Open Source Ecosystems

gooreplacer

A browser extension to modify HTTP requests :-)

At first, Gooreplacer is created for redirecting Google Ajaxs/APIs/Fonts to other CDN to bypass Great Firewall, since pages referring those are slow as molasses.

Nowadays, more features have been added to gooreplacer, mainly:

Block request
Modify headers
Export/Import rules, sync between Firefox/Chrome/Edge...
Live Test
i18n

Most users prefer gooreplacer than other similar extensions, HTTPS Everywhere/Redirector, for ease-of-use. Why not give it a try?

Install

Browser	Rate	User

Guides

Currently gooreplacer support 4 functions. Take one exported rules as example:

{
  "createBy": "https://github.com/jiacai2050/gooreplacer",
  "version": "2.0",
  "createAt": "Sun Oct 29 2017 19:55:32 GMT+0800 (CST)",
  "redirect-rules": [
    {
      "src": "ajax.googleapis.com",
      "dst": "ajax.proxy.ustclug.org",
      "kind": "wildcard",
      "enable": true
    }
  ],
  "cancel-rules": [
    {
      "src": "facebook.com",
      "kind": "wildcard",
      "enable": true
    }
  ],
  "request-headers": [
    {
      "src": "google.com",
      "kind": "wildcard",
      "name": "user-agent",
      "value": "gooreplacer",
      "op": "modify",
      "enable": true
    }
  ],
  "response-headers": [
    {
      "src": "google.com",
      "kind": "wildcard",
      "name": "Cookie",
      "op": "cancel",
      "enable": true
    }
  ]
}

redirect-rules used for redirects
cancel-rules used for blocks
request-headers used for modify/cancel http request headers
response-headers used for modify/cancel http response headers

In each rule,

src limit which request it will work on, and it has two types: wildcard and regexp, which is defined in kind key.
dst only required in redirects, means destination
enable turn on/off
op required in request-headers response-headers, has two enum value: cancel or modify
name, value required in request-headers response-headers, means header name(case-insensitive), header value

In redirects, you can use $1 $2 ... to backreference captured groups in case of regexp kind. For example:

{
  "src": "https://search.yahoo.com/search\?p=([a-z]+)",
  "dst": "https://www.google.com/search?q=$1",
  "kind": "regexp",
  "enable": true
}

Then https://search.yahoo.com/search?p=gooreplacer will redirect to https://www.google.com/search?q=gooreplacer

If your rules don't work as expected, use sandbox to test, it can tell what's missing.

NOTE

In order to be compatiable with old versions, redirect-rules key in JSON-rules file can be just rules and have following format:

"rules": {
  "ajax.googleapis.com": {
    "dstURL": "ajax.proxy.ustclug.org",
    "enable": true,
    "kind": "wildcard"
  }
}

According to Google Extension document，headers below can't be modified:
- Authorization
- Cache-Control
- Connection
- Content-Length
- Host
- If-Modified-Since
- If-None-Match
- If-Range
- Partial-Data
- Pragma
- Proxy-Authorization
- Proxy-Connection
- Transfer-Encoding

Development

Gooreplacer is written in pure JavaScript before v1.0, you can check this version at legacy-js-src. After v2.0, gooreplacer get a big rewrite in ClojureScript + Reagent + Antd + React-Bootstrap，which is resident in cljs-src。