Use dependencies for unpkg URLs in module mode

package.json

@@ -9,6 +9,7 @@
     "test": "node scripts/test.js --env=jsdom"
   },
   "dependencies": {
+    "babel-plugin-unpkg-rewrite": "^2.0.0",
     "cors": "^2.8.1",
     "countries-list": "^1.3.2",
     "csso": "^3.1.1",

server/middleware/packageURL.js

@@ -2,9 +2,9 @@ const validateNPMPackageName = require('validate-npm-package-name')
 const parsePackageURL = require('../utils/parsePackageURL')
 
 const KnownQueryParams = {
-  expand: true,
   main: true,
-  meta: true
+  meta: true,
+  module: true
 }
 
 function isKnownQueryParam(param) {

server/middleware/serveFile.js

@@ -17,9 +17,11 @@ const AutoIndex = !process.env.DISABLE_INDEX
 const MaximumDepth = 128
 
 const FileTransforms = {
-  expand: function (file, callback) {
+  expand: function (file, dependencies, callback) {
     const options = {
-      plugins: [ unpkgRewrite ]
+      plugins: [
+        unpkgRewrite(dependencies)
+      ]
     }
 
     babel.transformFile(file, options, function (error, result) {
@@ -60,8 +62,13 @@ function serveFile(req, res, next) {
       'Cache-Tag': 'file'
     })
 
-    if (contentType === 'application/javascript' && req.query.expand != null) {
-      FileTransforms.expand(file, function (error, code) {
+    if (contentType === 'application/javascript' && req.query.module != null) {
+      const dependencies = Object.assign({},
+        req.packageConfig.peerDependencies,
+        req.packageConfig.dependencies
+      )
+
+      FileTransforms.expand(file, dependencies, function (error, code) {
         if (error) {
           console.error(error)
           res.status(500).type('text').send(`Cannot generate index page for ${req.packageSpec}${req.filename}`)