add post summaries

blog-meta/post-lists.hs

@@ -8,7 +8,7 @@ import qualified Data.Text as Text
 import Data.Time
 import Misc
 import qualified YAML
-import YAML ((.:), (.!=), (##=))
+import YAML ((.:), (.:?), (.!=), (##=))
 import qualified System.Console.GetOpt as GetOpt
 import qualified System.FilePath.Find as Find
 import qualified System.FilePath as Path
@@ -69,27 +69,30 @@ getInfo dir file = do
   let dirs = Path.splitPath dir
   let file' = Path.joinPath $ drop (length dirs) $ Path.splitPath file
   unwrap file $ YAML.parseEither $
-    yaml & YAML.withMap "title, date, tags" \m ->
+    yaml & YAML.withMap "title, date, tags, summary?" \m ->
       Info <$> pure file'
-           <*> m .: "title"
-           <*> m .: "date"
-           <*> m .: "tags" .!= []
+           <*> m .:  "title"
+           <*> m .:  "date"
+           <*> m .:  "tags" .!= []
+           <*> m .:? "summary"
 
 -- | the front matter info we care about
 data PostInfo =
   Info {
-    _nfoFile  :: FilePath,
-    _nfoTitle :: Text,
+    infoFile  :: FilePath,
+    infoTitle :: Text,
     infoDate  :: BlogDate,
-    infoTags  :: [Text]
+    infoTags  :: [Text],
+    infoSummary :: Maybe Text
   }
 
 instance YAML.ToYAML PostInfo where
-  toYAML (Info file title date tags) = YAML.obj
-    [("date"  ##= date),
-     ("title" ##= title),
-     ("tags"  ##= tags),
-     ("file"  ##= Text.pack (fixup file))]
+  toYAML (Info file title date tags summary) = YAML.obj
+    [("date"     ##= date),
+     ("title"    ##= title),
+     ("tags"     ##= tags),
+     ("file"     ##= Text.pack (fixup file)),
+     ("summary"  ##= summary)]
     where fixup f = Path.replaceExtension f "html"
 
 newtype BlogDate = D Day deriving (Eq, Ord)