Common bash shared/helper functions.
#!/usr/bin/env bash
# ##################################################
# Shared bash functions used by my bash scripts.
#
# VERSION 1.4.0
#
# HISTORY
#
# * 2015-01-02 - v1.0.0 - First Creation
# * 2015-04-16 - v1.2.0 - Added 'checkDependencies' and 'pauseScript'
# * 2016-01-10 - v1.3.0 - Added 'join' function
# * 2016-01-11 - v1.4.9 - Added 'httpStatus' function
#
# ##################################################
# Traps
# ------------------------------------------------------
# These functions are for use with different trap scenarios
# ------------------------------------------------------
# Non destructive exit for when script exits naturally.
# Usage: Add this function at the end of every script
function safeExit() {
# Delete temp files, if any
if is_dir "${tmpDir}"; then
rm -r "${tmpDir}"
fi
trap - INT TERM EXIT
exit
}
# readFile
# ------------------------------------------------------
# Function to read a line from a file.
#
# Most often used to read the config files saved in my etc directory.
# Outputs each line in a variable named $result
# ------------------------------------------------------
function readFile() {
unset "${result}"
while read result
do
echo "${result}"
done < "$1"
}
# Escape a string
# ------------------------------------------------------
# usage: var=$(escape "String")
# ------------------------------------------------------
escape() { echo "${@}" | sed 's/[]\.|$(){}?+*^]/\\&/g'; }
# needSudo
# ------------------------------------------------------
# If a script needs sudo access, call this function which
# requests sudo access and then keeps it alive.
# ------------------------------------------------------
function needSudo() {
# Update existing sudo time stamp if set, otherwise do nothing.
sudo -v
while true; do sudo -n true; sleep 60; kill -0 "$$" || exit; done 2>/dev/null &
}
# convertsecs
# ------------------------------------------------------
# Convert Seconds to human readable time
#
# To use this, pass a number (seconds) into the function as this:
# print "$(convertsecs $TOTALTIME)"
#
# To compute the time it takes a script to run use tag the start and end times with
# STARTTIME=$(date +"%s")
# ENDTIME=$(date +"%s")
# TOTALTIME=$(($ENDTIME-$STARTTIME))
# ------------------------------------------------------
function convertsecs() {
((h=${1}/3600))
((m=(${1}%3600)/60))
((s=${1}%60))
printf "%02d:%02d:%02d\n" $h $m $s
}
function pushover() {
# pushover
# ------------------------------------------------------
# Sends notifications view Pushover
# Requires a file named 'pushover.cfg' be placed in '../etc/'
#
# Usage: pushover "Title Goes Here" "Message Goes Here"
#
# Credit: http://ryonsherman.blogspot.com/2012/10/shell-script-to-send-pushover.html
# ------------------------------------------------------
# Check for config file containing API Keys
if [ ! -f "${SOURCEPATH}/../etc/pushover.cfg" ]; then
error "Please locate the pushover.cfg to send notifications to Pushover."
else
# Grab variables from the config file
source "${SOURCEPATH}/../etc/pushover.cfg"
# Send to Pushover
PUSHOVERURL="https://api.pushover.net/1/messages.json"
API_KEY="${PUSHOVER_API_KEY}"
USER_KEY="${PUSHOVER_USER_KEY}"
DEVICE=""
TITLE="${1}"
MESSAGE="${2}"
