bash-scripts

common.bash

#!/usr/bin/env bash

set -o errexit -o errtrace -o noclobber -o nounset -o pipefail

trap 'e=$?; if [ "$e" -ne "0" ]; then printf "LINE %s: exit %s <- %s%s\\n" "$BASH_LINENO" "$e" "${BASH_COMMAND}" "$(printf " <- %s" "${FUNCNAME[@]:-main}")" 1>&2; fi' EXIT


PROGNAME="${0##*/}"


log_verbose() {
	if [ "${verbose:-n}" == "y" ]; then
		log_info "$@"
	fi
}

log_debug() {
	(>&2 printf '%sDEBUG%s: %s\n' "$(tput setaf 7)" "$(tput sgr0)" "$@")
}

log_info() {
	(>&2 printf '%sINFO%s: %s\n' "$(tput setaf 2)" "$(tput sgr0)" "$@")
}

log_warn() {
	(>&2 printf '%sWARNING%s: %s\n' "$(tput setaf 3)" "$(tput sgr0)" "$@")
}

log_error() {
	(>&2 printf '%sERROR%s: %s\n' "$(tput setaf 1)" "$(tput sgr0)" "$@")
}

get_context() {
	local line
	local subroutine
	local filename
	line="$1"
	subroutine='call'
	if [ "$#" -eq "2" ]; then
		filename="$2"
	elif [ "$#" -eq "3" ]; then
		subroutine="$2"
		filename="$3"
	else
		log_error 'incorrect number of arguments!'
		exit 1
	fi
	printf '%s%s on line %d of %s:%s\n' "$(tput setaf 1)" "$subroutine" "$line" "$filename" "$(tput sgr0)"
	awk 'NR>L-4 && NR<L+4 { printf "%-5d%3s%s\n",NR,(NR==L?">>>":""),$0 }' L="$line" "$filename"
}

log_stack_trace() {
	local last_exit=$?
	local max_depth
	local depth
	if [ "$last_exit" -ne "0" ]; then
		depth=0
		max_depth="${1:-3}"
		while [ "$depth" -le "$max_depth" ] && caller "$depth" 1>/dev/null 2>&1 ; do
			log_error "$(get_context $(caller "$depth"))"
			depth+=1
		done
		log_error "$(printf '%s(%d) -> exit %d\n' $(caller 0 | awk '{ print $3,$1 }') "$last_exit")"
	fi
}

append_trap () {
	local trap_cmd
	local trap_sig
	local old_trap_cmd

	trap_cmd="$1"
	trap_sig="$2"

	old_trap_cmd="$(trap -p "$trap_sig" | sed -E -e "s/^[^'\"]*['\"]//" -e "s/['\"][[:space:]]*${trap_sig}\$//")"
	if [[ -n "$old_trap_cmd" ]]; then
		trap_cmd="$old_trap_cmd; $trap_cmd"
	fi
	trap "$trap_cmd" "$trap_sig"
}

trap 'log_stack_trace' EXIT

get_script_dir() {
	## resolve the directory of the given script
	# example:
	# 	get_script_dir "${BASH_SOURCE[0]}"
	SOURCE="${1}"
	#SOURCE="${BASH_SOURCE[0]}"
	while [ -h "$SOURCE" ]; do # resolve $SOURCE until the file is no longer a symlink
		SCRIPTDIR="$( cd -P "$( dirname "$SOURCE" )" && pwd )"
		SOURCE="$(readlink "$SOURCE")"
		[[ $SOURCE != /* ]] && SOURCE="$SCRIPTDIR/$SOURCE" # if $SOURCE was a relative symlink, we need to resolve it relative to the path where the symlink file was located
	done
	SCRIPTDIR="$( cd -P "$( dirname "$SOURCE" )" && pwd )"
	printf '%s\n' "${SCRIPTDIR}"
}

contains_value() {
	local value
	value="$1"
	shift
	for arg in "$@"; do
		if [ "$value" == "$arg" ]; then
			return 0
		fi
	done
	return 1
}

