templatetags: add block tag to insert blurp variables into the current context

This does not work with ajax blurp for now, you will only get
synchronous loading.

src/cmsplugin_blurp/templatetags/blurp_tags.py

@@ -7,6 +7,7 @@ from .. import utils
 
 register = template.Library()
 
+@register.tag
 class RenderBlurp(Tag):
     name = 'render_blurp'
     options = Options(
@@ -23,4 +24,18 @@ class RenderBlurp(Tag):
         if not hasattr(template, 'render'):
             template = template.Template(template)
         return template.render(context)
-register.tag(RenderBlurp)
+
+@register.tag
+class BlurpNode(Tag):
+    '''Insert content generated from a blurp block and render inside template'''
+    name = 'blurp'
+    options = Options(
+            Argument('name'),
+            blocks=[('endblurp', 'nodelist')])
+
+    def render_tag(self, context, name, nodelist):
+        context.push()
+        utils.insert_blurp_in_context(name, context)
+        output = self.nodelist.render(context)
+        context.pop()
+        return output

src/cmsplugin_blurp/utils.py

@@ -24,3 +24,9 @@ def resolve_renderer(name):
         module_name, class_name = instance['class'].rsplit('.', 1)
         module = import_module(module_name)
         return getattr(module, class_name)(name, instance)
+
+def insert_blurp_in_context(name, context):
+        renderer = resolve_renderer(name)
+        if not renderer:
+            return ''
+        return renderer.render(context)