var2 = Variable(var1), Variable(var2) |
| self.nodelist_true, self.nodelist_false = nodelist_true, nodelist_false |
| self.negate = negate |
| |
| def __repr__(self): |
| return "<IfEqualNode>" |
| |
| def render(self, context): |
| try: |
| val1 = self.var1.resolve(context) |
| except VariableDoesNotExist: |
| val1 = None |
| try: |
| val2 = self.var2.resolve(context) |
| except VariableDoesNotExist: |
| val2 = None |
| if (self.negate and val1 != val2) or (not self.negate and val1 == val2): |
| return self.nodelist_true.render(context) |
| return self.nodelist_false.render(context) |
| |
| class IfNode(Node): |
| def __init__(self, bool_exprs, nodelist_true, nodelist_false, link_type): |
| self.bool_exprs = bool_exprs |
| self.nodelist_true, self.nodelist_false = nodelist_true, nodelist_false |
| self.link_type = link_type |
| |
| def __repr__(self): |
| return "<If node>" |
| |
| def __iter__(self): |
| for node in self.nodelist_true: |
| yield node |
| for node in self.nodelist_false: |
| yield node |
| |
| def get_nodes_by_type(self, nodetype): |
| nodes = [] |
| if isinstance(self, nodetype): |
| nodes.append(self) |
| nodes.extend(self.nodelist_true.get_nodes_by_type(nodetype)) |
| nodes.extend(self.nodelist_false.get_nodes_by_type(nodetype)) |
| return nodes |
| |
| def render(self, context): |
| if self.link_type == IfNode.LinkTypes.or_: |
| for ifnot, bool_expr in self.bool_exprs: |
| try: |
| value = bool_expr.resolve(context, True) |
| except VariableDoesNotExist: |
| value = None |
| if (value and not ifnot) or (ifnot and not value): |
| return self.nodelist_true.render(context) |
| return self.nodelist_false.render(context) |
| else: |
| for ifnot, bool_expr in self.bool_exprs: |
| try: |
| value = bool_expr.resolve(context, True) |
| except VariableDoesNotExist: |
| value = None |
| if not ((value and not ifnot) or (ifnot and not value)): |
| return self.nodelist_false.render(context) |
| return self.nodelist_true.render(context) |
| |
| class LinkTypes: |
| and_ = 0, |
| or_ = 1 |
| |
| class RegroupNode(Node): |
| def __init__(self, target, expression, var_name): |
| self.target, self.expression = target, expression |
| self.var_name = var_name |
| |
| def render(self, context): |
| obj_list = self.target.resolve(context, True) |
| if obj_list == None: |
| # target variable wasn't found in context; fail silently. |
| context[self.var_name] = [] |
| return '' |
| # List of dictionaries in the format: |
| # {'grouper': 'key', 'list': [list of contents]}. |
| context[self.var_name] = [ |
| {'grouper': key, 'list': list(val)} |
| for key, val in |
| groupby(obj_list, lambda v, f=self.expression.resolve: f(v, True)) |
| ] |
| return '' |
| |
| def include_is_allowed(filepath): |
| for root in settings.ALLOWED_INCLUDE_ROOTS: |
| if filepath.startswith(root): |
| return True |
| return False |
| |
| class SsiNode(Node): |
| def __init__(self, filepath, parsed): |
| self.filepath, self.parsed = filepath, parsed |
| |
| def render(self, context): |
| if not include_is_allowed(self.filepath): |
| if settings.DEBUG: |
| return "[Didn't have permission to include file]" |
| else: |
| return '' # Fail silently for invalid includes. |
| try: |
| fp = open(self.filepath, 'r') |
| output = fp.read() |
| fp.close() |
| except IOError: |
| output = '' |
| if self.parsed: |
| try: |
| t = Template(output, name=self.filepath) |
| return t.render(context) |
| except TemplateSyntaxError, e: |
| if settings.DEBUG: |
| return "[Included template had syntax error: %s]" % e |
| else: |
| return '' # Fail silently for invalid included templates. |
| return output |
| |
| class LoadNode(Node): |
| def render(self, context): |
