Add a subdir parameter in config

config.json.default

 {
-  "port": "3000"
+  "port": "3000",
+  "subdir": "generateur-slogans/"
 }

srv.js

@@ -107,7 +107,9 @@ app.get('/generate.png', function (req, res) {
 });
 
 app.get('/', function(req, res) {
-  res.render('index', {host: req.headers.host, imageParams: req._parsedUrl.query});
+  res.render('index', {host: req.headers.host,
+		       imageParams: req._parsedUrl.query,
+		       subdir: config.subdir});
 })
 
 app.listen(process.env.PORT || config.port || 80);

views/index.ejs

@@ -6,8 +6,8 @@
     <meta name="twitter:card" content="summary_large_image" />
     <meta property="og:title" content="Soutenez La Quadrature du Net !" />
     <meta property="og:description" content="Soutenez La Quadrature du Net !" />
-    <meta property="og:url" content="http://<%= host %>?<%= imageParams %>" />
-    <meta property="og:image" content="http://<%= host %>/generate.png?<%= imageParams %>" />
+    <meta property="og:url" content="http://<%= host %>/<%= subdir %>?<%= imageParams %>" />
+    <meta property="og:image" content="http://<%= host %>/<%= subdir %>/generate.png?<%= imageParams %>" />
     <meta property="og:image:width" content="600" />
     <meta property="og:image:height" content="413" />
     <meta property="og:type" content="website" />