ltrim_ws() {
	local input
	local smallest_lws
	input="$(cat "${1:--}")"
	smallest_lws=$(printf '%s\n' "$input" | sed -e '/^[[:space:]]*$/d' -e 's/[^[:space:]].*$//' | sort | head -n 1 | wc -m)
	printf '%s\n' "$input" | cut -c ${smallest_lws}-
}

get_color() {
	local color
	case "$1" in
		bla*) color=0;;
		r*) color=1;;
		g*) color=2;;
		y*) color=3;;
		blu*) color=4;;
		m*|p*) color=5;;
		c*) color=6;;
		w*) color=7;;
		*)
			1>&2 printf '%s[ERROR]%s: unknown color name: %s\n' "$(tput setaf 1)" "$(tput sgr0)" "$1"
			return 1
			;;
	esac
	printf '%d\n' "$color"
}

hl() {
	local fg
	local bg
	local text

	if [ "$#" -lt "2"  ] || [ "$#" -gt "3" ]; then
		cat <<EOF | ltrim_ws 1>&2
		$(tput setaf 1)[ERROR]$(tput sgr0): incorrect # of arguments

		USAGE
			${FUNCNAME[@]:-main} FG_COLOR [BG_COLOR] TEXT

		EXAMPLE
			${FUNCNAME[@]:-main} red 'this text is red'
EOF
		return 1
	fi
	fg="$(tput setaf "$(get_color "$1")")"
	if [ "$#" -eq "3" ]; then
		bg="$(tput setab "$(get_color "$2")")"
		shift
	else
		bg=""
	fi
	text="$2"
	printf '%s%s%s\n' "${fg}${bg:-}" "$text" "$(tput sgr0)"
}

xml_format() { cat "${1:--}" | sed -E 's/^[[:space:]]+//' | tr -d '\n' | XMLLINT_INDENT=$'\t' xmllint --format - ; };

add_to_path() {
	local path_entries
	path_entries="$(printf '%s\n' "${PATH}" | tr ':' '\n')"
	for path_entry in "$@"; do
		if ! printf '%s\n' "${path_entries}" | grep --fixed-strings --line-regexp --quiet "${path_entry}"; then
			if [ ! -d "${path_entry}" ]; then
				printf '%sWARNING:%s Adding non-directory path to PATH: %s\n' "$(tput setaf 1)" "$(tput sgr0)" "${path_entry}" 1>&2
			else
				printf '%sINFO:%s Adding to PATH: %s\n' "$(tput setaf 2)" "$(tput sgr0)" "${path_entry}" 1>&2
			fi
			export PATH="${path_entry}:${PATH}"
		fi
	done
}

update_path() {
	local formula_name

	if [[ $# -eq 1 ]]; then
		formula_name="$1"
	else
		formula_name="all"
	fi

	if [ "$(uname)" == "Darwin" ]; then
		if [ "${formula_name}" == "all" ] || [ "${formula_name}" == "grep" ]; then
			add_to_path "$(brew --prefix 'grep')/libexec/gnubin"
		fi

		if [ "${formula_name}" == "all" ] || [ "${formula_name}" == "gnu-getopt" ]; then
			add_to_path "$(brew --prefix 'gnu-getopt')/bin"
		fi

		if [ "${formula_name}" == "all" ] || [ "${formula_name}" == "coreutils" ]; then
			add_to_path "$(brew --prefix 'coreutils')/libexec/gnubin"
		fi
	fi

	log_verbose "updated PATH: ${PATH}"
	printf '%s\n' "${PATH}"
}

get-latest.bash

#!/usr/bin/env bash

verbose="${verbose:-n}"

