From aa2538fb50b8986b7cd9785b9d2769da9b2fef7d Mon Sep 17 00:00:00 2001
From: Lars Trieloff <trieloff@adobe.com>
Date: Wed, 24 Apr 2019 12:10:56 +0000
Subject: [PATCH] feat(html): rewrite static asset references to ESI includes
 that provide stable URLs

When run in production, all `<script src>` and `<link href>` references pointing to external assets will be rewritten to become ESI includes of the same URL, with an added extension that can be resolved into a stable URL

Fixes #224
---
 src/defaults/html.pipe.js |  2 ++
 test/testRewriteStatic.js | 71 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 73 insertions(+)
diff --git a/src/defaults/html.pipe.js b/src/defaults/html.pipe.js
index 3283533f0..edcbf26c0 100644
--- a/src/defaults/html.pipe.js
+++ b/src/defaults/html.pipe.js
@@ -31,6 +31,7 @@ const validate = require('../utils/validate');
 const { cache, uncached } = require('../html/shared-cache');
 const embeds = require('../html/find-embeds');
 const parseFrontmatter = require('../html/parse-frontmatter');
+const rewriteLinks = require('../html/static-asset-links');
 
 /* eslint no-param-reassign: off */
 /* eslint newline-per-chained-call: off */
@@ -62,6 +63,7 @@ const htmlpipe = (cont, payload, action) => {
     .after(cache).when(uncached)
     .after(key)
     .after(debug)
+    .after(rewriteLinks).when(production)
     .after(flag).expose('esi').when(esi) // flag ESI when there is ESI in the response
     .error(selectStatus(production()));
 
diff --git a/test/testRewriteStatic.js b/test/testRewriteStatic.js
index 974821281..26fbf98ad 100644
--- a/test/testRewriteStatic.js
+++ b/test/testRewriteStatic.js
@@ -11,7 +11,15 @@
  */
 /* eslint-env mocha */
 const assert = require('assert');
+const { Logger } = require('@adobe/helix-shared');
 const rewrite = require('../src/html/static-asset-links');
+const { pipe } = require('../src/defaults/html.pipe.js');
+
+
+const logger = Logger.getTestLogger({
+  // tune this for debugging
+  level: 'info',
+});
 
 function rw(content) {
   return rewrite({
@@ -24,6 +32,69 @@ function rw(content) {
   }).response.body;
 }
 
+describe('Integration Test Static Asset Rewriting', () => {
+  let production;
+
+  before('Fake Production Mode', () => {
+    // eslint-disable-next-line no-underscore-dangle
+    production = process.env.__OW_ACTIVATION_ID;
+    // eslint-disable-next-line no-underscore-dangle
+    process.env.__OW_ACTIVATION_ID = 'fake';
+  });
+
+  it('Test static asset rewriting in full pipeline', async () => {
+    const context = {
+      content: {
+        body: 'Hello World',
+      },
+    };
+    const action = {
+      request: {
+        params: {},
+      },
+      logger,
+    };
+    const once = ({ content }) => ({
+      response: {
+        status: 200,
+        body: `<html>
+  <head>
+    <title>${content.document.body.textContent}</title>
+    <script src="index.js"></script>
+    <link rel="stylesheet" href="style.css" />
+  </head>
+  <body>
+    ${content.document.body.innerHTML}
+    <script>
+      alert('ok');
+    </script>
+  </body>
+</html>`,
+      },
+    });
+
+    const res = await pipe(once, context, action);
+
+    assert.equal(res.response.body, `<html><head>
+    <title>Hello World</title>
+    <script src='<!-- bad ESI request: bad ESI request -->'></script>
+    <link rel="stylesheet" href='<!-- bad ESI request: bad ESI request -->'>
+  </head>
+  <body>
+    <p>Hello World</p>
+    <script>
+      alert('ok');
+    </script>
+  
+</body></html>`);
+  });
+
+  after('Reset Production Mode', () => {
+    // eslint-disable-next-line no-underscore-dangle
+    process.env.__OW_ACTIVATION_ID = production;
+  });
+});
+
 describe('Test Static Asset Rewriting', () => {
   it('Ignores non-HTML', () => {
     assert.deepEqual(rewrite({
