Część, chce by kontener zbudowany na aplikacji spring-boota komunikował się z kontenerem MySql. Główny problem polega na tym, że MySql nie jest jeszcze gotowe gdy kontener z aplikacja chce sie do niej pałączyć.
docker-compose.yml
version: "3.3"
services:
api:
build: .
container_name: api
ports:
- "8080:8080"
depends_on:
- db
db:
container_name: db
image: mysql
ports:
- 3306
environment:
MYSQL_ALLOW_EMPTY_PASSWORD: "yes"
MYSQL_USER: "user"
MYSQL_PASSWORD: "password"
MYSQL_DATABASE: "db"
Dockerfile
FROM openjdk:8u191-jdk-alpine3.9
ADD target/app-0.0.1-SNAPSHOT.jar .
EXPOSE 8080
ENTRYPOINT ["./wait-for-it.sh", "db:3306", "--", "java", "-jar", "app-0.0.1-SNAPSHOT.jar"]
application.properties
spring.datasource.url=jdbc:mysql://db:3306/db?createDatabaseIfNotExist=true&useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC
spring.datasource.username=user
spring.datasource.password=password
spring.jpa.hibernate.ddl-auto=update
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
wait-for-it.sh
# Use this script to test if a given TCP host/port are available
WAITFORIT_cmdname=${0##*/}
echoerr() { if [[ $WAITFORIT_QUIET -ne 1 ]]; then echo "$@" 1>&2; fi }
usage()
{
cat << USAGE >&2
Usage:
$WAITFORIT_cmdname host:port [-s] [-t timeout] [-- command args]
-h HOST | --host=HOST Host or IP under test
-p PORT | --port=PORT TCP port under test
Alternatively, you specify the host and port as host:port
-s | --strict Only execute subcommand if the test succeeds
-q | --quiet Don't output any status messages
-t TIMEOUT | --timeout=TIMEOUT
Timeout in seconds, zero for no timeout
-- COMMAND ARGS Execute command with args after the test finishes
USAGE
exit 1
}
wait_for()
{
if [[ $WAITFORIT_TIMEOUT -gt 0 ]]; then
echoerr "$WAITFORIT_cmdname: waiting $WAITFORIT_TIMEOUT seconds for $WAITFORIT_HOST:$WAITFORIT_PORT"
else
echoerr "$WAITFORIT_cmdname: waiting for $WAITFORIT_HOST:$WAITFORIT_PORT without a timeout"
fi
WAITFORIT_start_ts=$(date +%s)
while :
do
if [[ $WAITFORIT_ISBUSY -eq 1 ]]; then
nc -z $WAITFORIT_HOST $WAITFORIT_PORT
WAITFORIT_result=$?
else
(echo > /dev/tcp/$WAITFORIT_HOST/$WAITFORIT_PORT) >/dev/null 2>&1
WAITFORIT_result=$?
fi
if [[ $WAITFORIT_result -eq 0 ]]; then
WAITFORIT_end_ts=$(date +%s)
echoerr "$WAITFORIT_cmdname: $WAITFORIT_HOST:$WAITFORIT_PORT is available after $((WAITFORIT_end_ts - WAITFORIT_start_ts)) seconds"
break
fi
sleep 1
done
return $WAITFORIT_result
}
wait_for_wrapper()
{
# In order to support SIGINT during timeout: http://unix.stackexchange.com/a/57692
if [[ $WAITFORIT_QUIET -eq 1 ]]; then
timeout $WAITFORIT_BUSYTIMEFLAG $WAITFORIT_TIMEOUT $0 --quiet --child --host=$WAITFORIT_HOST --port=$WAITFORIT_PORT --timeout=$WAITFORIT_TIMEOUT &
else
timeout $WAITFORIT_BUSYTIMEFLAG $WAITFORIT_TIMEOUT $0 --child --host=$WAITFORIT_HOST --port=$WAITFORIT_PORT --timeout=$WAITFORIT_TIMEOUT &
fi
WAITFORIT_PID=$!