| return '' |
| |
| class NowNode(Node): |
| def __init__(self, format_string): |
| self.format_string = format_string |
| |
| def render(self, context): |
| from datetime import datetime |
| from django.utils.dateformat import DateFormat |
| df = DateFormat(datetime.now()) |
| return df.format(self.format_string) |
| |
| class SpacelessNode(Node): |
| def __init__(self, nodelist): |
| self.nodelist = nodelist |
| |
| def render(self, context): |
| from django.utils.html import strip_spaces_between_tags |
| return strip_spaces_between_tags(self.nodelist.render(context).strip()) |
| |
| class TemplateTagNode(Node): |
| mapping = {'openblock': BLOCK_TAG_START, |
| 'closeblock': BLOCK_TAG_END, |
| 'openvariable': VARIABLE_TAG_START, |
| 'closevariable': VARIABLE_TAG_END, |
| 'openbrace': SINGLE_BRACE_START, |
| 'closebrace': SINGLE_BRACE_END, |
| 'opencomment': COMMENT_TAG_START, |
| 'closecomment': COMMENT_TAG_END, |
| } |
| |
| def __init__(self, tagtype): |
| self.tagtype = tagtype |
| |
| def render(self, context): |
| return self.mapping.get(self.tagtype, '') |
| |
| class URLNode(Node): |
| def __init__(self, view_name, args, kwargs): |
| self.view_name = view_name |
| self.args = args |
| self.kwargs = kwargs |
| |
| def render(self, context): |
| from django.core.urlresolvers import reverse, NoReverseMatch |
| args = [arg.resolve(context) for arg in self.args] |
| kwargs = dict([(smart_str(k,'ascii'), v.resolve(context)) |
| for k, v in self.kwargs.items()]) |
| try: |
| return reverse(self.view_name, args=args, kwargs=kwargs) |
| except NoReverseMatch: |
| project_name = settings.SETTINGS_MODULE.split('.')[0] |
| return reverse(project_name + '.' + self.view_name, |
| args=args, kwargs=kwargs) |
| |
| class WidthRatioNode(Node): |
| def __init__(self, val_expr, max_expr, max_width): |
| self.val_expr = val_expr |
| self.max_expr = max_expr |
| self.max_width = max_width |
| |
| def render(self, context): |
| try: |
| value = self.val_expr.resolve(context) |
| maxvalue = self.max_expr.resolve(context) |
| except VariableDoesNotExist: |
| return '' |
| try: |
| value = float(value) |
| maxvalue = float(maxvalue) |
| ratio = (value / maxvalue) * int(self.max_width) |
| except (ValueError, ZeroDivisionError): |
| return '' |
| return str(int(round(ratio))) |
| |
| class WithNode(Node): |
| def __init__(self, var, name, nodelist): |
| self.var = var |
| self.name = name |
| self.nodelist = nodelist |
| |
| def __repr__(self): |
| return "<WithNode>" |
| |
| def render(self, context): |
| val = self.var.resolve(context) |
| context.push() |
| context[self.name] = val |
| output = self.nodelist.render(context) |
| context.pop() |
| return output |
| |
| #@register.tag |
| def autoescape(parser, token): |
| """ |
| Force autoescape behaviour for this block. |
| """ |
| args = token.contents.split() |
| if len(args) != 2: |
| raise TemplateSyntaxError("'Autoescape' tag requires exactly one argument.") |
| arg = args[1] |
| if arg not in (u'on', u'off'): |
| raise TemplateSyntaxError("'Autoescape' argument should be 'on' or 'off'") |
| nodelist = parser.parse(('endautoescape',)) |
| parser.delete_first_token() |
| return AutoEscapeControlNode((arg == 'on'), nodelist) |
| autoescape = register.tag(autoescape) |
| |
| #@register.tag |
| def comment(parser, token): |
| """ |
| Ignores everything between ``{% comment %}`` and ``{% endcomment %}``. |
| """ |
| parser.skip_past('endcomment') |
| return CommentNode() |
| comment = register.tag(comment) |
| |
| #@register.tag |
| def cycle(parser, token): |
| """ |
| Cycles among the given strings each time this tag is encountered. |
| |
