Clojure base64 encoding

Question

I want something as simple as \"string\" -> base64. With the older base64.encode-str it was easy (and sounded \"more clojure\", but the newer clojure.data.codec.base64

Answer 1

Possible duplicate of Clojure equivalent of python's base64 encode and decode

The Tupelo library has Clojure wrappers around the base Java Base64 and Base64Url functionality. A look at the unit tests show the code in action:

(ns tst.tupelo.base64
  (:require [tupelo.base64 :as b64] ))

code-str    (b64/encode-str  orig)
result      (b64/decode-str  code-str) ]
(is (= orig result))

where the input & output values are plain strings (there is also a variant for byte arrays).

The API docs are here.

Answer 2

Four years later, but I think this is worth mentioning if you're at JDK 1.8 or greater. It just uses java.util.Base64

To Encode String -> Base64:

(:import java.util.Base64)

(defn encode [to-encode]
  (.encode (Base64/getEncoder) (.getBytes to-encode)))

To Encode String -> Base64 (String):

(:import java.util.Base64)

(defn encode [to-encode]
  (.encodeToString (Base64/getEncoder) (.getBytes to-encode)))

To Decode Base64 (byte[] or String) -> String:

(:import java.util.Base64)

(defn decode [to-decode]
  (String. (.decode (Base64/getDecoder) to-decode)))

Answer 3

For those trying (as I was) to turn images into data URIs (for embedding images in HTML):

(defn data-uri
  [imagepath]
  (str
   "data:image/"
   (second
    (re-find #"\.(.*$)" imagepath))
   ";base64,"
   (.encodeToString
    (java.util.Base64/getEncoder)
    (org.apache.commons.io.FileUtils/readFileToByteArray
     (clojure.java.io/file filepath)))))

Answer 4

There's one more step needed for the other answer: converting the byte-array result of encode into a string. Here's what I do:

(:require [clojure.data.codec.base64 :as b64])

(defn string-to-base64-string [original]
  (String. (b64/encode (.getBytes original)) "UTF-8"))

Answer 5

You can use encode function and pass array of bytes:

(encode (.getBytes "Hello world!"))

Answer 6

ztellman/byte-transforms also support base64 encode/decode.

(encode "hello" :base64 {:url-safe? true})