Support redirects by regular expression in declarative WebRequest API

chrome/common/extensions/api/declarative_web_request.json

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 [
   {
     "namespace": "declarativeWebRequest",
     "documentation_permissions_required": ["declarative", "declarativeWebRequest"],
     "types": [
       {
@@ skipping 48 matching lines @@
         "description": "Declarative event action that redirects a network request to an empty document.",
         "type": "object",
         "properties": {
           "instanceType": {
             "type": "string", "enum": ["declarativeWebRequest.RedirectToEmptyDocument"],
             "nodoc": true
           }
         }
       },
       {
+        "id": "declarativeWebRequest.RedirectByRegEx",
+        "description": "Redirects a request by applying a regular expression on the URL. The regular expressions use the <a href=\"http://code.google.com/p/re2/wiki/Syntax\">RE2 syntax</a>.",
+        "type": "object",
+        "properties": {
+          "instanceType": {
+            "type": "string", "enum": ["declarativeWebRequest.RedirectByRegEx"],
+            "nodoc": true
+          },
+          "from": {
+            "type": "string",
+            "description": "A match pattern that may contain capture groups."
+          },
+          "to": {
+            "type": "string",
+            "description": "Destination pattern."
+          },
+          "perlCaptureGroupStyle": {

[Matt Perry, 2012/05/31 20:22:17]

I don't think we should support this. We should just stick to one capture group
style. Probably RE2, since that is what we're planning on using, and we can get
rid of the conversion step once we switch.

[battre, 2012/05/31 21:30:40]

This will create a certain burden for HTTPS Everywhere who cannot use their
default rules which all contain $ for capture groups (which is the default for
JavaScript RegEx, RE2 is the outlier). If I don't hear anything contrary by
tomorrow, I will remove this feature. I have a slight preference for leaving it
in, though.

[Matt Perry, 2012/05/31 21:38:56]

I see... Maybe we should default to $ syntax, then? Though I presume RE2 syntax
is different in other ways as well, right?

My order of preferences is:
1. Use $ always, with a converter when we switch to RE2.
2. Leave this option (keep patch as-is).

But I don't feel that strongly, so I'll leave it up to you.

[battre, 2012/06/14 12:48:09]

Done. I have followed your preference 1.

I did not move the conversion from $ to \\ syntax in a central place, yet,
because the Downloads API does not use RegEx for substitutions.

+            "type": "boolean",
+            "description": "If set to true, capture groups are referenced in the perl syntax ($1, $2, ...) instead of the RE2 syntax (\\1, \\2, ...). Defaults to false.",
+            "optional": true
+          }
+        }
+      },
+      {
         "id": "declarativeWebRequest.SetRequestHeader",
         "description": "Sets the request header of the specified name to the specified value. If a header with the specified name did not exist before, a new one is created. Header name comparison is always case-insensitive. Each request header name occurs only once in each request.",
         "type": "object",
         "properties": {
           "instanceType": {
             "type": "string", "enum": ["declarativeWebRequest.SetRequestHeader"],
             "nodoc": true
           },
           "name": {
             "type": "string",
@@ skipping 83 matching lines @@
         "options": {
           "supportsListeners": false,
           "supportsRules": true,
           "conditions": ["declarativeWebRequest.RequestMatcher"],
           "actions": [
             "declarativeWebRequest.AddResponseHeader",
             "declarativeWebRequest.CancelRequest",
             "declarativeWebRequest.RedirectRequest",
             "declarativeWebRequest.RedirectToTransparentImage",
             "declarativeWebRequest.RedirectToEmptyDocument",
+            "declarativeWebRequest.RedirectByRegEx",
             "declarativeWebRequest.SetRequestHeader",
             "declarativeWebRequest.RemoveRequestHeader",
             "declarativeWebRequest.RemoveResponseHeader",
             "declarativeWebRequest.IgnoreRules"
           ]
         }
       }
     ]
   }
 ]