marema31/villip repository overview

⁠villip

⁠Simple HTTP proxy that can do :

⁠- string replacement on the content of proxyfied requests/responses

⁠- header set/replacement of proxyfied requests/responses

Villip can be used for containerization of legacy web application that provide absolute path in the page by replacing all the absolute link to the correct one without modifying the application.

The replacement will be also done in Location header if the proxyfied site returns an HTTP 301 or 302 code.

Villip can also be used to replace or set a Header value in the HTTP request/reponse

⁠Usage

Configuration of Villip is done via environments variables or a folder containing YAML files. More than one filter can be described (one by environment variable and the others by configuration files). Each filter must be listening to a different TCP port.

⁠Environment variables

⁠YAML/JSON configuration files

Each YAML/JSON files in the folder pointed by VILLIP_FOLDER environment variable contains the configuration of a filter, the format of these files correspond the same parameter in environment variable formet.

The example below give the overall YAML structure of configuration file when using all attributes.

---
port: 8081
force: true
url: "http://localhost:1234/url1"
dump:
  folder: /var/log/villip/dump
  urls:
    - /books/
    - /movies/
response:         #the http response config part
  replace:
    - from: "book"
      to: "smartphone"
      urls:
        - /youngster/
    - from: "dance"
      to: "chat"
      urls:
        - /youngsters/
        - /geeks/
    - from: "meeting"
      to: "texting"
  header:
    - name: "X-community" # Beware that Vilip will Canonicalize your header name (Mime convention) X-ENV will be converted to X-Env
      value: "In real life"
      force: false  #if force = false the header value is set or replaced only if the header does not exist or if value is empty
      add: false # if true a new header line is added
request:        #the http request config part
  replace:
    - from: "book"
      to: "smartphone"
      urls:
        - /youngster/
    - from: "dance"
      to: "chat"
      urls:
        - /youngsters/
        - /geeks/
  header:
    - name: "X-community"
      value: "In real life"
      force: false
restricted:
  - "192.168.1.0/24"
  - "192.168.8.0/24"
token:
  - header: X-MY-TOKEN
    value: "123"
    action: "accept"
  - header: X-MMYTOKEN
    value: "456"
    action: "accept"
  - header: X-MMYTOKEN
    value: "789"
    action: "reject"
  - header: X-MMYSECONDTOKEN
    value: "ABC"
    action: "accept"
  - header: X-MMYTHIRDTOKEN
    action: "notempty"
content-types:
  - "text/html"
  - "application/json"

⁠Conditionnal proxy

More than one file can refer to the same port, in this case all except one must have at a token or restricted attribute. Villip will proxifies the request to one of the definition that will be fulfilled by the request condition (on header and/or source IP). For token attribute, the condition on same header will be combined by logical OR but condition on different header are combined by logical AND operation.

⁠Disclaimer

I use this application for development environment, security was not a concern for this tool. Do not use it for production environment without being sure of what you are doing

⁠Contribution

I've made this project as a real use case to learn Golang. I've tried to adopt the Go mindset but I'm sure that other gophers could do better.

If this project can be useful for you, feel free to open issues, propose documentation updates or even pull request.

Contributions are of course always welcome!

1. Fork marema31/villip (https://github.com/marema31/villip/fork⁠)
2. Create a feature branch
3. Commit your changes
4. Create a Pull Request

See CONTRIBUTING.md⁠ for details.

⁠License

Copyright (c) 2019-present Marc Carmier⁠

Licensed under BSD-2 Clause License⁠