| 1 | #!/usr/bin/env bash |
| 2 | # Use this script to test if a given TCP host/port are available |
| 3 | |
| 4 | WAITFORIT_cmdname=${0##*/} |
| 5 | |
| 6 | echoerr() { if [[ $WAITFORIT_QUIET -ne 1 ]]; then echo "$@" 1>&2; fi } |
| 7 | |
| 8 | usage() |
| 9 | { |
| 10 | cat << USAGE >&2 |
| 11 | Usage: |
| 12 | $WAITFORIT_cmdname host:port [-s] [-t timeout] [-- command args] |
| 13 | -h HOST | --host=HOST Host or IP under test |
| 14 | -p PORT | --port=PORT TCP port under test |
| 15 | Alternatively, you specify the host and port as host:port |
| 16 | -s | --strict Only execute subcommand if the test succeeds |
| 17 | -q | --quiet Don't output any status messages |
| 18 | -t TIMEOUT | --timeout=TIMEOUT |
| 19 | Timeout in seconds, zero for no timeout |
| 20 | -- COMMAND ARGS Execute command with args after the test finishes |
| 21 | USAGE |
| 22 | exit 1 |
| 23 | } |
| 24 | |
| 25 | wait_for() |
| 26 | { |
| 27 | if [[ $WAITFORIT_TIMEOUT -gt 0 ]]; then |
| 28 | echoerr "$WAITFORIT_cmdname: waiting $WAITFORIT_TIMEOUT seconds for $WAITFORIT_HOST:$WAITFORIT_PORT" |
| 29 | else |
| 30 | echoerr "$WAITFORIT_cmdname: waiting for $WAITFORIT_HOST:$WAITFORIT_PORT without a timeout" |
| 31 | fi |
| 32 | WAITFORIT_start_ts=$(date +%s) |
| 33 | while : |
| 34 | do |
| 35 | if [[ $WAITFORIT_ISBUSY -eq 1 ]]; then |
| 36 | nc -z $WAITFORIT_HOST $WAITFORIT_PORT |
| 37 | WAITFORIT_result=$? |
| 38 | else |
| 39 | (echo -n > /dev/tcp/$WAITFORIT_HOST/$WAITFORIT_PORT) >/dev/null 2>&1 |
| 40 | WAITFORIT_result=$? |
| 41 | fi |
| 42 | if [[ $WAITFORIT_result -eq 0 ]]; then |
| 43 | WAITFORIT_end_ts=$(date +%s) |
| 44 | echoerr "$WAITFORIT_cmdname: $WAITFORIT_HOST:$WAITFORIT_PORT is available after $((WAITFORIT_end_ts - WAITFORIT_start_ts)) seconds" |
| 45 | break |
| 46 | fi |
| 47 | sleep 1 |
| 48 | done |
| 49 | return $WAITFORIT_result |
| 50 | } |
| 51 | |
| 52 | wait_for_wrapper() |
| 53 | { |
| 54 | # In order to support SIGINT during timeout: http://unix.stackexchange.com/a/57692 |
| 55 | if [[ $WAITFORIT_QUIET -eq 1 ]]; then |
| 56 | timeout $WAITFORIT_BUSYTIMEFLAG $WAITFORIT_TIMEOUT $0 --quiet --child --host=$WAITFORIT_HOST --port=$WAITFORIT_PORT --timeout=$WAITFORIT_TIMEOUT & |
| 57 | else |
| 58 | timeout $WAITFORIT_BUSYTIMEFLAG $WAITFORIT_TIMEOUT $0 --child --host=$WAITFORIT_HOST --port=$WAITFORIT_PORT --timeout=$WAITFORIT_TIMEOUT & |
| 59 | fi |
| 60 | WAITFORIT_PID=$! |
| 61 | trap "kill -INT -$WAITFORIT_PID" INT |
| 62 | wait $WAITFORIT_PID |
| 63 | WAITFORIT_RESULT=$? |
| 64 | if [[ $WAITFORIT_RESULT -ne 0 ]]; then |
| 65 | echoerr "$WAITFORIT_cmdname: timeout occurred after waiting $WAITFORIT_TIMEOUT seconds for $WAITFORIT_HOST:$WAITFORIT_PORT" |
| 66 | fi |
| 67 | return $WAITFORIT_RESULT |
| 68 | } |
| 69 | |
| 70 | # process arguments |
| 71 | while [[ $# -gt 0 ]] |
| 72 | do |
| 73 | case "$1" in |
| 74 | *:* ) |
| 75 | WAITFORIT_hostport=(${1//:/ }) |
| 76 | WAITFORIT_HOST=${WAITFORIT_hostport[0]} |