curl \
-F "token=${API_KEY}" \
-F "user=${USER_KEY}" \
-F "device=${DEVICE}" \
-F "title=${TITLE}" \
-F "message=${MESSAGE}" \
"${PUSHOVERURL}" > /dev/null 2>&1
fi
}
# Join
# ----------------------------------------------
# This function joins items together with a user specified separator
# Taken whole cloth from: http://stackoverflow.com/questions/1527049/bash-join-elements-of-an-array
#
# Usage:
# join , a "b c" d #a,b c,d
# join / var local tmp #var/local/tmp
# join , "${FOO[@]}" #a,b,c
# ----------------------------------------------
function join() { local IFS="${1}"; shift; echo "${*}"; }
# File Checks
# ------------------------------------------------------
# A series of functions which make checks against the filesystem. For
# use in if/then statements.
#
# Usage:
# if is_file "file"; then
# ...
# fi
# ------------------------------------------------------
function is_exists() {
if [[ -e "$1" ]]; then
return 0
fi
return 1
}
function is_not_exists() {
if [[ ! -e "$1" ]]; then
return 0
fi
return 1
}
function is_file() {
if [[ -f "$1" ]]; then
return 0
fi
return 1
}
function is_not_file() {
if [[ ! -f "$1" ]]; then
return 0
fi
return 1
}
function is_dir() {
if [[ -d "$1" ]]; then
return 0
fi
return 1
}
function is_not_dir() {
if [[ ! -d "$1" ]]; then
return 0
fi
return 1
}
function is_symlink() {
if [[ -L "$1" ]]; then
return 0
fi
return 1
}
function is_not_symlink() {
if [[ ! -L "$1" ]]; then
return 0
fi
return 1
}
function is_empty() {
if [[ -z "$1" ]]; then
return 0
fi
return 1
}
function is_not_empty() {
if [[ -n "$1" ]]; then
return 0
fi
return 1
}
# Test whether a command exists
# ------------------------------------------------------
# Usage:
# if type_exists 'git'; then
# some action
# else
# some other action
# fi
# ------------------------------------------------------
function type_exists() {
if [ "$(type -P "$1")" ]; then
return 0
fi
return 1
}
function type_not_exists() {
if [ ! "$(type -P "$1")" ]; then
return 0
fi
return 1
}
# Test which OS the user runs
# $1 = OS to test
# Usage: if is_os 'darwin'; then
function is_os() {
if [[ "${OSTYPE}" == $1* ]]; then
return 0
fi
return 1
}
# SEEKING CONFIRMATION
# ------------------------------------------------------
# Asks questions of a user and then does something with the answer.
# y/n are the only possible answers.
#
# USAGE:
# seek_confirmation "Ask a question"
# if is_confirmed; then
# some action
# else
# some other action
# fi
#
# Credt: https://github.com/kevva/dotfiles
# ------------------------------------------------------
# Ask the question
function seek_confirmation() {
# echo ""
input "$@"
if "${force}"; then
notice "Forcing confirmation with '--force' flag set"
else
read -p " (y/n) " -n 1
echo ""
fi
}
# Test whether the result of an 'ask' is a confirmation
function is_confirmed() {
if "${force}"; then
return 0
else
if [[ "${REPLY}" =~ ^[Yy]$ ]]; then
return 0
fi
return 1
fi
}
function is_not_confirmed() {
if "${force}"; then
return 1
else
if [[ "${REPLY}" =~ ^[Nn]$ ]]; then
return 0
fi
return 1
fi
}
# Skip something
# ------------------------------------------------------
# Offer the user a chance to skip something.
# Credit: https://github.com/cowboy/dotfiles
# ------------------------------------------------------
function skip() {
REPLY=noskip
read -t 5 -n 1 -s -p "${bold}To skip, press ${underline}X${reset}${bold} within 5 seconds.${reset}"
if [[ "$REPLY" =~ ^[Xx]$ ]]; then
notice " Skipping!"
return 0
else
notice " Continuing..."
return 1
fi
}
# unmountDrive
# ------------------------------------------------------
# If an AFP drive is mounted as part of a script, this
# will unmount the volume. This will only work on Macs.
# ------------------------------------------------------
function unmountDrive() {
if [ -d "$1" ]; then
diskutil unmount "$1"
