Allow {png,gif,jpg,pdf} output.

package.json

@@ -9,9 +9,10 @@
   },
   "license": "CC0",
   "dependencies": {
-    "dot": ">=1.0.2",
+    "dot": "~1.0.2",
     "svgo": "~0.4.2",
     "canvas": "~1.1.2",
+    "phantomjs": "~1.9.2-6",
     "es6-promise": "~0.1.1",
     "camp": "~13.11.9"
   },

phantomjs-svg2png.js

@@ -0,0 +1,27 @@
+var page = require('webpage').create();
+var system = require('system');
+var svg = system.args[1];
+var svgUrl = 'data:image/svg+xml,' + window.encodeURI(svg);
+var tmpFile = system.args[2];
+
+page.viewportSize = getSvgDimensions(svg);
+page.open(svgUrl, function(status) {
+  if (status !== 'success') {
+    console.error('Failed to load the following SVG data:');
+    console.error(svgUrl);
+    phantom.exit(1);
+  } else {
+    page.render(tmpFile);
+    phantom.exit();
+  }
+});
+
+function getSvgDimensions(svg) {
+  var frag = window.document.createElement('div');
+  frag.innerHTML = svg;
+  var svgRoot = frag.querySelector('svg');
+  return {
+    width: parseFloat(svgRoot.getAttribute('width') || 80),
+    height: parseFloat(svgRoot.getAttribute('height') || 19)
+  };
+}

server.js

@@ -2,6 +2,7 @@ var camp = require('camp').start({
   port: process.env.PORT||+process.argv[2]||80
 });
 var badge = require('./badge.js');
+var svg2img = require('./svg-to-img.js');
 var serverStartTime = new Date((new Date()).toGMTString());
 
 // Escapes `t` using the format specified in
@@ -18,12 +19,14 @@ function escapeFormat(t) {
 
 function sixHex(s) { return /^[0-9a-fA-F]{6}$/.test(s); }
 
-camp.route(/^\/(([^-]|--)+)-(([^-]|--)+)-(([^-]|--)+).svg$/,
+camp.route(/^\/(([^-]|--)+)-(([^-]|--)+)-(([^-]|--)+).(svg|png|gif|jpg|pdf)$/,
   function(data, match, end, ask) {
     var subject = escapeFormat(match[1]);
     var status = escapeFormat(match[3]);
     var color = escapeFormat(match[5]);
-    ask.res.setHeader('Content-Type', 'image/svg+xml');
+    var format = match[7];
+
+    // Cache management.
     var cacheDuration = (3600*24*1)|0;  // 1 day.
     ask.res.setHeader('Cache-Control', 'public, max-age=' + cacheDuration);
     if (+(new Date(ask.req.headers['if-modified-since'])) >= +serverStartTime) {
@@ -32,6 +35,8 @@ camp.route(/^\/(([^-]|--)+)-(([^-]|--)+)-(([^-]|--)+).svg$/,
       return;
     }
     ask.res.setHeader('Last-Modified', serverStartTime.toGMTString());
+
+    // Badge creation.
     try {
       var badgeData = {text: [subject, status]};
       if (sixHex(color)) {
@@ -39,16 +44,31 @@ camp.route(/^\/(([^-]|--)+)-(([^-]|--)+)-(([^-]|--)+).svg$/,
       } else {
         badgeData.colorscheme = color;
       }
-      badge(badgeData, function(res) {
-        end(null, {template: streamFromString(res)});
-      });
+      badge(badgeData, makeSend(format, ask.res, end));
     } catch(e) {
-      badge({text: ["error", "bad badge"], colorscheme: "red"}, function(res) {
-        end(null, {template: streamFromString(res)});
-      });
+      badge({text: ["error", "bad badge"], colorscheme: "red"},
+        makeSend(format, ask.res, end));
     }
 });
 
+function makeSend(format, askres, end) {
+  if (format === 'svg') {
+    return function(res) { sendSVG(res, askres, end); };
+  } else {
+    return function(res) { sendOther(format, res, askres, end); };
+  }
+}
+
+function sendSVG(res, askres, end) {
+  askres.setHeader('Content-Type', 'image/svg+xml');
+  end(null, {template: streamFromString(res)});
+}
+
+function sendOther(format, res, askres, end) {
+  askres.setHeader('Content-Type', 'image/' + format);
+  svg2img(res, format, askres);
+}
+
 var stream = require('stream');
 function streamFromString(str) {
   var newStream = new stream.Readable();

svg-to-img.js

@@ -0,0 +1,22 @@
+var fs = require('fs');
+var os = require('os');
+var path = require('path');
+var phantom = require('phantomjs');
+var childProcess = require('child_process');
+var phantomScript = path.join(__dirname, 'phantomjs-svg2png.js');
+
+module.exports = function (svg, format, out, cb) {
+  var tmpFile = path.join(os.tmpdir(),
+      "svg2img-" + (Math.random()*2147483648|0) + "." + format);
+  // Conversion to PNG happens in the phantom script.
+  childProcess.execFile(phantom.path, [phantomScript, svg, tmpFile],
+  function(err, stdout, stderr) {
+    if (stdout) { console.log(stdout); }
+    if (stderr) { console.log(stderr); }
+    if (err != null) { console.error(err.stack); if (cb) { cb(err); } return; }
+    var inStream = fs.createReadStream(tmpFile);
+    inStream.pipe(out);
+    // Remove the temporary file after use.
+    inStream.on('end', function() { fs.unlink(tmpFile, cb); });
+  });
+};