| Within a loop, cycles among the given strings each time through |
| the loop:: |
| |
| {% for o in some_list %} |
| <tr class="{% cycle 'row1' 'row2' %}"> |
| ... |
| </tr> |
| {% endfor %} |
| |
| Outside of a loop, give the values a unique name the first time you call |
| it, then use that name each sucessive time through:: |
| |
| <tr class="{% cycle 'row1' 'row2' 'row3' as rowcolors %}">...</tr> |
| <tr class="{% cycle rowcolors %}">...</tr> |
| <tr class="{% cycle rowcolors %}">...</tr> |
| |
| You can use any number of values, separated by spaces. Commas can also |
| be used to separate values; if a comma is used, the cycle values are |
| interpreted as literal strings. |
| """ |
| |
| # Note: This returns the exact same node on each {% cycle name %} call; |
| # that is, the node object returned from {% cycle a b c as name %} and the |
| # one returned from {% cycle name %} are the exact same object. This |
| # shouldn't cause problems (heh), but if it does, now you know. |
| # |
| # Ugly hack warning: This stuffs the named template dict into parser so |
| # that names are only unique within each template (as opposed to using |
| # a global variable, which would make cycle names have to be unique across |
| # *all* templates. |
| |
| args = token.split_contents() |
| |
| if len(args) < 2: |
| raise TemplateSyntaxError("'cycle' tag requires at least two arguments") |
| |
| if ',' in args[1]: |
| # Backwards compatibility: {% cycle a,b %} or {% cycle a,b as foo %} |
| # case. |
| args[1:2] = ['"%s"' % arg for arg in args[1].split(",")] |
| |
| if len(args) == 2: |
| # {% cycle foo %} case. |
| name = args[1] |
| if not hasattr(parser, '_namedCycleNodes'): |
| raise TemplateSyntaxError("No named cycles in template. '%s' is not defined" % name) |
| if not name in parser._namedCycleNodes: |
| raise TemplateSyntaxError("Named cycle '%s' does not exist" % name) |
| return parser._namedCycleNodes[name] |
| |
| if len(args) > 4 and args[-2] == 'as': |
| name = args[-1] |
| node = CycleNode(args[1:-2], name) |
| if not hasattr(parser, '_namedCycleNodes'): |
| parser._namedCycleNodes = {} |
| parser._namedCycleNodes[name] = node |
| else: |
| node = CycleNode(args[1:]) |
| return node |
| cycle = register.tag(cycle) |
| |
| def debug(parser, token): |
| """ |
| Outputs a whole load of debugging information, including the current |
| context and imported modules. |
| |
| Sample usage:: |
| |
| <pre> |
| {% debug %} |
| </pre> |
| """ |
| return DebugNode() |
| debug = register.tag(debug) |
| |
| #@register.tag(name="filter") |
| def do_filter(parser, token): |
| """ |
| Filters the contents of the block through variable filters. |
| |
| Filters can also be piped through each other, and they can have |
| arguments -- just like in variable syntax. |
| |
| Sample usage:: |
| |
| {% filter force_escape|lower %} |
| This text will be HTML-escaped, and will appear in lowercase. |
| {% endfilter %} |
| """ |
| _, rest = token.contents.split(None, 1) |
| filter_expr = parser.compile_filter("var|%s" % (rest)) |
| for func, unused in filter_expr.filters: |
| if getattr(func, '_decorated_function', func).__name__ in ('escape', 'safe'): |
| raise TemplateSyntaxError('"filter %s" is not permitted. Use the "autoescape" tag instead.' % func.__name__) |
| nodelist = parser.parse(('endfilter',)) |
| parser.delete_first_token() |
| return FilterNode(filter_expr, nodelist) |
| do_filter = register.tag("filter", do_filter) |
| |
| #@register.tag |
| def firstof(parser, token): |
| """ |
| Outputs the first variable passed that is not False. |
| |
| Outputs nothing if all the passed variables are False. |
| |
| Sample usage:: |
| |