| 77 | WAITFORIT_PORT=${WAITFORIT_hostport[1]} |
| 78 | shift 1 |
| 79 | ;; |
| 80 | --child) |
| 81 | WAITFORIT_CHILD=1 |
| 82 | shift 1 |
| 83 | ;; |
| 84 | -q | --quiet) |
| 85 | WAITFORIT_QUIET=1 |
| 86 | shift 1 |
| 87 | ;; |
| 88 | -s | --strict) |
| 89 | WAITFORIT_STRICT=1 |
| 90 | shift 1 |
| 91 | ;; |
| 92 | -h) |
| 93 | WAITFORIT_HOST="$2" |
| 94 | if [[ $WAITFORIT_HOST == "" ]]; then break; fi |
| 95 | shift 2 |
| 96 | ;; |
| 97 | --host=*) |
| 98 | WAITFORIT_HOST="${1#*=}" |
| 99 | shift 1 |
| 100 | ;; |
| 101 | -p) |
| 102 | WAITFORIT_PORT="$2" |
| 103 | if [[ $WAITFORIT_PORT == "" ]]; then break; fi |
| 104 | shift 2 |
| 105 | ;; |
| 106 | --port=*) |
| 107 | WAITFORIT_PORT="${1#*=}" |
| 108 | shift 1 |
| 109 | ;; |
| 110 | -t) |
| 111 | WAITFORIT_TIMEOUT="$2" |
| 112 | if [[ $WAITFORIT_TIMEOUT == "" ]]; then break; fi |
| 113 | shift 2 |
| 114 | ;; |
| 115 | --timeout=*) |
| 116 | WAITFORIT_TIMEOUT="${1#*=}" |
| 117 | shift 1 |
| 118 | ;; |
| 119 | --) |
| 120 | shift |
| 121 | WAITFORIT_CLI=("$@") |
| 122 | break |
| 123 | ;; |
| 124 | --help) |
| 125 | usage |
| 126 | ;; |
| 127 | *) |
| 128 | echoerr "Unknown argument: $1" |
| 129 | usage |
| 130 | ;; |
| 131 | esac |
| 132 | done |
| 133 | |
| 134 | if [[ "$WAITFORIT_HOST" == "" || "$WAITFORIT_PORT" == "" ]]; then |
| 135 | echoerr "Error: you need to provide a host and port to test." |
| 136 | usage |
| 137 | fi |
| 138 | |
| 139 | WAITFORIT_TIMEOUT=${WAITFORIT_TIMEOUT:-15} |
| 140 | WAITFORIT_STRICT=${WAITFORIT_STRICT:-0} |
| 141 | WAITFORIT_CHILD=${WAITFORIT_CHILD:-0} |
| 142 | WAITFORIT_QUIET=${WAITFORIT_QUIET:-0} |
| 143 | |
| 144 | # Check to see if timeout is from busybox? |
| 145 | WAITFORIT_TIMEOUT_PATH=$(type -p timeout) |
| 146 | WAITFORIT_TIMEOUT_PATH=$(realpath $WAITFORIT_TIMEOUT_PATH 2>/dev/null || readlink -f $WAITFORIT_TIMEOUT_PATH) |
| 147 | |
| 148 | WAITFORIT_BUSYTIMEFLAG="" |
| 149 | if [[ $WAITFORIT_TIMEOUT_PATH =~ "busybox" ]]; then |
| 150 | WAITFORIT_ISBUSY=1 |
| 151 | # Check if busybox timeout uses -t flag |
| 152 | # (recent Alpine versions don't support -t anymore) |
| 153 | if timeout &>/dev/stdout | grep -q -e '-t '; then |
| 154 | WAITFORIT_BUSYTIMEFLAG="-t" |
| 155 | fi |
| 156 | else |
| 157 | WAITFORIT_ISBUSY=0 |
| 158 | fi |
| 159 | |
| 160 | if [[ $WAITFORIT_CHILD -gt 0 ]]; then |
| 161 | wait_for |
| 162 | WAITFORIT_RESULT=$? |
| 163 | exit $WAITFORIT_RESULT |
| 164 | else |
| 165 | if [[ $WAITFORIT_TIMEOUT -gt 0 ]]; then |
| 166 | wait_for_wrapper |
| 167 | WAITFORIT_RESULT=$? |
| 168 | else |
| 169 | wait_for |
| 170 | WAITFORIT_RESULT=$? |
| 171 | fi |
| 172 | fi |
| 173 | |
| 174 | if [[ $WAITFORIT_CLI != "" ]]; then |
| 175 | if [[ $WAITFORIT_RESULT -ne 0 && $WAITFORIT_STRICT -eq 1 ]]; then |
| 176 | echoerr "$WAITFORIT_cmdname: strict mode, refusing to execute subprocess" |
| 177 | exit $WAITFORIT_RESULT |
| 178 | fi |
| 179 | exec "${WAITFORIT_CLI[@]}" |
| 180 | else |
| 181 | exit $WAITFORIT_RESULT |
| 182 | fi |