Open Graph Protocol metadata for version pages

iiska · iiska · commit f61093739e8f · 2018-10-17T20:11:12.000+03:00
Renders OGP metadata for package documentation pages which could be used to enable prettier rendering of Elm package links when shared at social sites, chat rooms and forums. For example `elm/http` would have following metadata section: ```html <meta property="og:site_name" content="Elm Packages"> <meta property="og:title" content="http 1.0.0"> <meta property="og:image" content="https://package.elm-lang.org/assets/elm_logo.svg"> <meta property="og:description" content="Make HTTP requests"> ``` Could resolve #236.
diff --git a/assets/elm_logo.svg b/assets/elm_logo.svg
@@ -0,0 +1,39 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Generator: Adobe Illustrator 17.1.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
+   viewBox="0 0 323.141 322.95" enable-background="new 0 0 323.141 322.95" xml:space="preserve">
+<g>
+  <polygon
+    fill="#F0AD00"
+    points="161.649,152.782 231.514,82.916 91.783,82.916"/>
+
+  <polygon
+    fill="#7FD13B"
+    points="8.867,0 79.241,70.375 232.213,70.375 161.838,0"/>
+
+  <rect
+    fill="#7FD13B"
+    x="192.99"
+    y="107.392"
+    transform="matrix(0.7071 0.7071 -0.7071 0.7071 186.4727 -127.2386)"
+    width="107.676"
+    height="108.167"/>
+
+  <polygon
+    fill="#60B5CC"
+    points="323.298,143.724 323.298,0 179.573,0"/>
+
+  <polygon
+    fill="#5A6378"
+    points="152.781,161.649 0,8.868 0,314.432"/>
+
+  <polygon
+    fill="#F0AD00"
+    points="255.522,246.655 323.298,314.432 323.298,178.879"/>
+
+  <polygon
+    fill="#60B5CC"
+    points="161.649,170.517 8.869,323.298 314.43,323.298"/>
+</g>
+</svg>
diff --git a/src/backend/Main.hs b/src/backend/Main.hs
@@ -187,15 +187,16 @@ serveVersion memory author project maybeVersion info =
         Nothing ->
           S.pass
 
-        Just (Memory.Summary versions _ _) ->
+        Just (Memory.Summary versions maybeDetails _) ->
           case verifyVersion maybeVersion versions of
             Nothing ->
               S.pass
 
             Just version ->
               case info of
                 Readme ->
-                  ServeFile.version name version Nothing
+                  ServeFile.version name version Nothing $
+                    maybe Nothing (Just . fst) maybeDetails
 
                 Module asset ->
                   serveVersionHelp name version asset
@@ -220,7 +221,7 @@ serveVersionHelp name version asset =
     _ ->
       case Module.fromHyphenPath asset of
         Just moduleName ->
-          ServeFile.version name version (Just moduleName)
+          ServeFile.version name version (Just moduleName) Nothing
 
         Nothing ->
           S.pass
diff --git a/src/backend/ServeFile.hs b/src/backend/ServeFile.hs
@@ -28,7 +28,7 @@ import qualified Elm.Package as Pkg
 
 misc :: B.Builder -> Snap ()
 misc title =
-  makeHtml title mempty
+  makeHtml title mempty (makeOgpMetadata title Nothing)
 
 
 
@@ -37,15 +37,18 @@ misc title =
 
 project :: Pkg.Name -> Snap ()
 project pkg =
-  makeHtml (B.stringUtf8 (Pkg.toString pkg)) mempty
+  let
+    title = (B.stringUtf8 (Pkg.toString pkg))
+  in
+  makeHtml title mempty (makeOgpMetadata title Nothing)
 
 
 
 -- VERSION
 
 
-version :: Pkg.Name -> Pkg.Version -> Maybe Module.Raw -> Snap ()
-version pkg@(Pkg.Name _ prjct) vsn maybeName =
+version :: Pkg.Name -> Pkg.Version -> Maybe Module.Raw -> Maybe Text.Text -> Snap ()
+version pkg@(Pkg.Name _ prjct) vsn maybeName maybeDescription =
   let
     versionString =
       Pkg.versionToString vsn
@@ -58,6 +61,7 @@ version pkg@(Pkg.Name _ prjct) vsn maybeName =
       ++ Text.unpack prjct ++ " " ++ versionString
   in
   makeHtml (B.stringUtf8 title) (makeCanonicalLink pkg maybeName)
+    (makeOgpMetadata (B.stringUtf8 title) maybeDescription)
 
 
 
@@ -106,19 +110,35 @@ renames =
   (,)
 
 
+-- OGP METADATA
+
+makeOgpMetadata :: B.Builder -> Maybe Text.Text -> B.Builder
+makeOgpMetadata title maybeDescription =
+  let
+    description =
+      maybe "" (B.stringUtf8 . Text.unpack . \d ->
+          [r|<meta property="og:description" content="|] <> d <> [r|">|]
+        ) maybeDescription
+  in
+  [r|<meta property="og:type" content="website">
+  <meta property="og:site_name" content="Elm Packages">
+  <meta property="og:title" content="|] <> title <> [r|">
+  <meta property="og:image" content="https://package.elm-lang.org/assets/elm_logo.svg">|]
+    <> description
+
 
 -- SKELETON
 
 
-makeHtml :: B.Builder -> B.Builder -> Snap ()
-makeHtml title canonicalLink =
+makeHtml :: B.Builder -> B.Builder -> B.Builder -> Snap ()
+makeHtml title canonicalLink ogpMetadata =
   writeBuilder $
     [r|<!DOCTYPE HTML>
 <html>
 <head>
   <meta charset="UTF-8">
   <link rel="shortcut icon" size="16x16, 32x32, 48x48, 64x64, 128x128, 256x256" href="/assets/favicon.ico">
-  <title>|] <> title <> [r|</title>|] <> canonicalLink <> [r|
+  <title>|] <> title <> [r|</title>|] <> canonicalLink <> ogpMetadata <> [r|
   <link rel="stylesheet" href="/assets/highlight/styles/default.css?|] <> uniqueToken <> [r|">
   <link rel="stylesheet" href="/assets/style.css?|] <> uniqueToken <> [r|">
   <script src="/assets/highlight/highlight.pack.js?|] <> uniqueToken <> [r|"></script>