| {% firstof var1 var2 var3 %} |
| |
| This is equivalent to:: |
| |
| {% if var1 %} |
| {{ var1 }} |
| {% else %}{% if var2 %} |
| {{ var2 }} |
| {% else %}{% if var3 %} |
| {{ var3 }} |
| {% endif %}{% endif %}{% endif %} |
| |
| but obviously much cleaner! |
| |
| You can also use a literal string as a fallback value in case all |
| passed variables are False:: |
| |
| {% firstof var1 var2 var3 "fallback value" %} |
| |
| """ |
| bits = token.split_contents()[1:] |
| if len(bits) < 1: |
| raise TemplateSyntaxError("'firstof' statement requires at least one" |
| " argument") |
| return FirstOfNode(bits) |
| firstof = register.tag(firstof) |
| |
| #@register.tag(name="for") |
| def do_for(parser, token): |
| """ |
| Loops over each item in an array. |
| |
| For example, to display a list of athletes given ``athlete_list``:: |
| |
| <ul> |
| {% for athlete in athlete_list %} |
| <li>{{ athlete.name }}</li> |
| {% endfor %} |
| </ul> |
| |
| You can loop over a list in reverse by using |
| ``{% for obj in list reversed %}``. |
| |
| You can also unpack multiple values from a two-dimensional array:: |
| |
| {% for key,value in dict.items %} |
| {{ key }}: {{ value }} |
| {% endfor %} |
| |
| The for loop sets a number of variables available within the loop: |
| |
| ========================== ================================================ |
| Variable Description |
| ========================== ================================================ |
| ``forloop.counter`` The current iteration of the loop (1-indexed) |
| ``forloop.counter0`` The current iteration of the loop (0-indexed) |
| ``forloop.revcounter`` The number of iterations from the end of the |
| loop (1-indexed) |
| ``forloop.revcounter0`` The number of iterations from the end of the |
| loop (0-indexed) |
| ``forloop.first`` True if this is the first time through the loop |
| ``forloop.last`` True if this is the last time through the loop |
| ``forloop.parentloop`` For nested loops, this is the loop "above" the |
| current one |
| ========================== ================================================ |
| |
| """ |
| bits = token.contents.split() |
| if len(bits) < 4: |
| raise TemplateSyntaxError("'for' statements should have at least four" |
| " words: %s" % token.contents) |
| |
| is_reversed = bits[-1] == 'reversed' |
| in_index = is_reversed and -3 or -2 |
| if bits[in_index] != 'in': |
| raise TemplateSyntaxError("'for' statements should use the format" |
| " 'for x in y': %s" % token.contents) |
| |
| loopvars = re.sub(r' *, *', ',', ' '.join(bits[1:in_index])).split(',') |
| for var in loopvars: |
| if not var or ' ' in var: |
| raise TemplateSyntaxError("'for' tag received an invalid argument:" |
| " %s" % token.contents) |
| |
| sequence = parser.compile_filter(bits[in_index+1]) |
| nodelist_loop = parser.parse(('endfor',)) |
| parser.delete_first_token() |
| return ForNode(loopvars, sequence, is_reversed, nodelist_loop) |
| do_for = register.tag("for", do_for) |
| |
| def do_ifequal(parser, token, negate): |
| bits = list(token.split_contents()) |
| if len(bits) != 3: |
| raise TemplateSyntaxError, "%r takes two arguments" % bits[0] |
| end_tag = 'end' + bits[0] |
| nodelist_true = parser.parse(('else', end_tag)) |
| token = parser.next_token() |
| if token.contents == 'else': |
| nodelist_false = parser.parse((end_tag,)) |
| parser.delete_first_token() |
| else: |
| nodelist_false = NodeList() |
| return IfEqualNode(bits[1], bits[2], nodelist_true, nodelist_false, negate) |
| |
| #@register.tag |
| def ifequal(parser, token): |
| """ |
| Outputs the contents of the block if the two arguments equal each other. |
| |
| Examples:: |
| |
