jarppe’s gists

jarppe / proxy_byte_channels_example.clj

Created June 16, 2024 12:17

Converting Channel to Java InputStream and OutputStream using proxies

	(ns proxy-byte-channels-example
	(:import (java.io InputStream
	OutputStream)
	(java.nio ByteBuffer)
	(java.net UnixDomainSocketAddress
	StandardProtocolFamily)
	(java.nio.channels ByteChannel
	SocketChannel)
	(java.nio.charset StandardCharsets)))

jarppe / byte_channels_example.clj

Created June 16, 2024 11:58

Simple example for obtaining a ByterChannel to Unix domain socket and converting i/o to java Input and Output streams

	(ns byte-channels-example
	(:import (java.io InputStream
	OutputStream)
	(java.net UnixDomainSocketAddress
	StandardProtocolFamily)
	(java.nio.channels ByteChannel
	SocketChannel
	Channels)
	(java.nio.charset StandardCharsets)))

jarppe / deps.edn

Last active May 22, 2024 12:04

Streaming json

	{:paths ["src/main"]
	:deps {org.clojure/clojure {:mvn/version "1.12.0-alpha11"}
	ring/ring-core {:mvn/version "1.12.1"}
	info.sunng/ring-jetty9-adapter {:mvn/version "0.33.1"}
	metosin/jsonista {:mvn/version "0.3.8"}}}

jarppe / idle-guard.clj

Created October 18, 2021 08:03

Babashka script to shutdown idle host

	#!/usr/local/bin/bb


	(require '[clojure.java.shell :as sh]
	'[clojure.string :as str])
	(import '(java.util.concurrent TimeUnit)
	'(java.time ZoneId ZonedDateTime)
	'(java.time.format DateTimeFormatter))

jarppe / jsonb_diff.sql

Created April 6, 2021 11:18

PostgreSQL function to produce diff of two jsonb objects. Does not support arrays.

	--
	-- Helper function to produce a diff of two jsonb values.
	--
	-- Accepts:
	-- val1: original jsonb value
	-- val2: updated jsonb value
	--
	-- Returns:
	-- jsonb of changed values
	--

jarppe / audit_trail.clj

Last active November 17, 2016 18:24

Return all transactions and all their datoms that have contributed to given entity

	(ns datomic-spike.audit-trail
	(:require [datomic.api :as d]))

	(defn entity-txs
	"Accepts an entity, returns all transactions (as entities) that
	have altered the given entity, sorted by transaction t"
	[e]
	(let [id (:db/id e)
	db (d/entity-db e)
	history (d/history db)]

jarppe / gist:257ac92ce789ca7b9528

Created May 17, 2015 11:08

Map, filter, reduce example, ClojureBridge Helsinki

	(def authors [{:first "Margaret" :last "Atwood" :books 15}
	{:first "Doris" :last "Lessing" :books 67}
	{:first "Ursula" :last "Le Guin" :books 23}
	{:first "Alice" :last "Munro" :books 21}])

	(defn get-name [author]
	(get author :first))

	(defn first-name-short? [author]
	(let [first-name (get-name author)

jarppe / lazy-seq-of-users.clj

Last active August 29, 2015 14:02

lazy-seq of random users from randomuser.me

	; start with: lein try clj-http

	(require '[clj-http.client :as http])

	(defn fetch-random-users [n]
	(->> (http/get "http://api.randomuser.me/" {:query-params {:results n} :as :json})
	:body
	:results
	(map :user)))

jarppe / cout.clj

Last active August 29, 2015 13:56

...because C++ had that one good thing

	(defmacro << [& body]
	(let [[fmt args] (loop [fmt ""
	args []
	[p & more] body]
	(if p
	(cond
	(and (symbol? p) (starts-with (name p) "%")) (recur (str fmt (name p)) (conj args (first more)) (rest more))
	(symbol? p) (recur (str fmt "%s") (conj args p) more)
	(string? p) (recur (str fmt (str p)) args more)
	:else (recur (str fmt "%s") (conj args p) more))

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