fi
}
# help
# ------------------------------------------------------
# Prints help for a script when invoked from the command
# line. Typically via '-h'. If additional flags or help
# text is available in the script they will be printed
# in the '$usage' variable.
# ------------------------------------------------------
function help () {
echo "" 1>&2
input " $@" 1>&2
if [ -n "${usage}" ]; then # print usage information if available
echo " ${usage}" 1>&2
fi
echo "" 1>&2
exit 1
}
# Dependencies
# -----------------------------------
# Arrays containing package dependencies needed to execute this script.
# The script will fail if dependencies are not installed. For Mac users,
# most dependencies can be installed automatically using the package
# manager 'Homebrew'.
# Usage in script: $ homebrewDependencies=(package1 package2)
# -----------------------------------
function checkDependencies() {
saveIFS=$IFS
IFS=$' \n\t'
if [ -n "${homebrewDependencies}" ]; then
LISTINSTALLED="brew list"
INSTALLCOMMAND="brew install"
RECIPES=("${homebrewDependencies[@]}")
# Invoke functions from setupScriptFunctions.sh
hasHomebrew
doInstall
fi
if [ -n "$caskDependencies" ]; then
LISTINSTALLED="brew cask list"
INSTALLCOMMAND="brew cask install --appdir=/Applications"
RECIPES=("${caskDependencies[@]}")
# Invoke functions from setupScriptFunctions.sh
hasHomebrew
hasCasks
doInstall
fi
if [ -n "$gemDependencies" ]; then
LISTINSTALLED="gem list | awk '{print $1}'"
INSTALLCOMMAND="gem install"
RECIPES=("${gemDependencies[@]}")
# Invoke functions from setupScriptFunctions.sh
doInstall
fi
IFS=$saveIFS
}
function pauseScript() {
# A simple function used to pause a script at any point and
# only continue on user input
seek_confirmation "Ready to continue?"
if is_confirmed; then
info "Continuing"
else
warning "Exiting Script."
safeExit
fi
}
function in_array() {
# Determine if a value is in an array.
# Usage: if in_array "VALUE" "${ARRAY[@]}"; then ...
local value="$1"; shift
for arrayItem in "$@"; do
[[ "${arrayItem}" == "${value}" ]] && return 0
done
return 1
}
# Text Transformations
# -----------------------------------
# Transform text using these functions.
# Adapted from https://github.com/jmcantrell/bashful
# -----------------------------------
lower() {
# Convert stdin to lowercase.
# usage: text=$(lower <<<"$1")
# echo "MAKETHISLOWERCASE" | lower
tr '[:upper:]' '[:lower:]'
}
upper() {
# Convert stdin to uppercase.
# usage: text=$(upper <<<"$1")
# echo "MAKETHISUPPERCASE" | upper
tr '[:lower:]' '[:upper:]'
}
ltrim() {
# Removes all leading whitespace (from the left).
local char=${1:-[:space:]}
sed "s%^[${char//%/\\%}]*%%"
}
rtrim() {
# Removes all trailing whitespace (from the right).
local char=${1:-[:space:]}
sed "s%[${char//%/\\%}]*$%%"
}
trim() {
# Removes all leading/trailing whitespace
# Usage examples:
# echo " foo bar baz " | trim #==> "foo bar baz"
ltrim "$1" | rtrim "$1"
}
squeeze() {
# Removes leading/trailing whitespace and condenses all other consecutive
# whitespace into a single space.
#
# Usage examples:
# echo " foo bar baz " | squeeze #==> "foo bar baz"
local char=${1:-[[:space:]]}
sed "s%\(${char//%/\\%}\)\+%\1%g" | trim "$char"
}
squeeze_lines() {
# <doc:squeeze_lines> {{{
#
# Removes all leading/trailing blank lines and condenses all other
# consecutive blank lines into a single blank line.
#
# </doc:squeeze_lines> }}}
sed '/^[[:space:]]\+$/s/.*//g' | cat -s | trim_lines
}
progressBar() {
# progressBar
# -----------------------------------
# Prints a progress bar within a for/while loop.
# To use this function you must pass the total number of
# times the loop will run to the function.
#
# usage:
# for number in $(seq 0 100); do
# sleep 1
# progressBar 100
# done
# -----------------------------------
if [[ "${quiet}" = "true" ]] || [ "${quiet}" == "1" ]; then
return
fi
local width
width=30
bar_char="#"
# Don't run this function when scripts are running in verbose mode
if ${verbose}; then return; fi
# Reset the count
if [ -z "${progressBarProgress}" ]; then
progressBarProgress=0
fi
# Do nothing if the output is not a terminal
if [ ! -t 1 ]; then
echo "Output is not a terminal" 1>&2
return
fi
# Hide the cursor
tput civis
trap 'tput cnorm; exit 1' SIGINT
if [ ! "${progressBarProgress}" -eq $(( $1 - 1 )) ]; then
# Compute the percentage.
perc=$(( progressBarProgress * 100 / $1 ))
# Compute the number of blocks to represent the percentage.
num=$(( progressBarProgress * width / $1 ))