| {% ifequal user.id comment.user_id %} |
| ... |
| {% endifequal %} |
| |
| {% ifnotequal user.id comment.user_id %} |
| ... |
| {% else %} |
| ... |
| {% endifnotequal %} |
| """ |
| return do_ifequal(parser, token, False) |
| ifequal = register.tag(ifequal) |
| |
| #@register.tag |
| def ifnotequal(parser, token): |
| """ |
| Outputs the contents of the block if the two arguments are not equal. |
| See ifequal. |
| """ |
| return do_ifequal(parser, token, True) |
| ifnotequal = register.tag(ifnotequal) |
| |
| #@register.tag(name="if") |
| def do_if(parser, token): |
| """ |
| The ``{% if %}`` tag evaluates a variable, and if that variable is "true" |
| (i.e., exists, is not empty, and is not a false boolean value), the |
| contents of the block are output: |
| |
| :: |
| |
| {% if athlete_list %} |
| Number of athletes: {{ athlete_list|count }} |
| {% else %} |
| No athletes. |
| {% endif %} |
| |
| In the above, if ``athlete_list`` is not empty, the number of athletes will |
| be displayed by the ``{{ athlete_list|count }}`` variable. |
| |
| As you can see, the ``if`` tag can take an option ``{% else %}`` clause |
| that will be displayed if the test fails. |
| |
| ``if`` tags may use ``or``, ``and`` or ``not`` to test a number of |
| variables or to negate a given variable:: |
| |
| {% if not athlete_list %} |
| There are no athletes. |
| {% endif %} |
| |
| {% if athlete_list or coach_list %} |
| There are some athletes or some coaches. |
| {% endif %} |
| |
| {% if athlete_list and coach_list %} |
| Both atheletes and coaches are available. |
| {% endif %} |
| |
| {% if not athlete_list or coach_list %} |
| There are no athletes, or there are some coaches. |
| {% endif %} |
| |
| {% if athlete_list and not coach_list %} |
| There are some athletes and absolutely no coaches. |
| {% endif %} |
| |
| ``if`` tags do not allow ``and`` and ``or`` clauses with the same tag, |
| because the order of logic would be ambigous. For example, this is |
| invalid:: |
| |
| {% if athlete_list and coach_list or cheerleader_list %} |
| |
| If you need to combine ``and`` and ``or`` to do advanced logic, just use |
| nested if tags. For example:: |
| |
| {% if athlete_list %} |
| {% if coach_list or cheerleader_list %} |
| We have athletes, and either coaches or cheerleaders! |
| {% endif %} |
| {% endif %} |
| """ |
| bits = token.contents.split() |
| del bits[0] |
| if not bits: |
| raise TemplateSyntaxError("'if' statement requires at least one argument") |
| # Bits now looks something like this: ['a', 'or', 'not', 'b', 'or', 'c.d'] |
| bitstr = ' '.join(bits) |
| boolpairs = bitstr.split(' and ') |
| boolvars = [] |
| if len(boolpairs) == 1: |
| link_type = IfNode.LinkTypes.or_ |
| boolpairs = bitstr.split(' or ') |
| else: |
| link_type = IfNode.LinkTypes.and_ |
| if ' or ' in bitstr: |
| raise TemplateSyntaxError, "'if' tags can't mix 'and' and 'or'" |
| for boolpair in boolpairs: |
| if ' ' in boolpair: |
| try: |
| not_, boolvar = boolpair.split() |
| except ValueError: |
| raise TemplateSyntaxError, "'if' statement improperly formatted" |
| if not_ != 'not': |
| raise TemplateSyntaxError, "Expected 'not' in if statement" |
| boolvars.append((True, parser.compile_filter(boolvar))) |
| else: |
| boolvars.append((False, parser.compile_filter(boolpair))) |
| nodelist_true = parser.parse(('else', 'endif')) |
| token = parser.next_token() |
| if token.contents == 'else': |
| nodelist_false = parser.parse(('endif',)) |
| parser.delete_first_token() |
| else: |
| nodelist_false = NodeList() |
| return IfNode(boolvars, nodelist_true, nodelist_false, link_type) |
| do_if = register.tag("if", do_if) |
| |
| #@register.tag |
