Initial implementation of l10n block type with jingo-like render shortcut.

apps/l10n_example/templates/l10n_example/example.html

@@ -0,0 +1,15 @@
+{% extends "base.html" %}
+
+{% block content %}
+  <h1>Hello world!</h1>
+
+  {% l10n foo %}
+  <p>Localizable, unversioned.</p>
+  {% endl10n %}
+
+  {% l10n bar, 3 %}
+  <p>Localizable, versioned.</p>
+  {% endl10n %}
+
+  <p>unlocalizable.</p>
+{% endblock %}

apps/l10n_example/urls.py

@@ -0,0 +1,8 @@
+from django.conf.urls.defaults import patterns
+
+import jingo
+
+
+urlpatterns = patterns('',
+    (r'^$', 'l10n_example.views.example'),
+)

apps/l10n_example/views.py

@@ -0,0 +1,5 @@
+import l10n_utils
+
+
+def example(request):
+    return l10n_utils.render(request, 'l10n_example/example.html')

lib/l10n_utils/__init__.py

@@ -0,0 +1,29 @@
+from django.conf import settings
+
+import jingo
+from jinja2.exceptions import TemplateNotFound
+
+
+def render(request, template, context=None, **kwargs):
+    """
+    Same as jingo's render() shortcut, but with l10n template support.
+    If used like this::
+
+        return l10n_utils.render(request, 'myapp/mytemplate.html')
+
+    ... this helper will render the following template::
+
+        l10n/LANG/myapp/mytemplate.html
+
+    if present, otherwise, it'll render the specified (en-US) template.
+    """
+    # Look for localized template if not default lang.
+    if request.locale != settings.LANGUAGE_CODE:
+        localized_tmpl = 'l10n/%s/%s' % (request.locale, template)
+        try:
+            return jingo.render(request, localized_tmpl, context, **kwargs)
+        except TemplateNotFound:
+            # If not found, just go on and try rendering the parent template.
+            pass
+
+    return jingo.render(request, template, context, **kwargs)

lib/l10n_utils/template.py

@@ -0,0 +1,47 @@
+"""
+A Jinja extension adding support for localizable template blocks.
+"""
+
+from jinja2.ext import Environment, Extension, nodes
+
+
+class L10nBlockExtension(Extension):
+    """
+    Add support for an L10n block that works like a regular "block" for now.
+    """
+
+    tags = set(['l10n'])
+
+    def parse(self, parser):
+        # Jump over first token ("l10n"), grab line number.
+        lineno = parser.stream.next().lineno
+
+        # Block name is mandatory.
+        name = parser.stream.expect('name').value
+
+        # Comma optional.
+        parser.stream.skip_if('comma')
+
+        # Add version if provided.
+        if parser.stream.current.type == 'integer':
+            version = int(parser.parse_expression().value)
+        else:
+            version = 0  # Default version for unversioned block.
+
+        # Parse content, drop closing tag.
+        body = parser.parse_statements(['name:endl10n'], drop_needle=True)
+
+        # Build regular block node with special node name and remember version.
+        node = nodes.Block()
+        node.set_lineno(lineno)
+        node.name = '__l10n__{0}'.format(name)
+        node.version = version  # For debugging only, for now.
+        node.body = body
+        # I *think*, `true` would mean that variable assignments inside this
+        # block do not persist beyond this block (like a `with` block).
+        node.scoped = False
+
+        return node
+
+# Makes for a prettier import in settings.py
+l10n_blocks = L10nBlockExtension

settings.py

@@ -50,7 +50,7 @@ TEXT_DOMAIN = 'messages'
 LANGUAGE_CODE = 'en-US'
 
 # Accepted locales
-KNOWN_LANGUAGES = ('en-US',)
+KNOWN_LANGUAGES = ('de', 'en-US', 'es', 'fr',)
 
 # List of RTL locales known to this project. Subset of LANGUAGES.
 RTL_LANGUAGES = ()  # ('ar', 'fa', 'fa-IR', 'he')
@@ -120,7 +120,8 @@ def JINJA_CONFIG():
     from django.conf import settings
 #    from caching.base import cache
     config = {'extensions': ['tower.template.i18n', 'jinja2.ext.do',
-                             'jinja2.ext.with_', 'jinja2.ext.loopcontrols'],
+                             'jinja2.ext.with_', 'jinja2.ext.loopcontrols',
+                             'l10n_utils.template.l10n_blocks'],
               'finalize': lambda x: x if x is not None else ''}
 #    if 'memcached' in cache.scheme and not settings.DEBUG:
         # We're passing the _cache object directly to jinja because
@@ -172,6 +173,7 @@ INSTALLED_APPS = (
     # Local apps
     'commons',  # Content common to most playdoh-based apps.
     'careers',
+    'l10n_example',  # DELETEME
 
     # We need this so the jsi18n view will pick up our locale directory.
     ROOT_PACKAGE,
@@ -198,6 +200,7 @@ INSTALLED_APPS = (
 
     # L10n
     'product_details',
+    'l10n_utils',
 )
 
 # Tells the extract script what files to look for L10n in and what function

templates/l10n/de/l10n_example/example.html

@@ -0,0 +1,11 @@
+{% extends "l10n_example/example.html" %}
+
+{#
+{% l10n foo %}
+<p>Foo, overwritten.</p>
+{% endl10n %}
+#}
+
+{% l10n bar, 2 %}
+<p>Dies ist deutsch: Bar, overwritten but v2.</p>
+{% endl10n %}

templates/l10n/fr/l10n_example/example.html

@@ -0,0 +1,5 @@
+{% extends "l10n_example/example.html" %}
+
+{% l10n foo %}
+<p>C'est français: Foo, overwritten.</p>
+{% endl10n %}

urls.py

@@ -1,6 +1,7 @@
 from django.conf import settings
 from django.conf.urls.defaults import *
 
+
 # Uncomment the next two lines to enable the admin:
 # from django.contrib import admin
 # admin.autodiscover()
@@ -8,6 +9,9 @@ from django.conf.urls.defaults import *
 urlpatterns = patterns('',
     (r'', include('careers.urls')),
 
+    # L10n example.
+    (r'^l10n_example/', include('l10n_example.urls')),
+
 
     # Uncomment the admin/doc line below to enable admin documentation:
     # (r'^admin/doc/', include('django.contrib.admindocs.urls')),