Checkpoint. Not 100% test coverage.

1 files changed, 82 insertions, 0 deletions

diff --git a/repoze/bfg/renderers.py b/repoze/bfg/renderers.py
new file mode 100644
index 000000000..495a35541
--- /dev/null
+++ b/repoze/bfg/renderers.py
@@ -0,0 +1,82 @@
+import os
+import pkg_resources
+
+from zope.component import queryUtility
+from zope.component import getSiteManager
+
+from repoze.bfg.path import caller_package
+from repoze.bfg.settings import get_settings
+
+from repoze.bfg.interfaces import IRendererFactory
+from repoze.bfg.interfaces import ITemplateRenderer
+
+try:
+    import json
+except ImportError:
+    import simplejson as json
+
+# concrete renderer factory implementations
+
+def json_renderer_factory(name):
+    def _render(value):
+        return json.dumps(value)
+    return _render
+
+# utility functions
+
+def template_renderer_factory(path, impl, level=3):
+    if os.path.isabs(path):
+        # 'path' is an absolute filename (not common and largely only
+        # for backwards compatibility)
+        if not os.path.exists(path):
+            raise ValueError('Missing template file: %s' % path)
+        renderer = queryUtility(ITemplateRenderer, name=path)
+        if renderer is None:
+            renderer = impl(path)
+            sm = getSiteManager()
+            sm.registerUtility(renderer, ITemplateRenderer, name=path)
+
+    else:
+        # 'path' is a relative filename or a package:relpath spec
+        if ':' in path:
+            # it's a package:relpath spec
+            spec = path.split(':', 1)
+            utility_name = path
+        else:
+            # it's a relpath only
+            package = caller_package(level=level)
+            spec = (package.__name__, path) 
+            utility_name = '%s:%s' % spec # utility name must be a string
+        renderer = queryUtility(ITemplateRenderer, name=utility_name)
+        if renderer is None:
+            # service unit tests here by trying the relative path
+            # string as the utility name directly
+            renderer = queryUtility(ITemplateRenderer, name=path)
+        if renderer is None:
+            if not pkg_resources.resource_exists(*spec):
+                raise ValueError('Missing template resource: %s' % utility_name)
+            abspath = pkg_resources.resource_filename(*spec)
+            renderer = impl(abspath)
+            if not _reload_resources():
+                # cache the template
+                sm = getSiteManager()
+                sm.registerUtility(renderer, ITemplateRenderer,
+                                   name=utility_name)
+        
+    return renderer
+
+def renderer_from_name(path, level=4):
+    name = os.path.splitext(path)[1]
+    if not name:
+        name = path
+    factory = queryUtility(IRendererFactory, name=name)
+    if factory is None:
+        raise ValueError('No renderer for renderer name %r' % name)
+    return factory(path)
+
+def _reload_resources():
+    settings = get_settings()
+    if settings:
+        return settings['reload_resources']
+    return False
+