use messina for logging in production.

README.md

@@ -138,6 +138,10 @@ If `DEBUG` is defined in the environment (even as an empty string),
 then some assets will be always be regenerated on-the-fly, which
 is useful for debugging.
 
+If `DEBUG` is *not* defined then [messina][] will be used for logging
+and you may want to set its `GRAYLOG_*` environment variables
+accordingly.
+
 ## Running Tests
 
 To run the test suite, run `npm test`.
@@ -154,3 +158,4 @@ There's also a manual test suite at http://localhost:3000/manual-test/.
   [permission]: http://blitline.com/docs/s3_permissions
   [Discourse]: http://discourse.org/
   [Webmaker Discourse]: http://discourse.webmaker.org/t/webmaker-screenshots/331
+  [messina]: https://www.npmjs.com/package/messina

app.js

@@ -1,5 +1,6 @@
 var express = require('express');
 var morgan = require('morgan');
+var messina = require('messina');
 var browserify = require('browserify');
 var bodyParser = require('body-parser');
 
@@ -14,15 +15,24 @@ var bundlejs;
 var screenshotConfig = new ScreenshotConfig();
 var redisCache = new RedisCache(process.env.REDIS_URL ||
                                 process.env.REDISTOGO_URL);
+var log = messina('webmaker-screenshot');
 var app = express();
 
+if (!DEBUG) log.catchFatal();
+
 redisCache.client.on('error', function(err) {
   // Hopefully we've just temporarily lost connection to the
   // server.
-  console.log(err);
+  if (DEBUG)
+    console.log(err.message);
+  else
+    log.error(err.message);
 });
 
-if (DEBUG) app.use(morgan('dev'));
+if (DEBUG)
+  app.use(morgan('dev'));
+else
+  app.use(log.middleware());
 
 app.use(bodyParser.json());
 
@@ -69,6 +79,15 @@ app.use(function(req, res, next) {
 
 app.use(express.static(__dirname + '/static'));
 
+app.use(function(err, req, res, next) {
+  if (DEBUG) {
+    console.log(err.stack);
+    return res.type("text/plain").status(500).send(err.stack);
+  } else
+    log.error(err.stack);
+  res.status(500).send("Internal Server Error");
+});
+
 app.listen(PORT, function() {
   console.log('listening on port ' + PORT);
 });

package.json

@@ -4,12 +4,13 @@
   "description": "Take thumbnail screenshots of Webmaker makes.",
   "dependencies": {
     "body-parser": "~1.2.0",
-    "redis": "0.12.1",
-    "underscore": "1.7.0",
     "browserify": "8.1.1",
     "express": "~4.2.0",
+    "messina": "^0.1.2",
+    "morgan": "^1.5.1",
+    "redis": "0.12.1",
     "request": "2.34.0",
-    "morgan": "^1.5.1"
+    "underscore": "1.7.0"
   },
   "devDependencies": {
     "nock": "0.57.0",