Rename "roles" to "units". Put units in their own folders.

lib/units/storage/plugins/image/index.js

@@ -0,0 +1,52 @@
+var http = require('http')
+
+var express = require('express')
+
+var logger = require('../../../../util/logger')
+var requtil = require('../../../../util/requtil')
+
+var parseCrop = require('./param/crop')
+var parseGravity = require('./param/gravity')
+var get = require('./task/get')
+var transform = require('./task/transform')
+
+module.exports = function(options) {
+  var log = logger.createLogger('storage:plugins:image')
+    , app = express()
+    , server = http.createServer(app)
+
+  app.set('strict routing', true)
+  app.set('case sensitive routing', true)
+  app.set('trust proxy', true)
+
+  app.get(
+    '/api/v1/s/image/:id/*'
+  , requtil.limit(options.concurrency, function(req, res) {
+      return get(req.url, options)
+        .then(function(stream) {
+          return transform(stream, {
+            crop: parseCrop(req.query.crop)
+          , gravity: parseGravity(req.query.gravity)
+          })
+        })
+        .then(function(out) {
+          res.status(200)
+          out.pipe(res)
+        })
+        .catch(function(err) {
+          log.error(
+            'Unable to transform resource "%s"'
+          , req.params.id
+          , err.stack
+          )
+          res.status(500)
+            .json({
+              success: false
+            })
+        })
+    })
+  )
+
+  server.listen(options.port)
+  log.info('Listening on port %d', options.port)
+}