feat(chromium): add --chromium-clear-storage to clear local storage between conversions (#919)

test/integration/features/chromium_convert_url.feature

@@ -22,6 +22,41 @@ Feature: /forms/chromium/convert/url
       Page 1
       """
 
+  # localStorage is per-origin and shared by the long-lived browser, so without
+  # clearing it accumulates across same-origin conversions.
+  # See https://github.com/gotenberg/gotenberg/issues/919.
+  Scenario: POST /forms/chromium/convert/url (localStorage leaks without clearing)
+    Given I have a default Gotenberg container
+    Given I have a static server
+    When I make a "POST" request to Gotenberg at the "/forms/chromium/convert/url" endpoint with the following form data and header(s):
+      | url                       | http://host.docker.internal:%d/html/testdata/local-storage-html/index.html | field  |
+      | Gotenberg-Output-Filename | foo                                                                        | header |
+    Then the response status code should be 200
+    Then the "foo.pdf" PDF should have content matching "localStorageCount=1" at page 1
+    When I make a "POST" request to Gotenberg at the "/forms/chromium/convert/url" endpoint with the following form data and header(s):
+      | url                       | http://host.docker.internal:%d/html/testdata/local-storage-html/index.html | field  |
+      | Gotenberg-Output-Filename | foo                                                                        | header |
+    Then the response status code should be 200
+    Then the "foo.pdf" PDF should have content matching "localStorageCount=2" at page 1
+
+  # With --chromium-clear-storage every conversion clears the origin's
+  # localStorage first, so the counter never carries over.
+  # See https://github.com/gotenberg/gotenberg/issues/919.
+  Scenario: POST /forms/chromium/convert/url (Clear Storage)
+    Given I have a Gotenberg container with the following environment variable(s):
+      | CHROMIUM_CLEAR_STORAGE | true |
+    Given I have a static server
+    When I make a "POST" request to Gotenberg at the "/forms/chromium/convert/url" endpoint with the following form data and header(s):
+      | url                       | http://host.docker.internal:%d/html/testdata/local-storage-html/index.html | field  |
+      | Gotenberg-Output-Filename | foo                                                                        | header |
+    Then the response status code should be 200
+    Then the "foo.pdf" PDF should have content matching "localStorageCount=1" at page 1
+    When I make a "POST" request to Gotenberg at the "/forms/chromium/convert/url" endpoint with the following form data and header(s):
+      | url                       | http://host.docker.internal:%d/html/testdata/local-storage-html/index.html | field  |
+      | Gotenberg-Output-Filename | foo                                                                        | header |
+    Then the response status code should be 200
+    Then the "foo.pdf" PDF should have content matching "localStorageCount=1" at page 1
+
   Scenario: POST /forms/chromium/convert/url (Single Page)
     Given I have a default Gotenberg container
     Given I have a static server

test/integration/features/debug.feature

@@ -83,6 +83,7 @@ Feature: /debug
           "chromium-auto-start": "false",
           "chromium-clear-cache": "false",
           "chromium-clear-cookies": "false",
+          "chromium-clear-storage": "false",
           "chromium-deny-list": "[^file:(?!//\\/tmp/).*]",
           "chromium-deny-private-ips": "false",
           "chromium-deny-public-ips": "false",
@@ -221,6 +222,7 @@ Feature: /debug
           "chromium-auto-start": "false",
           "chromium-clear-cache": "false",
           "chromium-clear-cookies": "false",
+          "chromium-clear-storage": "false",
           "chromium-deny-list": "[^file:(?!//\\/tmp/).*]",
           "chromium-deny-private-ips": "false",
           "chromium-deny-public-ips": "false",

test/integration/testdata/local-storage-html/index.html

@@ -0,0 +1,18 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <title>Local storage counter</title>
+  </head>
+  <body>
+    <!-- Increments a per-origin localStorage counter and renders it, so a value
+         above 1 means a previous conversion of the same origin leaked into this
+         one. See https://github.com/gotenberg/gotenberg/issues/919. -->
+    <pre id="out"></pre>
+    <script>
+      var n = (parseInt(localStorage.getItem("n"), 10) || 0) + 1;
+      localStorage.setItem("n", n);
+      document.getElementById("out").textContent = "localStorageCount=" + n;
+    </script>
+  </body>
+</html>