Redis and the Gopher protocol
Redis contains an implementation of the Gopher protocol, as specified in the RFC 1436.
The Gopher protocol was very popular in the late ’90s. It is an alternative to the web, and the implementation both server and client side is so simple that the Redis server has just 100 lines of code in order to implement this support.
What do you do with Gopher nowadays? Well Gopher never really died, and lately there is a movement in order for the Gopher more hierarchical content composed of just plain text documents to be resurrected. Some want a simpler internet, others believe that the mainstream internet became too much controlled, and it’s cool to create an alternative space for people that want a bit of fresh air.
Anyway, for the 10th birthday of the Redis, we gave it the Gopher protocol as a gift.
How it works
The Redis Gopher support uses the inline protocol of Redis, and specifically two kind of inline requests that were anyway illegal: an empty request or any request that starts with “/” (there are no Redis commands starting with such a slash). Normal RESP2/RESP3 requests are completely out of the path of the Gopher protocol implementation and are served as usually as well.
If you open a connection to Redis when Gopher is enabled and send it a string like “/foo”, if there is a key named “/foo” it is served via the Gopher protocol.
In order to create a real Gopher “hole” (the name of a Gopher site in Gopher talking), you likely need a script such as the one in https://github.com/antirez/gopher2redis.
SECURITY WARNING
If you plan to put Redis on the internet in a publicly accessible address to server Gopher pages make sure to set a password to the instance. Once a password is set:
- The Gopher server (when enabled, not by default) will kill serve content via Gopher.
- However other commands cannot be called before the client will authenticate.
So use the requirepass option to protect your instance.
To enable Gopher support use the following configuration line.
gopher-enabled yes
Accessing keys that are not strings or do not exit will generate an error in Gopher protocol format.