| def ifchanged(parser, token): |
| """ |
| Checks if a value has changed from the last iteration of a loop. |
| |
| The 'ifchanged' block tag is used within a loop. It has two possible uses. |
| |
| 1. Checks its own rendered contents against its previous state and only |
| displays the content if it has changed. For example, this displays a |
| list of days, only displaying the month if it changes:: |
| |
| <h1>Archive for {{ year }}</h1> |
| |
| {% for date in days %} |
| {% ifchanged %}<h3>{{ date|date:"F" }}</h3>{% endifchanged %} |
| <a href="{{ date|date:"M/d"|lower }}/">{{ date|date:"j" }}</a> |
| {% endfor %} |
| |
| 2. If given a variable, check whether that variable has changed. |
| For example, the following shows the date every time it changes, but |
| only shows the hour if both the hour and the date have changed:: |
| |
| {% for date in days %} |
| {% ifchanged date.date %} {{ date.date }} {% endifchanged %} |
| {% ifchanged date.hour date.date %} |
| {{ date.hour }} |
| {% endifchanged %} |
| {% endfor %} |
| """ |
| bits = token.contents.split() |
| nodelist_true = parser.parse(('else', 'endifchanged')) |
| token = parser.next_token() |
| if token.contents == 'else': |
| nodelist_false = parser.parse(('endifchanged',)) |
| parser.delete_first_token() |
| else: |
| nodelist_false = NodeList() |
| return IfChangedNode(nodelist_true, nodelist_false, *bits[1:]) |
| ifchanged = register.tag(ifchanged) |
| |
| #@register.tag |
| def ssi(parser, token): |
| """ |
| Outputs the contents of a given file into the page. |
| |
| Like a simple "include" tag, the ``ssi`` tag includes the contents |
| of another file -- which must be specified using an absolute path -- |
| in the current page:: |
| |
| {% ssi /home/html/ljworld.com/includes/right_generic.html %} |
| |
| If the optional "parsed" parameter is given, the contents of the included |
| file are evaluated as template code, with the current context:: |
| |
| {% ssi /home/html/ljworld.com/includes/right_generic.html parsed %} |
| """ |
| bits = token.contents.split() |
| parsed = False |
| if len(bits) not in (2, 3): |
| raise TemplateSyntaxError("'ssi' tag takes one argument: the path to" |
| " the file to be included") |
| if len(bits) == 3: |
| if bits[2] == 'parsed': |
| parsed = True |
| else: |
| raise TemplateSyntaxError("Second (optional) argument to %s tag" |
| " must be 'parsed'" % bits[0]) |
| return SsiNode(bits[1], parsed) |
| ssi = register.tag(ssi) |
| |
| #@register.tag |
| def load(parser, token): |
| """ |
| Loads a custom template tag set. |
| |
| For example, to load the template tags in |
| ``django/templatetags/news/photos.py``:: |
| |
| {% load news.photos %} |
| """ |
| bits = token.contents.split() |
| for taglib in bits[1:]: |
| # add the library to the parser |
| try: |
| lib = get_library("django.templatetags.%s" % taglib) |
| parser.add_library(lib) |
| except InvalidTemplateLibrary, e: |
| raise TemplateSyntaxError("'%s' is not a valid tag library: %s" % |
| (taglib, e)) |
| return LoadNode() |
| load = register.tag(load) |
| |
| #@register.tag |
| def now(parser, token): |
| """ |
| Displays the date, formatted according to the given string. |
| |
| Uses the same format as PHP's ``date()`` function; see http://php.net/date |
| for all the possible values. |
| |
| Sample usage:: |
| |
| It is {% now "jS F Y H:i" %} |
| """ |
| bits = token.contents.split('"') |
| if len(bits) != 3: |
| raise TemplateSyntaxError, "'now' statement takes one argument" |
| format_string = bits[1] |
| return NowNode(format_string) |
| now = register.tag(now) |
| |
| #@register.tag |
| def regroup(parser, token): |
| """ |
