metosin.jsonista

https://github.com/metosin/jsonista.git


    git clone 'https://github.com/metosin/jsonista.git'
      

      

(ql:quickload :metosin.jsonista)

★166

jsonista

jsonissa / jsonista / jsoniin, jsonilla / jsonilta / jsonille

Clojure library for fast JSON encoding and decoding.

Explicit configuration
Uses jackson-databind
Mostly written in Java for speed
API docs

Much faster than Cheshire while still having all the necessary features for web development. Designed for use with Muuntaja.

Blogged: * Faster JSON processing with jsonista

Latest version

Requires Java1.8+

Quickstart

(require '[jsonista.core :as j])

(j/write-value-as-string {"hello" 1})
;; => "{\"hello\":1}"

(j/read-value *1)
;; => {"hello" 1}

Examples

Changing how map keys are encoded & decoded:

(defn reverse-string [s] (apply str (reverse s)))

(def mapper
  (j/object-mapper
    {:encode-key-fn (comp reverse-string name)
     :decode-key-fn (comp keyword reverse-string)}))

(-> {:kikka "kukka"}
    (doto prn)
    (j/write-value-as-string mapper)
    (doto prn)
    (j/read-value mapper)
    (prn))
; {:kikka "kukka"}
; "{\"akkik\":\"kukka\"}"
; {:kikka "kukka"}

Reading & writing directly into a file:

(def file (java.io.File. "hello.json"))

(j/write-value file {"hello" "world"})

(slurp file)
;; => "{\"hello\":\"world\"}"

(j/read-value file)
;; => {"hello" "world"}

Adding support for joda-time Classes, used by clj-time.

;; [com.fasterxml.jackson.datatype/jackson-datatype-joda "2.9.5"]
(import '[com.fasterxml.jackson.datatype.joda JodaModule])
(import '[org.joda.time LocalDate])

(def mapper
  (j/object-mapper
    {:modules [(JodaModule.)]}))

(j/write-value-as-string (LocalDate. 0) mapper)
; "\"1970-01-01\""

Performance

All standard encoders and decoders are written in Java
Protocol dispatch with read-value & write-value
Jackson ObjectMapper is used directly
Small functions to support JVM Inlining

See perf-tests for details.

encode

decode

License

Distributed under the Eclipse Public License 2.0.