metadata format helper

getnikola · Jun 5, 2017 · f743443 · f743443
1 parent 61b50a1
commit f743443
Showing 1 changed file with 30 additions and 1 deletion.
diff --git a/nikola/plugin_categories.py b/nikola/plugin_categories.py
@@ -34,8 +34,16 @@
 
 from yapsy.IPlugin import IPlugin
 from doit.cmd_base import Command as DoitCommand
+try:
+    import toml
+except ImportError:
+    toml = None
+try:
+    import yaml
+except ImportError:
+    yaml = None
 
-from .utils import LOGGER, first_line
+from .utils import LOGGER, first_line, req_missing
 
 __all__ = (
     'Command',
@@ -320,6 +328,27 @@ def compile_html(self, source, dest, is_two_file=True):
         """Compile the source, save it on dest (DEPRECATED)."""
         raise NotImplementedError()
 
+    def format_metadata(self, metadata, format='nikola'):
+        """Return a string with metadata formatted according to preferences."""
+        format = self.site.config.get('METADATA_FORMAT', format).lower()
+
+        if format not in ['nikola', 'yaml', 'toml']:
+            LOGGER.warn('Unknown METADATA_FORMAT %s', format)
+
+        if format == 'yaml':
+            if yaml is None:
+                req_missing('pyyaml', 'use YAML metadata', optional=False)
+                return '\n'.join(('---', yaml.dump(metadata), '---'))
+        elif format == 'toml':
+            if toml is None:
+                req_missing('toml', 'use TOML metadata', optional=False)
+                return '\n'.join(('+++', toml.dumps(metadata), '+++'))
+        else:  # Nikola
+            results = []
+            for k, v in metadata.items:
+                results.append('.. {k}: {v}'.format(k=k, v=v))
+            return '\n'.join(results)
+
     def create_post(self, path, content=None, onefile=False, is_page=False, **kw):
         """Create post file with optional metadata."""
         raise NotImplementedError()