unitc - a curl wrapper for configuring NGINX Unit

README.md

Moved to GitHub repo https://github.com/lcrilly/unitc

unitc

#!/bin/bash
# unitc - a curl wrapper for configuring NGINX Unit
# NGINX, Inc. (c) 2022

# Defaults
#
ERROR_LOG=/dev/null
REMOTE=0
QUIET=0
METHOD=PUT
SHOW_LOG=1
URI=""

while [ $# -gt 0 ]; do
	OPTION=$(echo $1 | tr '[a-z]' '[A-Z]')
	case $OPTION in
		"-H" | "--HELP")
			shift
			;;

		"-Q" | "--QUIET")
			QUIET=1
			shift
			;;

		"GET" | "PUT" | "POST" | "DELETE" | "INSERT")
			METHOD=$OPTION
			shift
			;;

		"HEAD" | "PATCH" | "PURGE" | "OPTIONS")
			echo "${0##*/}: ERROR: Invalid HTTP method ($OPTION)"
			exit 1
			;;

		*)
			if [ "${1:0:1}" = "/" ] || [ "${1:0:4}" = "http" ]; then
				URI=$1
				shift
			else
				echo "${0##*/}: ERROR: Invalid option ($1)"
				exit 1
			fi
			;;
	esac
done

if [ "$URI" = "" ]; then
	echo "${0##*/} - a curl wrapper for configuring NGINX Unit"
	echo ""
	echo "USAGE: ${0##*/} [--quiet] [HTTP method] URI"
	echo ""
	echo " URI is for the Unit configuration API, e.g. /config"
	echo " URI with protocol (e.g. http://...) can be used for remote configuration"
	echo " --quiet (-q) Will not monitor the error log after config changes"
	echo ""
	echo " • Environment variable \$UNIT_CTRL may specify remote host"
	echo " • Configuration JSON is read from stdin"
	echo " • Default HTTP method is PUT for config changes, else GET"
	echo " • Virtual method INSERT adds to beginning of array"
	echo " • Options can appear in any position, e.g. method after URI"
	echo " • The control socket is automatically detected for local installations"
	echo ""
	exit 1
fi

# Figure out if we're running on the Unit host, or remotely
#
if [ "$UNIT_CTRL" = "" ]; then
	if [ "${URI:0:4}" = "http" ]; then
		REMOTE=1
		UNIT_CTRL=$(echo "$URI" | cut -f1-3 -d/)
		URI=/$(echo "$URI" | cut -f4- -d/)
	fi
elif [ "${URI:0:1}" = "/" ]; then
	REMOTE=1
fi

if [ $REMOTE -eq 0 ]; then
	# Check if Unit is running, find the main process
	#
	PID=($(ps ax | grep unit:\ main | grep -v \ grep | awk '{print $1}'))
	if [ ${#PID[@]} -eq 0 ]; then
		echo "${0##*/}: ERROR: unitd not running"
		exit 1
	elif [ ${#PID[@]} -gt 1 ]; then
		echo "${0##*/}: ERROR: multiple unitd processes detected (${PID[@]})"
		exit 1
	fi

	# Read the significant unitd conifuration from cache file (or create it)
	#
	if [ -r /tmp/${0##*/}.$PID.env ]; then
		source /tmp/${0##*/}.$PID.env
	else
		# Check we have all the tools we need in $PATH
		#
		MISSING=$(hash curl ps grep tr sed tail sleep 2>&1 | cut -f4 -d: | tr -d '\n')
		if [ "$MISSING" != "" ]; then
			echo "${0##*/}: ERROR: cannot find$MISSING: please install or add to \$PATH"
			exit 1
		fi

		PARAMS=$(ps $PID | grep unitd | cut -f2- -dv | tr '[]' ' ' | cut -f4- -d ' ' | sed -e 's/ --/\n--/g')

		# Get control address
		#
		CTRL_ADDR=$(echo "$PARAMS" | grep '\--control' | cut -f2 -d' ')
		if [ "$CTRL_ADDR" = "" ]; then
			CTRL_ADDR=$(unitd --help | grep -A1 '\--control' | tail -1 |  cut -f2 -d\")
		fi

