Add hooks to add css/javascript

(specific for some pages using web.ctx)
Fixes #43

doc/dev_doc/hook_guide.rst

@@ -12,19 +12,38 @@ List of hooks
 -------------
 
 Each hook available in INGInious is described here, starting with its name and parameters.
+*css*
+    Used to add CSS files in the header. 
+    Should return the path to a CSS file (relative to the root of INGInious).
+*course_admin_menu* (*course*)
+    Used to add links to the administration menu. This hook should return a tuple (link,name) 
+    where link is the relative link from the index of the course administration.
+    You can also return None.
+*course_menu* (*course*)
+    Allows to add HTML to the menu displayed on the course page. Course is the course object related to the page.
+    Should return HTML or None.
+*javascript_header*
+    Used to add Javascript files in the header. 
+    Should return the path to a Javascript file (relative to the root of INGInious).
+*javascript_footer*
+    Used to add Javascript files in the footer. 
+    Should return the path to a Javascript file (relative to the root of INGInious).
+*job_ended* (*jobid*, *task*, *statinfo*, *results*)
+   Called when a job has ended. *task* contains a Task object,
+   *statinfo* is a dictionnary containing various informations about the job.
+   *results* contains the results of the job.
 *job_manager_init_done* (*job_manager*)
 	Called when a JobManager instance is inited. *job_manager* is the instance that was inited.
 	This hooks cannot be used by the plugins, as the backend is inited before the plugins.
 *job_manager_exit* (*job_manager*)
 	Called when a JobManager received the exit signal, before the JobManager exits.
+*modify_task_data* (*course*, *taskid*, *data*)
+    Allows to modify the task description before the initialisation of the Task object.
+    Changes are not saved to disk.
 *new_job* (*jobid*, *task*, *statinfo*, *inputdata*)
 	Called when a job was just submitted. *task* contains a Task object,
 	*statinfo* is a dictionnary containing various informations about the job.
 	*inputdata* contains the answers that were submitted to INGInious.
-*job_ended* (*jobid*, *task*, *statinfo*, *results*)
-	Called when a job has ended. *task* contains a Task object,
-	*statinfo* is a dictionnary containing various informations about the job.
-	*results* contains the results of the job.
 *new_submission* (*submissionid*, *submission*, *jobid*, *inputdata*)
 	Called when a new submission is received.
 	*inputdata* contains the answers that were submitted to INGInious.
@@ -36,14 +55,4 @@ Each hook available in INGInious is described here, starting with its name and p
 	(submission_done is called after job_ended)
 *template_helper* ()
     Adds a new helper to the instance of TemplateHelper. Should return a tuple (name,func) where name is the name that will
-    be indicated when calling the TemplateHelper.call method, and func is the function that will be called.
-*course_admin_menu* (*course*)
-    Used to add links to the administration menu. This hook should return a tuple (link,name) 
-    where link is the relative link from the index of the course administration.
-    You can also return None.
-*modify_task_data* (*course*, *taskid*, *data*)
-    Allows to modify the task description before the initialisation of the Task object.
-    Changes are not saved to disk.
-*course_menu* (*course*)
-    Allows to add HTML to the menu displayed on the course page. Course is the course object related to the page.
-    Should return HTML or None.
+    be indicated when calling the TemplateHelper.call method, and func is the function that will be called.

frontend/template_helper.py

@@ -18,6 +18,8 @@
 # License along with INGInious.  If not, see <http://www.gnu.org/licenses/>.
 """ Helper for the templates """
 
+import web
+
 from frontend.base import add_to_template_globals
 import frontend.pages.course_admin.utils
 from frontend.plugins.plugin_manager import PluginManager
@@ -36,7 +38,11 @@ class TemplateHelper(object):
     _instance = None
     _base_helpers = {"header_hook": (lambda **kwargs: generic_hook('header_html', **kwargs)),
                      "course_menu": (lambda **kwargs: generic_hook('course_menu', **kwargs)),
+                     "javascript_header": (lambda **_: TemplateHelper._javascript_helper("header")),
+                     "javascript_footer": (lambda **_: TemplateHelper._javascript_helper("footer")),
+                     "css": (lambda **_: TemplateHelper._css_helper()),
                      "course_admin_menu": frontend.pages.course_admin.utils.get_menu}
+    WEB_CTX_KEY = "inginious_tpl_helper"
 
     def __new__(cls, *args, **kwargs):
         if not cls._instance:
@@ -58,3 +64,44 @@ def call(self, name, **kwargs):
             return ""
         else:
             return helpers.get(name, None)(**kwargs)
+
+    def add_javascript(self, link, position="footer"):
+        """ Add a javascript file to load. Position can either be "header" or "footer" """
+        self._get_ctx()["javascript"][position].append(link)
+
+    def add_css(self, link):
+        """ Add a css file to load """
+        self._get_ctx()["css"].append(link)
+
+    @classmethod
+    def _javascript_helper(cls, position):
+        """ Add javascript links for the current page and for the plugins """
+        if position not in ["header", "footer"]:
+            position = "footer"
+
+        # Load javascript files from plugins
+        if position == "header":
+            entries = [entry for entry in PluginManager.get_instance().call_hook("javascript_header") if entry is not None]
+        else:
+            entries = [entry for entry in PluginManager.get_instance().call_hook("javascript_footer") if entry is not None]
+        # Load javascript for the current page
+        entries += cls.get_instance()._get_ctx()["javascript"][position]
+        entries = ["<script src='" + entry + "' type='text/javascript' charset='utf-8'></script>" for entry in entries]
+        return "\n".join(entries)
+
+    @classmethod
+    def _css_helper(cls):
+        """ Add CSS links for the current page and for the plugins """
+        entries = [entry for entry in PluginManager.get_instance().call_hook("css") if entry is not None]
+        # Load javascript for the current page
+        entries += cls.get_instance()._get_ctx()["css"]
+        entries = ["<link href='" + entry + "' rel='stylesheet'>" for entry in entries]
+        return "\n".join(entries)
+
+    def _get_ctx(self):
+        """ Get web.ctx object for the Template helper """
+        if self.WEB_CTX_KEY not in web.ctx:
+            web.ctx[self.WEB_CTX_KEY] = {
+                "javascript": {"footer": [], "header": []},
+                "css": []}
+        return web.ctx.get(self.WEB_CTX_KEY)

templates/layout.html

@@ -60,7 +60,9 @@
 
 $if "header" in content:
     $:content.header
-
+
+$:template_helper.call('css')
+$:template_helper.call('javascript_header')
 $:template_helper.call('header_hook')
 </head>
 
@@ -124,5 +126,6 @@
     <script type="text/javascript" src="//cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
     <script type="text/javascript" src="https://www.google.com/jsapi"></script>
     <script type="text/javascript">google.load('visualization', '1.0', {'packages':['corechart']});</script>
+    $:template_helper.call('javascript_footer')
 </body>
 </html>