io.rxmicro.config.WaitFor Maven / Gradle / Ivy
/*
* Copyright (c) 2020. https://rxmicro.io
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.rxmicro.config;
import io.rxmicro.config.internal.waitfor.WaitForService;
import static io.rxmicro.config.internal.waitfor.WaitForServiceFactory.createWaitForService;
/**
* Allows suspending current thread until configured service is up.
*
*
* Example of usage:
*
* public static void main(final String[] args) {
* new WaitFor(args).waitFor();
* startRestServer(MicroService.class);
* }
*
*
*
* Command line arguments:
*
*
*
* - {@code java -p lib:. -m my.module/my_package.Launcher wait-for --type=tcp-socket --timeout=30 localhost:12017}
* - {@code java -p lib:. -m my.module/my_package.Launcher wait-for localhost:12017 }
*
*
*
* Using java system properties:
*
*
*
* - {@code SYS_PROP="-DWAIT_FOR=--type=tcp-socket --timeout=30 localhost:12017"}
* - {@code java -p lib:. "$SYS_PROP" -m my.module/my_package.Launcher }
*
* - {@code SYS_PROP="-DWAIT_FOR=localhost:12017" }
* - {@code java -p lib:. "$SYS_PROP" -m my.module/my_package.Launcher }
*
*
*
* Using environment variables:
*
*
*
* - {@code export WAIT_FOR="--type=tcp-socket --timeout=30 localhost:12017"}
* - {@code java -p lib:. -m my.module/my_package.Launcher}
*
* - {@code export WAIT_FOR=localhost:12017}
* - {@code java -p lib:. -m my.module/my_package.Launcher}
*
*
* @author nedis
* @see java.net.Socket
* @since 0.3
*/
public final class WaitFor {
/**
* For configuration WaitForService using environment variables or Java system properties, use {@code `WAIT_FOR`} name.
*/
public static final String WAIT_FOR_ENV_VAR_OR_JAVA_SYS_PROP_NAME = "WAIT_FOR";
/**
* For configuration WaitForService using command line arguments, use {@code `wait-for`} name.
*/
public static final String WAIT_FOR_COMMAND_LINE_ARG = "wait-for";
/**
* Wait for type parameter.
*/
public static final String WAIT_FOR_TYPE_PARAM_NAME = "type";
/**
* Wait for delimiter character.
*/
public static final String WAIT_FOR_DELIMITER = "&";
/**
* Wait for param prefix.
*/
public static final String WAIT_FOR_PARAM_PREFIX = "--";
/**
* Default wait for type: {@code tcp-socket}.
*/
public static final String WAIT_FOR_TCP_SOCKET_TYPE_NAME = "tcp-socket";
/**
* Wait for timeout.
*
*
* Integer value means timeout in seconds, i.e. {@code `--timeout=5`} equals to {@code `--timeout=5 seconds`}
*
*
* Other units can be used as string using Duration format:
*
* - {@code `--timeout=PT15M`} equals to {@code `--timeout=15 minutes`}
* - {@code `--timeout=P2D`} equals to {@code `--timeout=2 days`}
*
*
*
* See for detail: {@link java.time.Duration#parse(CharSequence)}
*/
public static final String WAIT_FOR_TIMEOUT = "timeout";
/**
* Default timeout value.
*/
public static final String WAIT_FOR_TIMEOUT_DEFAULT_VALUE_IN_SECONDS = "10";
private final WaitForService waitForService;
/**
* Creates a WaitFor instance.
*
* @param commandLineArgs command line arguments
* @throws ConfigException if the provided arguments are not valid
*/
public WaitFor(final String commandLineArgs) {
if (commandLineArgs.indexOf(' ') != -1) {
waitForService = createWaitForService(commandLineArgs.split(" ")).orElse(null);
} else {
waitForService = createWaitForService(new String[]{commandLineArgs}).orElse(null);
}
}
/**
* Creates a WaitFor instance.
*
* @param commandLineArgs command line arguments
* @throws ConfigException if the provided arguments are not valid
*/
public WaitFor(final String... commandLineArgs) {
waitForService = createWaitForService(commandLineArgs).orElse(null);
}
/**
* Starts the suspending the current thread until configured service is up.
*
*
* If current environment does not enable {@link WaitFor} this method does nothing.
*
* @throws ServiceYetNotAvailableException if configured service is not up.
*/
public void start() {
if (waitForService != null) {
waitForService.start();
}
}
}