trap "kill -INT -$WAITFORIT_PID" INT
wait $WAITFORIT_PID
WAITFORIT_RESULT=$?
if [[ $WAITFORIT_RESULT -ne 0 ]]; then
echoerr "$WAITFORIT_cmdname: timeout occurred after waiting $WAITFORIT_TIMEOUT seconds for $WAITFORIT_HOST:$WAITFORIT_PORT"
fi
return $WAITFORIT_RESULT
}
# process arguments
while [[ $# -gt 0 ]]
do
case "$1" in
*:* )
WAITFORIT_hostport=(${1//:/ })
WAITFORIT_HOST=${WAITFORIT_hostport[0]}
WAITFORIT_PORT=${WAITFORIT_hostport[1]}
shift 1
;;
--child)
WAITFORIT_CHILD=1
shift 1
;;
-q | --quiet)
WAITFORIT_QUIET=1
shift 1
;;
-s | --strict)
WAITFORIT_STRICT=1
shift 1
;;
-h)
WAITFORIT_HOST="$2"
if [[ $WAITFORIT_HOST == "" ]]; then break; fi
shift 2
;;
--host=*)
WAITFORIT_HOST="${1#*=}"
shift 1
;;
-p)
WAITFORIT_PORT="$2"
if [[ $WAITFORIT_PORT == "" ]]; then break; fi
shift 2
;;
--port=*)
WAITFORIT_PORT="${1#*=}"
shift 1
;;
-t)
WAITFORIT_TIMEOUT="$2"
if [[ $WAITFORIT_TIMEOUT == "" ]]; then break; fi
shift 2
;;
--timeout=*)
WAITFORIT_TIMEOUT="${1#*=}"
shift 1
;;
--)
shift
WAITFORIT_CLI=("$@")
break
;;
--help)
usage
;;
*)
echoerr "Unknown argument: $1"
usage
;;
esac
done
if [[ "$WAITFORIT_HOST" == "" || "$WAITFORIT_PORT" == "" ]]; then
echoerr "Error: you need to provide a host and port to test."
usage
fi
WAITFORIT_TIMEOUT=${WAITFORIT_TIMEOUT:-15}
WAITFORIT_STRICT=${WAITFORIT_STRICT:-0}
WAITFORIT_CHILD=${WAITFORIT_CHILD:-0}
WAITFORIT_QUIET=${WAITFORIT_QUIET:-0}
# check to see if timeout is from busybox?
WAITFORIT_TIMEOUT_PATH=$(type -p timeout)
WAITFORIT_TIMEOUT_PATH=$(realpath $WAITFORIT_TIMEOUT_PATH 2>/dev/null || readlink -f $WAITFORIT_TIMEOUT_PATH)
if [[ $WAITFORIT_TIMEOUT_PATH =~ "busybox" ]]; then
WAITFORIT_ISBUSY=1
WAITFORIT_BUSYTIMEFLAG="-t"
else
WAITFORIT_ISBUSY=0
WAITFORIT_BUSYTIMEFLAG=""
fi
if [[ $WAITFORIT_CHILD -gt 0 ]]; then
wait_for
WAITFORIT_RESULT=$?
exit $WAITFORIT_RESULT
else
if [[ $WAITFORIT_TIMEOUT -gt 0 ]]; then
wait_for_wrapper
WAITFORIT_RESULT=$?
else
wait_for
WAITFORIT_RESULT=$?
fi
fi
if [[ $WAITFORIT_CLI != "" ]]; then
if [[ $WAITFORIT_RESULT -ne 0 && $WAITFORIT_STRICT -eq 1 ]]; then
echoerr "$WAITFORIT_cmdname: strict mode, refusing to execute subprocess"
exit $WAITFORIT_RESULT
fi
exec "${WAITFORIT_CLI[@]}"
else
exit $WAITFORIT_RESULT
fi
Błąd
com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure
wait-for-it.sh jest w głównym katalogu projektu, tak samo jak Dockerfile i docker-compose.yml.