blob: bbe404324bce73f9ca9999dd2d6936cf90e5c184 [file] [log] [blame]
David K. Bainbridgebba65ff2018-01-19 09:26:09 -08001#!/usr/bin/env bash
2# Use this script to test if a given TCP host/port are available
3
4cmdname=$(basename $0)
5
6echoerr() { if [[ $QUIET -ne 1 ]]; then echo "$@" 1>&2; fi }
7
8usage()
9{
10 cat << USAGE >&2
11Usage:
12 $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
21USAGE
22 exit 1
23}
24
25wait_for()
26{
27 if [[ $TIMEOUT -gt 0 ]]; then
28 echoerr "$cmdname: waiting $TIMEOUT seconds for $HOST:$PORT"
29 else
30 echoerr "$cmdname: waiting for $HOST:$PORT without a timeout"
31 fi
32 start_ts=$(date +%s)
33 while :
34 do
35 if [[ $ISBUSY -eq 1 ]]; then
36 nc -z $HOST $PORT
37 result=$?
38 else
39 (echo > /dev/tcp/$HOST/$PORT) >/dev/null 2>&1
40 result=$?
41 fi
42 if [[ $result -eq 0 ]]; then
43 end_ts=$(date +%s)
44 echoerr "$cmdname: $HOST:$PORT is available after $((end_ts - start_ts)) seconds"
45 break
46 fi
47 sleep 1
48 done
49 return $result
50}
51
52wait_for_wrapper()
53{
54 # In order to support SIGINT during timeout: http://unix.stackexchange.com/a/57692
55 if [[ $QUIET -eq 1 ]]; then
56 timeout $BUSYTIMEFLAG $TIMEOUT $0 --quiet --child --host=$HOST --port=$PORT --timeout=$TIMEOUT &
57 else
58 timeout $BUSYTIMEFLAG $TIMEOUT $0 --child --host=$HOST --port=$PORT --timeout=$TIMEOUT &
59 fi
60 PID=$!
61 trap "kill -INT -$PID" INT
62 wait $PID
63 RESULT=$?
64 if [[ $RESULT -ne 0 ]]; then
65 echoerr "$cmdname: timeout occurred after waiting $TIMEOUT seconds for $HOST:$PORT"
66 fi
67 return $RESULT
68}
69
70# process arguments
71while [[ $# -gt 0 ]]
72do
73 case "$1" in
74 *:* )
75 hostport=(${1//:/ })
76 HOST=${hostport[0]}
77 PORT=${hostport[1]}
78 shift 1
79 ;;
80 --child)
81 CHILD=1
82 shift 1
83 ;;
84 -q | --quiet)
85 QUIET=1
86 shift 1
87 ;;
88 -s | --strict)
89 STRICT=1
90 shift 1
91 ;;
92 -h)
93 HOST="$2"
94 if [[ $HOST == "" ]]; then break; fi
95 shift 2
96 ;;
97 --host=*)
98 HOST="${1#*=}"
99 shift 1
100 ;;
101 -p)
102 PORT="$2"
103 if [[ $PORT == "" ]]; then break; fi
104 shift 2
105 ;;
106 --port=*)
107 PORT="${1#*=}"
108 shift 1
109 ;;
110 -t)
111 TIMEOUT="$2"
112 if [[ $TIMEOUT == "" ]]; then break; fi
113 shift 2
114 ;;
115 --timeout=*)
116 TIMEOUT="${1#*=}"
117 shift 1
118 ;;
119 --)
120 shift
121 CLI=("$@")
122 break
123 ;;
124 --help)
125 usage
126 ;;
127 *)
128 echoerr "Unknown argument: $1"
129 usage
130 ;;
131 esac
132done
133
134if [[ "$HOST" == "" || "$PORT" == "" ]]; then
135 echoerr "Error: you need to provide a host and port to test."
136 usage
137fi
138
139TIMEOUT=${TIMEOUT:-15}
140STRICT=${STRICT:-0}
141CHILD=${CHILD:-0}
142QUIET=${QUIET:-0}
143
144# check to see if timeout is from busybox?
145# check to see if timeout is from busybox?
146TIMEOUT_PATH=$(realpath $(which timeout))
147if [[ $TIMEOUT_PATH =~ "busybox" ]]; then
148 ISBUSY=1
149 BUSYTIMEFLAG="-t"
150else
151 ISBUSY=0
152 BUSYTIMEFLAG=""
153fi
154
155if [[ $CHILD -gt 0 ]]; then
156 wait_for
157 RESULT=$?
158 exit $RESULT
159else
160 if [[ $TIMEOUT -gt 0 ]]; then
161 wait_for_wrapper
162 RESULT=$?
163 else
164 wait_for
165 RESULT=$?
166 fi
167fi
168
169if [[ $CLI != "" ]]; then
170 if [[ $RESULT -ne 0 && $STRICT -eq 1 ]]; then
171 echoerr "$cmdname: strict mode, refusing to execute subprocess"
172 exit $RESULT
173 fi
174 exec "${CLI[@]}"
175else
176 exit $RESULT
177fi