SOURCE="${BASH_SOURCE[0]}"
while [ -h "$SOURCE" ]; do # resolve $SOURCE until the file is no longer a symlink
	SCRIPTDIR="$( cd -P "$( dirname "$SOURCE" )" && pwd )"
	SOURCE="$(readlink "$SOURCE")"
	[[ $SOURCE != /* ]] && SOURCE="$SCRIPTDIR/$SOURCE" # if $SOURCE was a relative symlink, we need to resolve it relative to the path where the symlink file was located
done
SCRIPTDIR="$( cd -P "$( dirname "$SOURCE" )" && pwd )"

source "${SCRIPTDIR}/common.bash"
export PATH="$(update_path 'gnu-getopt')"

if command -v apt-get 1> /dev/null && ! command -v xmllint 1> /dev/null; then
	log_warn 'installing missing dependencies'
	DEBIAN_FRONTEND=noninteractive apt-get -q -y update && apt-get -q -y install \
		libxml2-utils
fi

find_xml_attr_vals() {
	OPTIONS=e:a:
	LONGOPTS=element-xpath:,attr-name:
	! PARSED=$(getopt --options=$OPTIONS --longoptions=$LONGOPTS --name "${0##*/}" -- "$@")
	if [[ ${PIPESTATUS[0]} -ne 0 ]]; then
		exit 2
	fi
	eval set -- "$PARSED"

	local element_xpath
	local attr_name
	local input
	local xml_data

	while true; do
		case "$1" in
			-e|--element-xpath)
				element_xpath="$2"
				shift 2
				;;
			-a|--attr-name)
				attr_name="$2"
				shift 2
				;;
			--)
				shift
				break
				;;
			*)
				echo "Programming error"
				exit 2
				;;
		esac
	done

	if [ "${element_xpath:-}" == "" ]; then
		log_error "find_xml_attr_vals --element-xpath option is requred"
		exit 123
	fi
	if [ "${attr_name:-}" == "" ]; then
		log_error "find_xml_attr_vals --attr-name option is requred"
		exit 123
	fi
	if [[ $# -ne 1 ]]; then
		log_error "find_xml_attr_vals accepts one positional argument for the xml input, but got $#"
		exit 123
	fi
	[ -f "$1" ] && input="$1" || input="-"
	xml_data="$(cat "${input}" | sed 's/xmlns[[:space:]]*=/ignore=/')"

	local num_matched
	num_matched="$(printf '%s' "${xml_data}" | \
		xmllint --xpath "count(${element_xpath}/@${attr_name})" - )"
	log_verbose "found ${num_matched} attrs matching '${element_xpath}/@${attr_name}'"
	local attr_val
	for i in $(seq 1 "${num_matched}"); do
		attr_val="$(printf '%s' "${xml_data}" | \
			xmllint --xpath "${element_xpath}[${i}]/@${attr_name}" - | \
			sed -E 's/.*"(.*)".*/\1/')"
		#log_verbose "	${element_xpath}[${i}]/@${attr_name} = ${attr_val}"
		printf '%s\n' "${attr_val}"
	done
}

get_versions() {
	local versions_url
	local versions_xml
	local versions

	versions_url="$1"
	log_verbose "fetching latest versions from ${versions_url}"
	versions_xml="$(curl -s "${versions_url}" | sed -n '2,$p')"

	versions=()
	while IFS=	read -r; do
		versions+=("${REPLY}")
	done < <(printf '%s' "${versions_xml}" | \
		find_xml_attr_vals --element-xpath "//a" --attr-name "href" - | \
		grep -Ev '\-|\.\.' | \
		sed 's/\/$//' | \
		sort -rV)
	log_verbose "${#versions[@]} parsed versions:$(printf '\n\t%s' "${versions[@]}")"
	printf '%s\n' "${versions[@]}"
}

get_latest_version() {
	local versions_url
	local major_version
	local versions
	local latest_version

	versions_url="$1"
	if [[ $# -eq 2 ]]; then
		major_version="$2"
	fi

	versions="$(get_versions "${versions_url}" | grep -E "^${major_version:-[0-9]+}\." | sort -rV)" || \
		(log_error "no versions ${major_version:+matching ${major_version}.X.X }found"; exit 2)
	latest_version="$(printf '%s' "${versions}" | head -n 1)"
	log_verbose "latest version: ${latest_version}"
	printf '%s' "${latest_version}"
}

get_latest_version "$@"