# this is the abstract interface for Plugin instances # so it should be specialized in real plugin classes # like e.g. plugins.simplelist.SimpleList import json from django.template.loader import render_to_string from engine.pluginset import PluginSet from engine.prelude import Prelude #################### # set DEBUG to # . False : silent # . [ 'SliceList', 'TabbedView' ] : to debug these classes # . True : to debug all plugin DEBUG= False #DEBUG= [ 'SimpleList' ] # decorator to deflect calls on Plugin to its PluginSet def to_prelude (method): def actual (self, *args, **kwds): prelude_method=Prelude.__dict__[method.__name__] return prelude_method(self.pluginset.prelude,*args, **kwds) return actual class Plugin: # using a simple incremental scheme to generate domids for now # we just need this to be unique in a page domid=0 @staticmethod def newdomid(): Plugin.domid += 1 return "plugin-%d"%Plugin.domid ########## # Constructor #### mandatory # . pluginset: the context of the request being served # . title: is used visually for displaying the widget #### optional # . togglable: whether it can be turned on and off (like PleKitToggle) # . toggled: if togglable, what's the initial status # . visible: if not set the plugin does not show up at all # (not quite sure what this was for) #### internal data # . domid: created internally, but can be set at creation time if needed # useful for hand-made css, or for selecting an active plugin in a composite # . rank: this is for plugins sons of a composite plugin #### custom # any other setting can also be set when creating the object, like # p=Plugin(foo='bar') # which will result in 'foo' being accessible to the template engine # def __init__ (self, pluginset, title, domid=None, visible=True, togglable=True, toggled=True, **settings): self.pluginset = pluginset self.title=title if not domid: domid=Plugin.newdomid() self.domid=domid self.classname=self._classname() self.visible=visible self.togglable=togglable self.toggled=toggled # what comes from subclasses for (k,v) in settings.iteritems(): setattr(self,k,v) if self.need_debug(): print "%s init - subclass setting %s"%(self.classname,k) # minimal debugging if self.need_debug(): print "%s init dbg .... BEG"%self.classname for (k,v) in self.__dict__.items(): print "dbg %s:%s"%(k,v) print "%s init dbg .... END"%self.classname # do this only once the structure is fine self.pluginset.record_plugin(self) def _classname (self): try: return self.__class__.__name__ except: return 'Plugin' ########## def need_debug (self): if not DEBUG: return False if DEBUG is True: return True else: return self.classname in DEBUG def setting_json (self, setting): # TMP: js world expects plugin_uuid if setting=='plugin_uuid': value=self.domid elif setting=='query_uuid': try: value=self.query.uuid except: return '%s:"undefined"'%setting else: value=getattr(self,setting,None) if not value: value = "unknown-setting-%s"%setting # first try to use to_json method (json.dumps not working on class instances) try: value_json=value.to_json() except: value_json=json.dumps(value,separators=(',',':')) return "%s:%s"%(setting,value_json) # expose in json format to js the list of fields as described in json_settings_list() # and add plugin_uuid: domid in the mix # NOTE this plugin_uuid thing might occur in js files from joomla/js, ** do not rename ** def settings_json (self): result = "{" result += ",".join([ self.setting_json(setting) for setting in self.json_settings_list() ]) result += "}" return result # returns the html code for that plugin # in essence, wraps the results of self.render_content () def render (self, request): # call render_content plugin_content = self.render_content (request) # shove this into plugin.html env = {} env ['plugin_content']= plugin_content env.update(self.__dict__) result = render_to_string ('plugin.html',env) # as a first approximation we're only concerned with plugins that are associated with a query # other simpler plugins that only deal with layout do not need this if 'query' in self.__dict__: env ['settings_json' ] = self.settings_json() # compute plugin-specific initialization js_init = render_to_string ( 'plugin-setenv.js', env ) self.add_js_chunks (js_init) # interpret the result of requirements () self.handle_requirements (request) return result # you may redefine this completely, but if you don't we'll just use methods # . template_file() to find out which template to use, and # . template_env() to compute a dictionary to pass along to the templating system def render_content (self, request): """Should return an HTML fragment""" template = self.template_file() env=self.template_env(request) if not isinstance (env,dict): raise Exception, "%s.template_env returns wrong type"%self.classname result=render_to_string (template, env) if self.need_debug(): print "%s.render_content: BEG --------------------"%self.classname print "template=%s"%template print "env.keys=%s"%env.keys() #print "env=%s"%env #print result print "%s.render_content: END --------------------"%self.classname return result # or from the result of self.requirements() def handle_requirements (self, request): try: d=self.requirements() for (k,v) in d.iteritems(): if self.need_debug(): print "%s: handling requirement %s"%(self.classname,v) method_name='add_'+k method=PluginSet.__dict__[method_name] method(self.pluginset,v) except AttributeError: # most likely the object does not have that method defined, which is fine pass except: import traceback traceback.print_exc() pass #################### requirements/prelude management # just forward to self.pluginset - see decorator above @to_prelude def add_js_files (self):pass @to_prelude def add_css_files (self):pass @to_prelude def add_js_chunks (self):pass @to_prelude def add_css_chunks (self):pass ######################################## abstract interface # your plugin is expected to implement either # (*) def render_content(self, request) -> html fragment # -- or -- # (*) def template_file (self) -> filename # relative to STATIC # (*) def template_env (self, request) -> dict # this is the variable->value association used to render the template # in which case the html template will be used # if you see this string somewhere your template_file() code is not kicking in def template_file (self): return "undefined_template" def template_env (self, request): return {} # # tell the framework about requirements (for the document
) # # the notion of 'Media' in django provides for medium-dependant # # selection of css files # # as a first attempt however we keep a flat model for now # # can use one string instead of a list or tuple if needed, # # see requirements.py for details # def requirements (self): # return { 'js_files' : [], # a list of relative paths for js input files # 'css_files': [], # ditto for css, could have been a dict keyed on # # media instead # 'js_chunk' : [], # (lines of) verbatim javascript code # 'css_chunk': [], # likewise for css scripts # } # # for better performance # # you can specify a list of keys that won't be exposed as json attributes # def exclude_from_json (self): return [] # mandatory : define the fields that need to be exposed to json as part of # plugin initialization # mention 'domid' if you need plugin_uuid # also 'query_uuid' gets replaced with query.uuid def json_settings_list (self): return ['json_settings_list-must-be-redefined']