# Create the progress bar string.
bar=
if [ ${num} -gt 0 ]; then
bar=$(printf "%0.s${bar_char}" $(seq 1 ${num}))
fi
# Print the progress bar.
progressBarLine=$(printf "%s [%-${width}s] (%d%%)" "Running Process" "${bar}" "${perc}")
echo -en "${progressBarLine}\r"
progressBarProgress=$(( progressBarProgress + 1 ))
else
# Clear the progress bar when complete
echo -ne "${width}%\033[0K\r"
unset progressBarProgress
fi
tput cnorm
}
htmlDecode() {
# Decode HTML characters with sed
# Usage: htmlDecode <string>
echo "${1}" | sed -f "${SOURCEPATH}/htmlDecode.sed"
}
htmlEncode() {
# Encode HTML characters with sed
# Usage: htmlEncode <string>
echo "${1}" | sed -f "${SOURCEPATH}/htmlEncode.sed"
}
urlencode() {
# URL encoding/decoding from: https://gist.github.com/cdown/1163649
# Usage: urlencode <string>
local length="${#1}"
for (( i = 0; i < length; i++ )); do
local c="${1:i:1}"
case $c in
[a-zA-Z0-9.~_-]) printf "%s" "$c" ;;
*) printf '%%%02X' "'$c"
esac
done
}
urldecode() {
# Usage: urldecode <string>
local url_encoded="${1//+/ }"
printf '%b' "${url_encoded//%/\x}"
}
parse_yaml() {
# Function to parse YAML files and add values to variables. Send it to a temp file and source it
# https://gist.github.com/DinoChiesa/3e3c3866b51290f31243 which is derived from
# https://gist.github.com/epiloque/8cf512c6d64641bde388
#
# Usage:
# $ parse_yaml sample.yml > /some/tempfile
#
# parse_yaml accepts a prefix argument so that imported settings all have a common prefix
# (which will reduce the risk of name-space collisions).
#
# $ parse_yaml sample.yml "CONF_"
local prefix=$2
local s
local w
local fs
s='[[:space:]]*'
w='[a-zA-Z0-9_]*'
fs="$(echo @|tr @ '\034')"
sed -ne "s|^\($s\)\($w\)$s:$s\"\(.*\)\"$s\$|\1$fs\2$fs\3|p" \
-e "s|^\($s\)\($w\)$s[:-]$s\(.*\)$s\$|\1$fs\2$fs\3|p" "$1" |
awk -F"$fs" '{
indent = length($1)/2;
if (length($2) == 0) { conj[indent]="+";} else {conj[indent]="";}
vname[indent] = $2;
for (i in vname) {if (i > indent) {delete vname[i]}}
if (length($3) > 0) {
vn=""; for (i=0; i<indent; i++) {vn=(vn)(vname[i])("_")}
printf("%s%s%s%s=(\"%s\")\n", "'"$prefix"'",vn, $2, conj[indent-1],$3);
}
}' | sed 's/_=/+=/g'