| Regroups a list of alike objects by a common attribute. |
| |
| This complex tag is best illustrated by use of an example: say that |
| ``people`` is a list of ``Person`` objects that have ``first_name``, |
| ``last_name``, and ``gender`` attributes, and you'd like to display a list |
| that looks like: |
| |
| * Male: |
| * George Bush |
| * Bill Clinton |
| * Female: |
| * Margaret Thatcher |
| * Colendeeza Rice |
| * Unknown: |
| * Pat Smith |
| |
| The following snippet of template code would accomplish this dubious task:: |
| |
| {% regroup people by gender as grouped %} |
| <ul> |
| {% for group in grouped %} |
| <li>{{ group.grouper }} |
| <ul> |
| {% for item in group.list %} |
| <li>{{ item }}</li> |
| {% endfor %} |
| </ul> |
| {% endfor %} |
| </ul> |
| |
| As you can see, ``{% regroup %}`` populates a variable with a list of |
| objects with ``grouper`` and ``list`` attributes. ``grouper`` contains the |
| item that was grouped by; ``list`` contains the list of objects that share |
| that ``grouper``. In this case, ``grouper`` would be ``Male``, ``Female`` |
| and ``Unknown``, and ``list`` is the list of people with those genders. |
| |
| Note that `{% regroup %}`` does not work when the list to be grouped is not |
| sorted by the key you are grouping by! This means that if your list of |
| people was not sorted by gender, you'd need to make sure it is sorted |
| before using it, i.e.:: |
| |
| {% regroup people|dictsort:"gender" by gender as grouped %} |
| |
| """ |
| firstbits = token.contents.split(None, 3) |
| if len(firstbits) != 4: |
| raise TemplateSyntaxError, "'regroup' tag takes five arguments" |
| target = parser.compile_filter(firstbits[1]) |
| if firstbits[2] != 'by': |
| raise TemplateSyntaxError("second argument to 'regroup' tag must be 'by'") |
| lastbits_reversed = firstbits[3][::-1].split(None, 2) |
| if lastbits_reversed[1][::-1] != 'as': |
| raise TemplateSyntaxError("next-to-last argument to 'regroup' tag must" |
| " be 'as'") |
| |
| expression = parser.compile_filter(lastbits_reversed[2][::-1]) |
| |
| var_name = lastbits_reversed[0][::-1] |
| return RegroupNode(target, expression, var_name) |
| regroup = register.tag(regroup) |
| |
| def spaceless(parser, token): |
| """ |
| Removes whitespace between HTML tags, including tab and newline characters. |
| |
| Example usage:: |
| |
| {% spaceless %} |
| <p> |
| <a href="foo/">Foo</a> |
| </p> |
| {% endspaceless %} |
| |
| This example would return this HTML:: |
| |
| <p><a href="foo/">Foo</a></p> |
| |
| Only space between *tags* is normalized -- not space between tags and text. |
| In this example, the space around ``Hello`` won't be stripped:: |
| |
| {% spaceless %} |
| <strong> |
| Hello |
| </strong> |
| {% endspaceless %} |
| """ |
| nodelist = parser.parse(('endspaceless',)) |
| parser.delete_first_token() |
| return SpacelessNode(nodelist) |
| spaceless = register.tag(spaceless) |
| |
| #@register.tag |
| def templatetag(parser, token): |
| """ |
| Outputs one of the bits used to compose template tags. |
| |
| Since the template system has no concept of "escaping", to display one of |
| the bits used in template tags, you must use the ``{% templatetag %}`` tag. |
| |
| The argument tells which template bit to output: |
| |
| ================== ======= |
| Argument Outputs |
| ================== ======= |
| ``openblock`` ``{%`` |
| ``closeblock`` ``%}`` |
| ``openvariable`` ``{{`` |
| ``closevariable`` ``}}`` |
| ``openbrace`` ``{`` |
| ``closebrace`` ``}`` |
| ``opencomment`` ``{#`` |
| ``closecomment`` ``#}`` |
| ================== ======= |
| """ |
| bits = token.contents.split() |
| if len(bits) != 2: |
