Eric Avdey eiri

`jo` and `jg` comparison and cheatsheet

What is it?

Both command line utilities allow to JSON output from a shell.

Links

Formats of syslog

rfc 5424

<PRI>VER TIMESTAMP HOSTNAME APP-NAME PROCID MSGID [SOURCETYPE@NM_IANA key1="val1" key2="val2" etc.]

example: <34>1 2003-10-11T22:14:15.003Z mymachine.example.com su ID47 d25c5bf1 - BOM'su root' failed for lonvick on /dev/pts/8

rfc 3164

TIMESTAMP HOSTNAME APP-NAME[PROCID]: sourcetype="SOURCETYPE" key1="val1" key2="val2" etc.

Error: The operation couldn’t be completed. (com.apple.commerce.client error 500.)

Fix: defaults write com.apple.appstore.commerce Storefront -string "$(defaults read com.apple.appstore.commerce Storefront | sed s/,8/,13/)"

Ref: https://discussions.apple.com/thread/250154403?answerId=250306539022#250306539022

Bash string manipulation cheatsheet

Assignment
Assign `value` to `variable` if `variable` is not already set. Value will be returned. Couple with `:` no-op if return value is to be discarded.	`${variable="value"}` `: ${variable="value"}`

Cheat

Command line utility cheat https://github.com/cheat/cheat is kind of a man alternative.

Installation & configuration

brew install cheat mkdir -p ~/.config/cheat && cheat --init > ~/.config/cheat/conf.yml

edit to following (a list of avail styles at https://github.com/alecthomas/chroma/tree/master/styles)

Grab a data file. "American movies scraped from Wikipedia" is a nice condence set at size 3.4M wget https://raw.githubusercontent.com/prust/wikipedia-movie-data/master/movies.json -O movies.json

Slice movies made from 1920 till 1930 and output them line by line

jq -cr '.[] | select(.year >= 1920 and .year <= 1930)' movies.json

Pass the output to reducer to group by year, calculate total movies per year and accumulate movies into "movies" array in each block

	#!/bin/bash

	# prereq `brew install coreutils jo`

	defcount=1

	display_usage() {
	echo -e "Generate NUMBER of random json objects."
	printf " Usage: %s [NUMBER] (DEFAULT: %s)\n\n" $(basename "$0") $defcount
	}

	FROM node:8.11-alpine

	RUN npm install --global gitbook-cli && \
	gitbook fetch 3.2.2 && \
	gitbook install && \
	npm cache clear --force && \
	rm -rf /tmp/*

	# Fixes https://github.com/GitbookIO/gitbook/issues/1309
	RUN sed -i.bak 's/confirm: true/confirm: false/g' \

	sub.DEFAULT_GOAL := check
	.EXPORT_ALL_VARIABLES:

	CURL_HOME = $(CURDIR)
	JAR = $(CURDIR)/jar

	DB = http://localhost:15984
	ADM_CRD = '{"username":"admin", "password": "admin"}'
	USR_CRD = '{"name":"eiri", "password": "eiri"}'

	KERL_DEFAULT_INSTALL_DIR=/opt/erlang
	KERL_CONFIGURE_OPTIONS="--enable-debug --without-javac --enable-shared-zlib --enable-dynamic-ssl-lib --disable-hipe --enable-smp-support --enable-threads --enable-kernel-poll --with-wx --with-ssl=/usr/local/opt/openssl"