gemini.core

A Clojure library to make Gemini requests that exposes some low-level API to handle network requests.

Usage

Import the library for e.g. with:

user=> (require '[gemini.core :as gemini])

Documentation

fetch makes a Gemini request and returns a map with :request, :meta, :code and :body as keys, or :error if an error occur.

The request needs to be closed afterwards using close.

user=> (gemini/fetch "gemini://gemini.circumlunar.space/")
{:request
 #object[com.omarpolo.gemini.Request 0x3b270767 "com.omarpolo.gemini.Request@3b270767"],
 :meta "gemini://gemini.circumlunar.space/",
 :code 31,
 :body
 #object[java.io.BufferedReader 0x49358b66 "java.io.BufferedReader@49358b66"]}

body-as-string! reads all the response into a string and returns it. It also closes the request automatically.

user=> (-> (gemini/fetch "gemini://gemini.circumlunar.space/")
           gemini/body-as-string!)
"# Project Gemini\n\n## Overview\n\nGemini is a new internet protocol which..."

close closes a request. It needs to be called after every (successful) request.

user=> (let [req (gemini/fetch "...")]
         (when-not (:error req)
           ;; do something with req
           ,,,
           (gemini/close req)))

with-request is a macro like with-open to making connection easily. It automatically closes the request and evaluates the body only when the request is successful, otherwise throws an exception.

user=> (with-request [req (gemini/fetch "gemini://gemini.circumlunar.space/")]
         ,,,)

Streaming content

The :body keyword in the returned map is an instance of a Java BufferedReader, so streaming content is easy.

However, body-as-string! needs to materialise the full reply, so in case of a streaming request it will never return!

text/gemini

This library only implements the network part of Gemini, it doesn't try to handle any kind of content. To handle text/gemini you can use e.g. the gemtext library:

user=> (require '[gemtext.core :as gemtext])
nil
user=> (gemini/with-request [req (gemini/fetch "gemini://gemini.circumlunar.space/")]
         (gemtext/parse (:body req)))
[[:header-1 "Project Gemini"]
 [:text ""]
 [:header-2 "Overview"]
 [:text ""]
 [:text "Gemini is a new internet protocol which:"]
 ,,,]

The gemtext library supports streaming via the gemtext.core/parse transducer:

user=> (gemini/with-request [req (gemini/fetch "gemini://gemini.circumlunar.space/")]
         (transduce gemtext/parser conj [] (line-seq (:body req))))
,,,