Fix #141 and add custom event trigger binding support

analytical/context_providers/matomo.py

@@ -0,0 +1,31 @@
+import utils
+from django.conf import settings
+
+def consent_provider(request):
+    """
+    Add Mamoto consent script to the requests context.
+    """
+    # Do we require consent?
+    if getattr(settings, 'MATOMO_REQUIRE_CONSENT', False):
+        provide_script = True
+        if request.user.is_authenticated and not getattr(settings, "ALWAYS_TRACK_REGISTERED", True):
+            provide_script = False
+        if provide_script:
+            grant_class_name = getattr(settings, 'GRANT_CONSENT_TAG_CLASSNAME')
+            revoke_class_name = getattr(settings, 'REVOKE_CONSENT_CLASSNAME')
+            return {"consent_script":"""
+            %s;
+            %s
+            %s
+            """ % (
+                utils.build_paq_cmd('requireConsent'),
+                utils.get_event_bind_js(
+                    class_name=grant_class_name,
+                    matomo_event="rememberConsentGiven",
+                ),
+                utils.get_event_bind_js(
+                    class_name=revoke_class_name,
+                    matomo_event="forgetConsentGiven",
+                )
+            )}
+    return {'consent_script': ""}

analytical/templatetags/matomo.py

@@ -7,13 +7,12 @@
 from itertools import chain
 
 from django.conf import settings
-from django.template import Library, Node, TemplateSyntaxError
-
+from django.template import Library, Node, TemplateSyntaxError, Template
 from analytical.utils import (
     disable_html,
     get_identity,
     get_required_setting,
-    is_internal_ip,
+    is_internal_ip
 )
 
 # domain name (characters separated by a dot), optional port, optional URI path, no slash
@@ -48,10 +47,8 @@
 
 MatomoVar = namedtuple('MatomoVar', ('index', 'name', 'value', 'scope'))
 
-
 register = Library()
 
-
 @register.tag
 def matomo(parser, token):
     """
@@ -109,8 +106,14 @@ def render(self, context):
             'variables': '\n  '.join(variables_code),
             'commands': '\n  '.join(commands)
         }
+        # Force the consent script to render so we can inject it into the template
+        consent_script = Template("{{consent_script}}").render(context)
+        if len(consent_script) > 1:
+            html += consent_script
+
         if is_internal_ip(context, 'MATOMO'):
             html = disable_html(html, 'Matomo')
+
         return html
 
 

analytical/utils.py

@@ -1,7 +1,7 @@
 """
 Utility function for django-analytical.
 """
-
+from copy import deepcopy
 from django.conf import settings
 from django.core.exceptions import ImproperlyConfigured
 
@@ -163,3 +163,90 @@ class AnalyticalException(Exception):
     be silenced in templates.
     """
     silent_variable_failure = True
+
+def build_paq_cmd(cmd, args=[]):
+    """
+    :Args:
+        - cmd: The command to be pushed to paq (i.e enableHeartbeatTimer or contentInteraction)
+        - args: Arguments to be added to the paq command. This is mainly
+            used when building commands to be used on manual event trigger.
+
+    :Returns:
+        A complete '_paq.push([])' command in string form
+    """
+    def __to_js_arg(arg):
+        """
+        Turn 'arg' into its javascript counter-part
+        :Args:
+            - arg: the argument that's to be passed to the array in _paq.push()
+        :Return:
+            The javascript counter-part to the argument that was passed
+        """
+        if isinstance(arg, dict):
+            arg_cpy = deepcopy(arg)
+            for k, v in arg_cpy.items():
+                arg.pop(k)
+                arg[__to_js_arg(k)] = __to_js_arg(v)
+            return arg
+        elif isinstance(arg, bool):
+            if arg:
+                arg = "true"
+            else:
+                arg = "false"
+        elif isinstance(arg, list):
+            for elem_idx in range(len(arg)):
+                arg[elem_idx] = __to_js_arg(arg[elem_idx])
+
+        return arg
+
+    paq = "_paq.push(['%s'" % (cmd)
+    if len(args) > 0:
+        paq += ", "
+        for arg_idx in range(len(args)):
+            current_arg = __to_js_arg(args[arg_idx])
+            no_quotes = type(current_arg) in [bool, int, dict, list]
+            if arg_idx == len(args)-1:
+                if no_quotes:
+                    segment = "%s]);" % (current_arg)
+                else:
+                    segment = "'%s']);" % (current_arg)
+            else:
+                if no_quotes:
+                    segment = "%s, "% (current_arg)
+                else:
+                    segment = "'%s', " % (current_arg)
+            paq += segment
+    else:
+        paq += "]);"        
+    return paq
+
+def get_event_bind_js(
+    class_name, matomo_event,
+    matomo_args=[], js_event="onclick",
+    ):
+    """
+    Build a javascript command to bind an onClick event to some
+    element whose handler pushes something to _paq
+    :Args:
+        - class_name: Value of the 'class' attribute of the tag
+            the event is to be bound to.
+        - matomo_event: The matomo event to be pushed to _paq
+            such as enableHeartbeatTimer or contentInteraction
+        - matomo_args: The arguments to be passed with the matomo event
+            meaning
+    :Return:
+        A string of javascript that loops the elements found by 
+            document.getElementByClassName and binds the motomo event
+            to each element that was found
+    """
+    script = f"""
+    var elems = document.getElementByClassName('%s');
+    for (var i=0; i++; i < elems.length){{
+        elems[i].addEventListener('%s',
+            function(){{
+                %s;
+            }}
+        );
+    }}
+    """ % (class_name, js_event, build_paq_cmd(matomo_event, matomo_args))
+    return script