}
httpStatus() {
# -----------------------------------
# Shamelessly taken from: https://gist.github.com/rsvp/1171304
#
# Usage: httpStatus URL [timeout] [--code or --status] [see 4.]
# ^message with code (default)
# ^code (numeric only)
# ^in secs (default: 3)
# ^URL without "http://" prefix works fine.
#
# 4. curl options: e.g. use -L to follow redirects.
#
# Dependencies: curl
#
# Example: $ httpStatus bit.ly
# 301 Redirection: Moved Permanently
#
# Example: $ httpStatus www.google.com 100 -c
# 200
#
# -----------------------------------
local curlops
local arg4
local arg5
local arg6
local arg7
local flag
local timeout
local url
saveIFS=${IFS}
IFS=$' \n\t'
url=${1}
timeout=${2:-'3'}
# ^in seconds
flag=${3:-'--status'}
# curl options, e.g. -L to follow redirects
arg4=${4:-''}
arg5=${5:-''}
arg6=${6:-''}
arg7=${7:-''}
curlops="${arg4} ${arg5} ${arg6} ${arg7}"
# __________ get the CODE which is numeric:
code=`echo $(curl --write-out %{http_code} --silent --connect-timeout ${timeout} \
--no-keepalive ${curlops} --output /dev/null ${url})`
# __________ get the STATUS (from code) which is human interpretable:
case $code in
000) status="Not responding within ${timeout} seconds" ;;
100) status="Informational: Continue" ;;
101) status="Informational: Switching Protocols" ;;
200) status="Successful: OK within ${timeout} seconds" ;;
201) status="Successful: Created" ;;
202) status="Successful: Accepted" ;;
203) status="Successful: Non-Authoritative Information" ;;
204) status="Successful: No Content" ;;
205) status="Successful: Reset Content" ;;
206) status="Successful: Partial Content" ;;
300) status="Redirection: Multiple Choices" ;;
301) status="Redirection: Moved Permanently" ;;
302) status="Redirection: Found residing temporarily under different URI" ;;
303) status="Redirection: See Other" ;;
304) status="Redirection: Not Modified" ;;
305) status="Redirection: Use Proxy" ;;
306) status="Redirection: status not defined" ;;
307) status="Redirection: Temporary Redirect" ;;
400) status="Client Error: Bad Request" ;;
401) status="Client Error: Unauthorized" ;;
402) status="Client Error: Payment Required" ;;
403) status="Client Error: Forbidden" ;;
404) status="Client Error: Not Found" ;;
405) status="Client Error: Method Not Allowed" ;;
406) status="Client Error: Not Acceptable" ;;
407) status="Client Error: Proxy Authentication Required" ;;
408) status="Client Error: Request Timeout within ${timeout} seconds" ;;
409) status="Client Error: Conflict" ;;
410) status="Client Error: Gone" ;;
411) status="Client Error: Length Required" ;;
412) status="Client Error: Precondition Failed" ;;
413) status="Client Error: Request Entity Too Large" ;;
414) status="Client Error: Request-URI Too Long" ;;
415) status="Client Error: Unsupported Media Type" ;;
416) status="Client Error: Requested Range Not Satisfiable" ;;
417) status="Client Error: Expectation Failed" ;;
500) status="Server Error: Internal Server Error" ;;
501) status="Server Error: Not Implemented" ;;
502) status="Server Error: Bad Gateway" ;;
503) status="Server Error: Service Unavailable" ;;
504) status="Server Error: Gateway Timeout within ${timeout} seconds" ;;
505) status="Server Error: HTTP Version Not Supported" ;;
*) echo " !! httpstatus: status not defined." && safeExit ;;
esac
# _______________ MAIN
case ${flag} in
--status) echo "${code} ${status}" ;;
-s) echo "${code} ${status}" ;;
--code) echo "${code}" ;;
-c) echo "${code}" ;;
*) echo " !! httpstatus: bad flag" && safeExit;;
esac
IFS="${saveIFS}"
}
function makeCSV() {
# Creates a new CSV file if one does not already exist.
# Takes passed arguments and writes them as a header line to the CSV
# Usage 'makeCSV column1 column2 column3'
# Set the location and name of the CSV File
if [ -z "${csvLocation}" ]; then
csvLocation="${HOME}/Desktop"
fi
if [ -z "${csvName}" ]; then
csvName="$(LC_ALL=C date +%Y-%m-%d)-${FUNCNAME[1]}.csv"
fi
csvFile="${csvLocation}/${csvName}"
# Overwrite existing file? If not overwritten, new content is added
# to the bottom of the existing file
if [ -f "${csvFile}" ]; then
seek_confirmation "${csvFile} already exists. Overwrite?"
if is_confirmed; then
rm "${csvFile}"
writeCSV "$@"
fi
fi
}
function writeCSV() {
# Takes passed arguments and writes them as a comma separated line
# Usage 'writeCSV column1 column2 column3'
csvInput=($@)
saveIFS=$IFS
IFS=','
echo "${csvInput[*]}" >> "${csvFile}"
IFS=$saveIFS
}
function json2yaml() {
# convert json files to yaml using python and PyYAML
python -c 'import sys, yaml, json; yaml.safe_dump(json.load(sys.stdin), sys.stdout, default_flow_style=False)' < "$1"
}
function yaml2json() {
# convert yaml files to json using python and PyYAML
python -c 'import sys, yaml, json; json.dump(yaml.load(sys.stdin), sys.stdout, indent=4)' < "$1"
}