| raise TemplateSyntaxError, "'templatetag' statement takes one argument" |
| tag = bits[1] |
| if tag not in TemplateTagNode.mapping: |
| raise TemplateSyntaxError("Invalid templatetag argument: '%s'." |
| " Must be one of: %s" % |
| (tag, TemplateTagNode.mapping.keys())) |
| return TemplateTagNode(tag) |
| templatetag = register.tag(templatetag) |
| |
| def url(parser, token): |
| """ |
| Returns an absolute URL matching given view with its parameters. |
| |
| This is a way to define links that aren't tied to a particular URL |
| configuration:: |
| |
| {% url path.to.some_view arg1,arg2,name1=value1 %} |
| |
| The first argument is a path to a view. It can be an absolute python path |
| or just ``app_name.view_name`` without the project name if the view is |
| located inside the project. Other arguments are comma-separated values |
| that will be filled in place of positional and keyword arguments in the |
| URL. All arguments for the URL should be present. |
| |
| For example if you have a view ``app_name.client`` taking client's id and |
| the corresponding line in a URLconf looks like this:: |
| |
| ('^client/(\d+)/$', 'app_name.client') |
| |
| and this app's URLconf is included into the project's URLconf under some |
| path:: |
| |
| ('^clients/', include('project_name.app_name.urls')) |
| |
| then in a template you can create a link for a certain client like this:: |
| |
| {% url app_name.client client.id %} |
| |
| The URL will look like ``/clients/client/123/``. |
| """ |
| bits = token.contents.split(' ', 2) |
| if len(bits) < 2: |
| raise TemplateSyntaxError("'%s' takes at least one argument" |
| " (path to a view)" % bits[0]) |
| args = [] |
| kwargs = {} |
| if len(bits) > 2: |
| for arg in bits[2].split(','): |
| if '=' in arg: |
| k, v = arg.split('=', 1) |
| k = k.strip() |
| kwargs[k] = parser.compile_filter(v) |
| else: |
| args.append(parser.compile_filter(arg)) |
| return URLNode(bits[1], args, kwargs) |
| url = register.tag(url) |
| |
| #@register.tag |
| def widthratio(parser, token): |
| """ |
| For creating bar charts and such, this tag calculates the ratio of a given |
| value to a maximum value, and then applies that ratio to a constant. |
| |
| For example:: |
| |
| <img src='bar.gif' height='10' width='{% widthratio this_value max_value 100 %}' /> |
| |
| Above, if ``this_value`` is 175 and ``max_value`` is 200, the the image in |
| the above example will be 88 pixels wide (because 175/200 = .875; |
| .875 * 100 = 87.5 which is rounded up to 88). |
| """ |
| bits = token.contents.split() |
| if len(bits) != 4: |
| raise TemplateSyntaxError("widthratio takes three arguments") |
| tag, this_value_expr, max_value_expr, max_width = bits |
| try: |
| max_width = int(max_width) |
| except ValueError: |
| raise TemplateSyntaxError("widthratio final argument must be an integer") |
| return WidthRatioNode(parser.compile_filter(this_value_expr), |
| parser.compile_filter(max_value_expr), max_width) |
| widthratio = register.tag(widthratio) |
| |
| #@register.tag |
| def do_with(parser, token): |
| """ |
| Adds a value to the context (inside of this block) for caching and easy |
| access. |
| |
| For example:: |
| |
| {% with person.some_sql_method as total %} |
| {{ total }} object{{ total|pluralize }} |
| {% endwith %} |
| """ |
| bits = list(token.split_contents()) |
| if len(bits) != 4 or bits[2] != "as": |
| raise TemplateSyntaxError("%r expected format is 'value as name'" % |
| bits[0]) |
| var = parser.compile_filter(bits[1]) |
| name = bits[3] |
| nodelist = parser.parse(('endwith',)) |
| parser.delete_first_token() |
| return WithNode(var, name, nodelist) |
| do_with = register.tag('with', do_with) |
