__doc__ = """ YUI_include -- YUI Loader as Django middleware (c) Antti Kaihola 2008 http://djangopeople.net/akaihola/ akaihol+django@ambitone.com This server-side middleware implements some of the functionality in the Yahoo User Interface Loader component. YUI JavaScript and CSS modules requirements can be declared anywhere in the base, inherited or included templates, and the resulting, optimized The markup format can be customized with global Django settings. Example: YUI_INCLUDE_PREFIX_RE = r'{!' YUI_INCLUDE_SUFFIX_RE = r'!}' would change markup to e.g. ``{! init !}`` and ``{! include dom event !}``. The base URL is customized with the ``YUI_INCLUDE_BASE`` setting, e.g.: YUI_INCLUDE_BASE = 'http://localhost:8000/yui/build/' To remove the XHTML trailing slash from the tag, use: YUI_INCLUDE_CSS_TAG = '' """ import re from shlex import shlex from django.conf import settings from module_info_2_5_1 import MODULE_INFO, SKIN from components import Components DEFAULT_BASE = 'http://yui.yahooapis.com/2.5.1/build/' DEFAULT_JS_TAG = '' DEFAULT_CSS_TAG = '' YUI_BASE = getattr(settings, 'YUI_INCLUDE_BASE', DEFAULT_BASE) PREFIX_RE = getattr(settings, 'YUI_INCLUDE_PREFIX_RE', '') TAGS = {'js': getattr(settings, 'YUI_INCLUDE_JS_TAG', DEFAULT_JS_TAG), 'css': getattr(settings, 'YUI_INCLUDE_CSS_TAG', DEFAULT_CSS_TAG)} VERSIONS = {'raw': '', '': '', 'min': '-min', 'debug': '-debug'} class YUILoader: def __init__(self): self._module_info = Components(MODULE_INFO) self._components = set() self._rolled_up_components = {} self._rollup_counters = {} self.set_version('min') def set_version(self, version): self._version = VERSIONS[version] def add_component(self, new_component_name): if not self._has_component(new_component_name): self._add_requirements(new_component_name) self._count_in_rollups(new_component_name) rollup_name = self._get_satisfied_rollup(new_component_name) if rollup_name: self.add_component(rollup_name) else: self._components.add(new_component_name) self._roll_up_superseded(new_component_name) def add_module(self, module_def): module_data = {} lexer = shlex(module_def, posix=True) def expect(*patterns): token = lexer.get_token() if token not in patterns: raise ValueError, '%s expected instead of %s' % \ (' or '.join(repr(s) for s in patterns), token and repr(token) or 'end of data') return token str_attrs = 'name', 'type', 'path', 'fullpath', 'varName' list_attrs = 'requires', 'optional', 'after' state = 'ATTR' expect('{') while state != 'STOP': if state == 'ATTR': token = expect(*str_attrs+list_attrs) expect(':') if token in str_attrs: module_data[token] = lexer.get_token() if module_data[token] is None: raise ValueError, \ 'string expected instead of end of data' state = 'DELIM' elif token in list_attrs: expect('[') lst = module_data[token] = [] state = 'LIST' elif state == 'LIST': lst.append(lexer.get_token()) if re.search(r'\W', lst[-1]): raise ValueError, 'invalid component name %r' % token if expect(',', ']') == ']': state = 'DELIM' elif state == 'DELIM': if expect(',', '}') == '}': expect(None) state = 'STOP' else: state = 'ATTR' if 'type' not in module_data: raise ValueError, 'type missing in %r' % module_def self._module_info.add(module_data['name'], module_data) return module_data def render(self): return '\n'.join(self._render_component(component) for component in self._sort_components()) def _has_component(self, component_name): return component_name in self._components \ or component_name in self._rolled_up_components def _get_satisfied_rollup(self, component_name): if self._version == '-min': for rollup_name in self._module_info.get_rollups(component_name): rollup_status = self._rollup_counters.get(rollup_name, set()) if len(rollup_status) >= self._module_info[rollup_name].rollup: return rollup_name def _count_in_rollups(self, component_name): for rollup_name in self._module_info.get_rollups(component_name): rolled_up = self._rollup_counters.setdefault(rollup_name, set()) rolled_up.add(component_name) for superseded in self._module_info[component_name].supersedes: self._count_in_rollups(superseded) def _roll_up_superseded(self, component_name): for superseded in self._module_info[component_name].supersedes: self._rolled_up_components[superseded] = component_name if superseded in self._components: self._components.remove(superseded) def _add_requirements(self, component_name): component = self._module_info[component_name] for requirement in component.requires: self.add_component(requirement) if component.skinnable: self.add_component(SKIN['defaultSkin']) def _render_component(self, component_name): component = self._module_info[component_name] path = component.fullpath or YUI_BASE + component.path if component.type == 'js': if self._version != '-min' and path.endswith('-min.js'): path = path[:-7] + self._version + '.js' elif component.type == 'css': if self._version == '' and path.endswith('-min.css'): path = path[:-8] + '.css' return TAGS[component.type] % path def _sort_components(self, component_names=None): if component_names is None: comps = self._components.copy() else: comps = component_names while comps: component_name = comps.pop() component = self._module_info[component_name] direct_deps = component.requires + component.after indirect_deps = [ self._rolled_up_components[r] for r in direct_deps if r in self._rolled_up_components] all_deps = set(direct_deps) \ .union(set(indirect_deps)) \ .union(set(component.optional)) deps_left = comps.intersection(all_deps) for r in self._sort_components(deps_left): yield r comps.remove(r) yield component_name YUI_RE = re.compile( r'%s(include|version) +(.*?)%s' % (PREFIX_RE, SUFFIX_RE)) YUI_ADDMODULE_RE = re.compile( r'(?s)%saddModule\s*(\{\s*.*?\s*})\s*%s' % (PREFIX_RE, SUFFIX_RE)) YUI_INIT_RE = re.compile( '%sinit%s' % (PREFIX_RE, SUFFIX_RE)) class YUIIncludeMiddleware(object): def process_response(self, request, response): components = set() loader = YUILoader() def add_module(match): loader.add_module(match.group(1)) return '' content = YUI_ADDMODULE_RE.sub(add_module, response.content) def collect(match): cmd, data = match.groups() if cmd == 'include': components.update(data.split()) elif cmd == 'version': loader.set_version(data) else: return '' % cmd return '' content = YUI_RE.sub(collect, content) for component in components: loader.add_component(component) tags = loader.render() if tags: content, count = YUI_INIT_RE.subn(tags, content, 1) if count != 1: content += ('

%d YUI init tags found,' 'at least one expected

' % count) response.content = YUI_INIT_RE.sub( '', content) return response