1 # this is the abstract interface for Plugin instances
2 # so it should be specialized in real plugin classes
3 # like e.g. plugins.simplelist.SimpleList
7 from django.template.loader import render_to_string
9 from engine.prelude import Prelude
13 # [ 'SliceList', 'TabbedView' ] : to debug these classes
14 # True : to debug all slices
16 DEBUG= [ 'SliceList' ]
20 # using a simple incremental scheme to generate uuids for now
28 def __init__ (self, visible=True, hidable=True, hidden_by_default=False, **settings):
29 # xxx should generate some random id
30 self.uuid=Plugin.newuuid()
33 self.hidden_by_default=hidden_by_default
34 # we store as a dictionary the arguments passed to constructor
35 # e.g. SimpleList (list=[1,2,3]) => _settings = { 'list':[1,2,3] }
36 # our own settings are not made part of _settings but could be..
37 self._settings=settings
39 print "Plugin.__init__ Created plugin with settings %s"%self._settings.keys()
41 # subclasses might handle some fields in their own way,
42 # in which case this call is needed to capture that setting
43 # see e.g. SimpleList or SliceList for an example of that
44 def add_to_settings (self, setting_name):
45 self._settings[setting_name]=getattr(self,setting_name)
48 try: return self.__class__.__name__
49 except: return 'Plugin'
51 # shorthands to inspect _settings
52 def get_setting (self, setting, default=None):
53 if setting not in self._settings: return default
54 else: return self._settings[setting]
56 def is_visible (self): return self.visible
57 def is_hidable (self): return self.hidable
58 def is_hidden_by_default (self): return self.hidden_by_default
61 def need_debug (self):
62 if not DEBUG: return False
63 if DEBUG is True: return True
64 else: return self.classname() in DEBUG
66 # returns the html code for that plugin
67 # in essence, wraps the results of self.render_content ()
68 def render (self, request):
70 classname = self.classname()
71 # initialize prelude placeholder
72 self._init_request (request)
75 plugin_content = self.render_content (request)
76 # expose _settings in json format to js
77 settings_json = json.dumps (self._settings, separators=(',',':'))
79 result = render_to_string ('plugin.html',
81 'classname':classname,
82 'visible':self.is_visible(),
83 'hidable':self.is_hidable(),
84 'hidden':self.is_hidden_by_default(),
85 'plugin_content' : plugin_content,
86 'settings_json' : settings_json,
89 # handle requirements() if defined on this class
91 self.handle_requirements (request, self.requirements())
92 except AttributeError:
93 # most likely the object does not have that method defined, which is fine
102 # you may redefine this completely, but if you don't we'll just use methods
103 # . template_file() to find out which template to use, and
104 # . template_env() to compute a dictionary to pass along to the templating system
105 def render_content (self, request):
106 """Should return an HTML fragment"""
107 template = self.template_file()
108 env=self.template_env(request)
109 if not isinstance (env,dict):
110 raise Exception, "%s.template_env returns wrong type"%self.classname()
111 # expose this class's settings to the template
112 # xxx we might need to check that this does not overwrite env..
113 env.update(self._settings)
114 result=render_to_string (template, env)
115 if self.need_debug():
116 print "%s.render_content: BEG --------------------"%self.classname()
117 print "template=%s"%template
118 print "env=%s"%env.keys()
120 print "%s.render_content: END --------------------"%self.classname()
123 #################### requirements/prelude management
124 def _init_request (self, request):
125 if not hasattr (request, 'plugin_prelude'):
126 # include css/plugins.css
127 request.plugin_prelude=Prelude(css_files='css/plugin.css')
129 def inspect_request (self, request, message):
130 has=hasattr(request,'plugin_prelude')
131 get=getattr(request,'plugin_prelude','none-defined')
132 print "INSPECT (%s), hasattr %s, getattr %s"%(message,has,get)
134 # can be used directly in render_content()
135 def add_js_files (self, request, files):
136 self._init_request (request)
137 request.plugin_prelude.add_js_files (files)
138 def add_css_files (self, request, files):
139 self._init_request (request)
140 request.plugin_prelude.add_css_files (files)
141 def add_js_chunks (self, request, chunks):
142 self._init_request (request)
143 request.plugin_prelude.add_js_chunks (chunks)
144 def add_css_chunks (self, request, chunks):
145 self._init_request (request)
146 request.plugin_prelude.add_css_chunks (chunks)
148 # or from the result of self.requirements()
149 def handle_requirements (self, request, d):
150 for (k,v) in d.iteritems():
151 if self.need_debug():
152 print "%s: handling requirement %s"%(self.classname(),v)
154 method=Plugin.__dict__[method_name]
155 method(self,request,v)
157 ######################################## abstract interface
158 def title (self): return "you should redefine title()"
160 # your plugin is expected to implement either
161 # (*) def render_content(self, request) -> html fragment
163 # (*) def template_file(self) -> filename
165 # (*) def template_env (self, request) -> dict
166 # this is the variable->value association used to render the template
167 # in which case the html template will be used
169 # if you see this string somewhere your template_file() code is not kicking in
170 def template_file (self): return "undefined_template"
171 def template_env (self, request): return {}
173 # # tell the framework about requirements (for the document <header>)
174 # # the notion of 'Media' in django provides for medium-dependant
175 # # selection of css files
176 # # as a first attempt however we keep a flat model for now
177 # # can use one string instead of a list or tuple if needed,
178 # # see requirements.py for details
179 # def requirements (self):
180 # return { 'js_files' : [], # a list of relative paths for js input files
181 # 'css_files': [], # ditto for css, could have been a dict keyed on
183 # 'js_chunk' : [], # (lines of) verbatim javascript code
184 # 'css_chunk': [], # likewise for css scripts