Added customizable og-metadata to notes

Signed-off-by: Erik Michelson <erik@liltv.de>

lib/models/note.js

@@ -409,9 +409,18 @@ module.exports = function (sequelize, DataTypes) {
       if (meta.GA && (typeof meta.GA === 'string' || typeof meta.GA === 'number')) { _meta.GA = meta.GA }
       if (meta.disqus && (typeof meta.disqus === 'string' || typeof meta.disqus === 'number')) { _meta.disqus = meta.disqus }
       if (meta.slideOptions && (typeof meta.slideOptions === 'object')) { _meta.slideOptions = meta.slideOptions }
+      if (meta.opengraph && (typeof meta.opengraph === 'object')) { _meta.opengraph = meta.opengraph }
     }
     return _meta
   }
+  Note.parseOpengraph = function (meta, title) {
+    var _ogdata = {}
+    if (meta.opengraph) { _ogdata = meta.opengraph }
+    if (!(_ogdata.title && (typeof _ogdata.title === 'string' || typeof _ogdata.title === 'number'))) { _ogdata.title = title }
+    if (!(_ogdata.description && (typeof _ogdata.description === 'string' || typeof _ogdata.description === 'number'))) { _ogdata.description = meta.description || '' }
+    if (!(_ogdata.type && (typeof _ogdata.type === 'string'))) { _ogdata.type = 'website' }
+    return _ogdata
+  }
   Note.updateAuthorshipByOperation = function (operation, userId, authorships) {
     var index = 0
     var timestamp = Date.now()

lib/response.js

@@ -98,12 +98,14 @@ function responseCodiMD (res, note) {
   var meta = models.Note.parseMeta(extracted.meta)
   var title = models.Note.decodeTitle(note.title)
   title = models.Note.generateWebTitle(meta.title || title)
+  var opengraph = models.Note.parseOpengraph(meta, title)
   res.set({
     'Cache-Control': 'private', // only cache by client
     'X-Robots-Tag': 'noindex, nofollow' // prevent crawling
   })
   res.render('codimd.ejs', {
-    title: title
+    title: title,
+    opengraph: opengraph
   })
 }
 
@@ -217,6 +219,7 @@ function showPublishNote (req, res, next) {
       var updatetime = note.lastchangeAt
       var title = models.Note.decodeTitle(note.title)
       title = models.Note.generateWebTitle(meta.title || title)
+      var ogdata = models.Note.parseOpengraph(meta, title)
       var data = {
         title: title,
         description: meta.description || (markdown ? models.Note.generateDescription(markdown) : null),
@@ -232,7 +235,8 @@ function showPublishNote (req, res, next) {
         GA: meta.GA,
         disqus: meta.disqus,
         cspNonce: res.locals.nonce,
-        dnt: req.headers.dnt
+        dnt: req.headers.dnt,
+        opengraph: ogdata
       }
       return renderPublish(data, res)
     }).catch(function (err) {

public/views/codimd/head.ejs

@@ -4,6 +4,10 @@
 <meta name="apple-mobile-web-app-capable" content="yes">
 <meta name="apple-mobile-web-app-status-bar-style" content="black">
 <meta name="mobile-web-app-capable" content="yes">
+<% for (var og in opengraph) { %>
+<% if (opengraph.hasOwnProperty(og) && opengraph[og].trim() !== '') { %>
+<meta property="og:<%= og %>" content="<%= opengraph[og] %>">
+<% }} %>
 <title><%= title %></title>
 <link rel="icon" type="image/png" href="<%- serverURL %>/favicon.png">
 <link rel="apple-touch-icon" href="<%- serverURL %>/apple-touch-icon.png">

public/views/pretty.ejs

@@ -14,6 +14,10 @@
     <% if(typeof description !== 'undefined' && description) { %>
     <meta name="description" content="<%= description %>">
     <% } %>
+    <% for (var og in opengraph) { %>
+    <% if (opengraph.hasOwnProperty(og) && opengraph[og].trim() !== '') { %>
+    <meta property="og:<%= og %>" content="<%= opengraph[og] %>">
+    <% }} %>
     <title><%= title %></title>
     <link rel="icon" type="image/png" href="<%- serverURL %>/favicon.png">
     <link rel="apple-touch-icon" href="<%- serverURL %>/apple-touch-icon.png">