		# Prepare for network or Unix socket addressing
		#
		if [ $(echo $CTRL_ADDR | grep -c ^unix:) -eq 1 ]; then
			SOCK_FILE=$(echo $CTRL_ADDR | cut -f2- -d:)
			if [ -r $SOCK_FILE ]; then
				UNIT_CTRL="--unix-socket $SOCK_FILE _"
			else
				echo "${0##*/}: ERROR: cannot read unitd control socket: $SOCK_FILE"
				ls -l $SOCK_FILE
				exit 2
			fi
		else
			UNIT_CTRL="http://$CTRL_ADDR"
		fi

		# Get error log filename
		#
		ERROR_LOG=$(echo "$PARAMS" | grep '\--log' | cut -f2 -d' ')
		if [ "$ERROR_LOG" = "" ]; then
			ERROR_LOG=$(unitd --help | grep -A1 '\--log' | tail -1 | cut -f2 -d\")
		fi

		# Cache the discovery for this unit PID (and cleanup any old files)
		#
		rm /tmp/${0##*/}.* 2> /dev/null
		echo UNIT_CTRL=\"${UNIT_CTRL}\" > /tmp/${0##*/}.$PID.env
		echo ERROR_LOG=${ERROR_LOG} >> /tmp/${0##*/}.$PID.env
	fi
fi

# Test for jq
#
if hash jq 2> /dev/null; then
	PRETTY="jq"
else
	PRETTY="cat"
fi

# Get current length of error log before we make any changes
#
if [ -f $ERROR_LOG ] && [ -r $ERROR_LOG ]; then
	LOG_LEN=$(wc -l < $ERROR_LOG)
else
	QUIET=1
fi

# Adjust HTTP method and curl params based on presence of stdin payload
#
if [ -t 0 ]; then
	if [ "$METHOD" = "DELETE" ]; then
		curl -X $METHOD $UNIT_CTRL$URI 2> /tmp/${0##*/}.$$ | $PRETTY
	else
		SHOW_LOG=$(echo $URI | grep -c ^/control/)
		curl $UNIT_CTRL$URI 2> /tmp/${0##*/}.$$ | $PRETTY
	fi
else
	if [ "$METHOD" = "INSERT" ]; then
		if [ "$PRETTY" != "jq" ]; then
			echo "${0##*/}: ERROR: jq(1) is required to use INSERT method, install at <https://stedolan.github.io/jq/>"
			exit 1
		fi
		CURR_VAL=$(curl -s $UNIT_CTRL$URI)
		if [ "$(echo $CURR_VAL | jq -r type)" = "array" ]; then
			SUFFIX=$(cat)
			echo $CURR_VAL | jq ". |= [$SUFFIX] + ." | curl -X PUT --data-binary @- $UNIT_CTRL$URI 2> /tmp/${0##*/}.$$ | $PRETTY
		else
			echo "${0##*/}: ERROR: INSERT method must be used with an array"
			exit 3
		fi
	else
		echo "$(cat)" | curl -X $METHOD --data-binary @- $UNIT_CTRL$URI 2> /tmp/${0##*/}.$$ | $PRETTY
	fi
fi

CURL_STATUS=${PIPESTATUS[0]}
if [ $CURL_STATUS -ne 0 ]; then
	echo "${0##*/}: ERROR: curl(1) exited with an error ($CURL_STATUS)"
	if [ $CURL_STATUS -eq 7 ]; then
		echo "${0##*/}: Check that you have permission to access the Unit control socket, or try again with sudo(8)"
	else
		echo "${0##*/}: Trying to access $UNIT_CTRL$URI"
		cat /tmp/${0##*/}.$$ && rm /tmp/${0##*/}.$$
	fi
	exit 4
fi
rm /tmp/${0##*/}.$$ 2> /dev/null

if [ $SHOW_LOG -gt 0 ] && [ $QUIET -eq 0 ]; then
	echo -n "${0##*/}: Waiting for log..."
	sleep $SHOW_LOG
	echo ""
	sed -n $((LOG_LEN+1)),\$p $ERROR_LOG
fi

# vim: syntax=bash