Regular expression (regexp) matcher

[vnxme]

Summary

The idea behind regexp matcher is to allow low-level packet matching. It's pretty simple under the hood, but actually very powerful. With this matcher Caddy can multiplex virtually any protocol, if a regular expression syntax is enough to distinguish the desired one from others.

Code examples

Proxy a connection starting with a 0xFFEEDD000000 sequence to another machine

{
  "apps": {
    "layer4": {
      "servers": {
        "example": {
          "listen": ["0.0.0.0:443"],
          "routes": [
            {
              "handle": [
                {
                  "handler": "proxy",
                  "upstreams": [
                    {"dial": ["another.machine.local:456"]}
                  ]
                }
              ],
              "match": [
                {"regexp": {"count": 6, "pattern": "^\\xFF\\xEE\\xDD\\x00\\x00\\x00$"}}
              ]
            },
            {
              "handle": [
                {
                  "handler": "tls"
                },
                {
                  "handler": "proxy",
                  "upstreams": [
                    {"dial": ["localhost:8080"]}
                  ]
                }
              ],
              "match": [
                {"tls": {}}
              ]
            }
          ]
        }
      }
    }
  }
}

[mholt]

This looks great! I'm excited to see how people use it.

[mholt]

LGTM! Anything else before we merge it?

[vnxme]

Rebased onto master and added integration tests. I think, it's ready to be merged now.

[mholt]

Awesome! Thanks!