Hacker Public Radio Hacker Public Radio

Overview
In the last
episode we looked at how JSON data is structured and saw how
jq could be used to format and print this type of data.
In this episode we'll visit a few of the options to the
jq command and then start on the filters written in the
jq language.
Options used by jq
In general the jq command is invoked thus:
jq [options...] filter [files...]
It can be given data in files or sent to it via the STDIN (standard
in) channel. We saw data being sent this way in the last episode, having
been downloaded by curl.
There are many options to the command, and these are listed in the
manual page and in the online manual. We will
look at a few of them here:

--help or -h

Output the jq help and exit with zero.

-f filename or
--from-file filename

Read filter from the file rather than from a command line, like awk´s
-f option. You can also use ´#´ to make comments in the file.

--compact-output or -c

By default, jq pretty-prints JSON output. Using this
option will result in more compact output by instead putting each JSON
object on a single line.

--color-output or -C and
--monochrome-output or -M

By default, jq outputs colored JSON if writing to a
terminal. You can force it to produce color even if writing to a pipe or
a file using -C, and disable color with
-M.

--tab

Use a tab for each indentation level instead of two spaces.

--indent n

Use the given number of spaces (no more than 7) for indentation.


Notes

The -C option is useful when printing output to the
less command with the colours that jq normally
generates. Use this:
jq -C '.' file.json | less -R
The -R option to less allows colour escape sequences to
pass through.
Do not do what I did recently. Accidentally leaving the
-C option on the command caused formatted.json
to contain all the escape codes used to colour the output:
$ jq -C '.' file.json > formatted.json
This is why jq normally only generates coloured output
when writing to the terminal.

Filters in jq
As we saw in the last episode JSON can contain arrays and objects.
Arrays are enclosed in square brackets and their elements can be any of
the data types we saw last time. So, arrays of arrays, arrays of
objects, and arrays of both of these are all possible.
Objects contain collections of keyed items where the keys are strings
of various types and the values they are associated with can be any of
the data types.
JSON Examples
Simple arrays:
[1,2,3]
[1,2,3,[4,5,6]]
["Hacker","Public","Radio"]
["Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"]
Simple object:
{ "name": "Hacker Public Radio", "type": "podcast"}
This more complex object was generated by the Random User Generator
API.

Today I Learnt, sed
hold/pattern space use.
Sgoti talks
about using sed hold/pattern spaces.

Tags: TIL, sed

I
fixed the ${ls} /usr/bin to ${ls} ${bindir}
issue mentioned in the show.
#!/bin/bash
# License: GPL v3
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see .

#Name: grab-bin.sh
#Purpose: Link your binaries.
#Version: beta 0.07
#Author: SGOTI (Some Guy On The Internet)
#Date: 2023-12-17

#variables:

bindir=/usr/bin/

awk=${bindir}awk
cat=${bindir}cat
chmod=${bindir}chmod
date=${bindir}date
echo=${bindir}echo
find=${bindir}find
ls=${bindir}ls
mktemp=${bindir}mktemp
sed=${bindir}sed
uniq=${bindir}uniq

#start:

${echo} -e "nStep 0: $(${date} +%F), $(${date} +%T)";

# Create the /tmp/ directory to place the files.
function mkt (){
if [ -d /tmp/$(${date} +%F).* ]; then
tmpdir1=$(ls -d /tmp/$(${date} +%F).*)
${echo} -e "The directory already exists.n${tmpdir1}"
else
tmpdir0=$(${mktemp} -d /tmp/$(${date} +%F).XXXXXXXX)
tmpdir1=${tmpdir0}
${find} "${tmpdir1}" -type d -exec ${chmod} -R =700 {} +;
${echo} "Had to create ${tmpdir1}"
fi
}

mkt
${echo} -e "nStep 1: $(${date} +%F), $(${date} +%T)";

# Files created by this script.
tmpdoc0=${tmpdir1}/$(${date} +%Y%m%d)variables.txt
tmpdoc1=${tmpdir1}/$(${date} +%Y%m%d)bash.vim
tmpdoc2=${tmpdir1}/$(${date} +%Y%m%d)sed-script.sed

# Here-document to build the first document (variables.txt).
${cat} > ${tmpdoc0} > ${tmpdoc0}
${sed} -i '/[/d' ${tmpdoc0}

${echo} -e "nStep 2: $(${date} +%F), $(${date} +%T)";

# Bash.vim here-document.
${cat} > ${tmpdoc1} [yY])
${echo} 'User said, "Yes"';
;;

[nN])
${echo} 'User said, "No"';
;;

[qQ])
${echo} "Let's get outta here.";
exit
;;

*)
${echo} "Good Heavens! Someone broke the script I'm writing.";
exit
;;
esac

iabbr here; ${cat} _EOD_2k0

iabbr func function NAME () {}
iabbr if; if []; thenIelse${echo} "Good Heavens!"Ifi4k0A
iabbr ali; alias NAME=''B

iabbr ; ()

EOL1

# bash.vim body.
${ls} -1 ${bindir}
| ${sed} -n ' {
h
s/[^0-9a-zA-Z]//g
G
s/n/ /
s/(.*) (.*)/iabbr 1 ${2}/p
}
' >> ${tmpdoc1}

# Bash.vim here-document second pass.
${cat} >> ${tmpdoc1}
EOL1-5

# bash.vim body second pass.
${ls} -1 ${bindir}
| ${sed} -n ' {
h
s/[^0-9a-zA-Z]//g
G
s/n/ /
s/(.*) (.*)/1=${bindir}2/p
}
' >> ${

Some stuff I use to help make APIs
https://github.com/freeload101/Python/blob/master/Python_Includes_RMcCurdy.py
JAMBOREE.rmccurdy.com for burp suite. Have I done a podcast on
JAMBOREE? I must have... If not I will

table td.shrink {
white-space:nowrap
}
hr.thin {
border: 0;
height: 0;
border-top: 1px solid rgba(0, 0, 0, 0.1);
border-bottom: 1px solid rgba(255, 255, 255, 0.3);
}


New hosts

Welcome to our new host:

Dave Hingley.


Last Month's Shows


Id
Day
Date
Title
Host


4086
Mon
2024-04-01
HPR Community News for March 2024
HPR Volunteers


4087
Tue
2024-04-02
Getting started with the digiKam photo management software
Henrik Hemrin


4088
Wed
2024-04-03
Today I Learnt more Bash tips
Some Guy On The Internet


4089
Thu
2024-04-04
Modifying a Python script with some help from ChatGPT
MrX


4090
Fri
2024-04-05
Playing Civilization III, Part 1
Ahuka


4091
Mon
2024-04-08
Test Driven Development Demo
norrist


4092
Tue
2024-04-09
More man-talk.
Some Guy On The Internet


4093
Wed
2024-04-10
Installing postmarketOS on a PINE64 PinePhone
Claudio Miranda


4094
Thu
2024-04-11

This starts our look at the details of playing Civilization III. In
this episode we look at the Early game, which sets the stage for
everything that follows. Then we look at Revenue and Resources.
Links:

https://civilization.fandom.com/wiki/List_of_resources_in_Civ3
https://www.palain.com/gaming/civilization-iii/playing-civilization-iii-part-2/

This will probably be one I'll get a lot of comments on, but I've
looked at the marketing proposition of HPR in light of some of the
challenges we face. To prevent us dipping into the reserve queue and
seeing a slow but steady decline in both audience and hosts.. Maybe its
time to give HPR a bit of a makeover.