From bb3f0d3cff573fe20df41b715b787e77d6bc9b40 Mon Sep 17 00:00:00 2001
From: Jasper Van der Jeugt <m@jaspervdj.be>
Date: Wed, 30 Mar 2016 21:32:12 +0200
Subject: [PATCH] Add external articles

---
 web/site.hs                                   | 57 +++++++++++--------
 web/templates/tutorial-item.html              |  1 -
 web/templates/tutorials.html                  | 36 +++++++++++-
 .../external-clean-urls-with-hakyll.md        |  6 ++
 4 files changed, 74 insertions(+), 26 deletions(-)
 delete mode 100644 web/templates/tutorial-item.html
 create mode 100644 web/tutorials/external-clean-urls-with-hakyll.md

diff --git a/web/site.hs b/web/site.hs
index a1c2a49..bf84f1e 100644
--- a/web/site.hs
+++ b/web/site.hs
@@ -1,14 +1,13 @@
 --------------------------------------------------------------------------------
 {-# LANGUAGE OverloadedStrings #-}
-import           Control.Applicative ((<$>))
-import           Control.Arrow       (second)
-import           Control.Monad       (forM_)
-import           Data.Char           (isDigit)
-import           Data.List           (isPrefixOf, partition, sortBy)
-import           Data.Monoid         (mappend)
-import           Data.Ord            (comparing)
+import           Control.Arrow   (second)
+import           Control.Monad   (forM_)
+import           Data.Char       (isDigit)
+import           Data.List       (isPrefixOf, sortBy)
+import           Data.Monoid     ((<>))
+import           Data.Ord        (comparing)
 import           Hakyll
-import           System.FilePath     (dropTrailingPathSeparator, splitPath)
+import           System.FilePath (dropTrailingPathSeparator, splitPath)
 import           Text.Pandoc
 
 
@@ -53,18 +52,12 @@ main = hakyllWith config $ do
     create ["tutorials.html"] $ do
         route idRoute
         compile $ do
-            tutorials <- loadAll "tutorials/*"
-            itemTpl   <- loadBody "templates/tutorial-item.html"
-            let (series, articles) = partitionTutorials $
-                    sortBy (comparing itemIdentifier) tutorials
-
-            series'   <- applyTemplateList itemTpl defaultContext series
-            articles' <- applyTemplateList itemTpl defaultContext articles
+            tuts <-
+                sortBy (comparing itemIdentifier) <$> loadAll "tutorials/*"
 
             let tutorialsCtx =
                     constField "title" "Tutorials"  `mappend`
-                    constField "series" series'     `mappend`
-                    constField "articles" articles' `mappend`
+                    listField "tutorials"   tutorialCtx (return tuts) `mappend`
                     defaultContext
 
             makeItem ""
@@ -112,9 +105,27 @@ hackage url
 
 
 --------------------------------------------------------------------------------
--- | Partition tutorials into tutorial series & other articles
-partitionTutorials :: [Item a] -> ([Item a], [Item a])
-partitionTutorials = partition $ \i ->
-    case splitPath (toFilePath $ itemIdentifier i) of
-        [_, (x : _)] -> isDigit x
-        _            -> False
+data TutorialType = SeriesTutorial | ArticlesTutorial | ExternalTutorial
+    deriving (Eq)
+
+
+--------------------------------------------------------------------------------
+-- | Partition tutorials into tutorial series, other articles, external articles
+tutorialCtx :: Context String
+tutorialCtx =
+    field "isSeries"   (isTutorialType SeriesTutorial)   <>
+    field "isArticle"  (isTutorialType ArticlesTutorial) <>
+    field "isExternal" (isTutorialType ExternalTutorial) <>
+    defaultContext
+  where
+    getTutorialType item = do
+        mbExternal <- getMetadataField (itemIdentifier item) "external"
+        return $ case mbExternal of
+            Just _ -> ExternalTutorial
+            _      -> case splitPath (toFilePath $ itemIdentifier item) of
+                [_, (x : _)] -> if isDigit x then SeriesTutorial else ArticlesTutorial
+                _            -> ArticlesTutorial
+
+    isTutorialType ty0 item = do
+        ty1 <- getTutorialType item
+        if ty0 == ty1 then return "yes" else fail "no"
diff --git a/web/templates/tutorial-item.html b/web/templates/tutorial-item.html
deleted file mode 100644
index e0d7866..0000000
--- a/web/templates/tutorial-item.html
+++ /dev/null
@@ -1 +0,0 @@
-<li><a href="$url$">$title$</a> by <em>$author$</em></li>
diff --git a/web/templates/tutorials.html b/web/templates/tutorials.html
index 36c808c..6bd8351 100644
--- a/web/templates/tutorials.html
+++ b/web/templates/tutorials.html
@@ -1,9 +1,36 @@
 <h1>Tutorials about Hakyll</h1>
 <h2>Tutorial series</h2>
-<ul>$series$</ul>
+<ul>
+    $for(tutorials)$
+        $if(isSeries)$
+            <li>
+                <a href="$url$">$title$</a>
+            </li>
+        $endif$
+    $endfor$
+</ul>
 <h2>Other articles</h2>
 <p>In no particular order:</p>
-<ul>$articles$</ul>
+<ul>
+    $for(tutorials)$
+        $if(isArticle)$
+            <li>
+                <a href="$url$">$title$</a> by <em>$author$</em>
+            </li>
+        $endif$
+    $endfor$
+</ul>
+<h2>External articles</h2>
+<p>In no particular order:</p>
+<ul>
+    $for(tutorials)$
+        $if(isExternal)$
+            <li>
+                <a href="$url$">$title$</a> by <em>$author$</em>
+            </li>
+        $endif$
+    $endfor$
+</ul>
 <p>
     All these tutorials assume you are using the latest stable version of
     Hakyll. If this is not the case, you might want to update using:
@@ -11,3 +38,8 @@
 <pre><code>$$ ghc-pkg unregister hakyll
 $$ cabal update
 $$ cabal install hakyll</code></pre>
+
+<p>
+    Or using stack:
+</p>
+<pre><code>$$ stack install hakyll</code></pre>
diff --git a/web/tutorials/external-clean-urls-with-hakyll.md b/web/tutorials/external-clean-urls-with-hakyll.md
new file mode 100644
index 0000000..127a192
--- /dev/null
+++ b/web/tutorials/external-clean-urls-with-hakyll.md
@@ -0,0 +1,6 @@
+---
+title: Clean URLs with Hakyll
+author: Rohan Jain
+url: http://www.rohanjain.in/hakyll-clean-urls/
+external: true
+---