001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.lang3;
019
020import java.io.IOException;
021import java.nio.file.Files;
022import java.nio.file.Paths;
023import java.util.stream.Stream;
024
025/**
026 * Helps query the runtime environment.
027 *
028 * @since 3.15.0
029 */
030public class RuntimeEnvironment {
031
032    /**
033     * Tests whether the file at the given path string contains a specific line.
034     *
035     * @param path The path to a file.
036     * @param line The line to find.
037     * @return whether the file at the given path string contains a specific line.
038     */
039    private static Boolean containsLine(final String path, final String line) {
040        try (Stream<String> stream = Files.lines(Paths.get(path))) {
041            return stream.anyMatch(test -> test.contains(line));
042        } catch (final IOException e) {
043            return false;
044        }
045    }
046
047    /**
048     * Tests whether we are running in a container like Docker or Podman.
049     *
050     * @return whether we are running in a container like Docker or Podman.
051     */
052    public static Boolean inContainer() {
053        return inDocker() || inPodman();
054    }
055
056    /**
057     * Tests whether we are running in a Docker container.
058     * <p>
059     * Package-private for testing.
060     * </p>
061     *
062     * @return whether we are running in a Docker container.
063     */
064    // Could be public at a later time.
065    static Boolean inDocker() {
066        return containsLine("/proc/1/cgroup", "/docker");
067    }
068
069    /**
070     * Tests whether we are running in a Podman container.
071     * <p>
072     * Package-private for testing.
073     * </p>
074     *
075     * @return whether we are running in a Podman container.
076     */
077    // Could be public at a later time.
078    static Boolean inPodman() {
079        return containsLine("/proc/1/environ", "container=podman");
080    }
081
082    /**
083     * Tests whether we are running in a Windows Subsystem for Linux (WSL).
084     * <p>
085     * Package-private for testing.
086     * </p>
087     *
088     * @return whether we are running in a Windows Subsystem for Linux (WSL).
089     */
090    // Could be public at a later time.
091    static Boolean inWsl() {
092        return containsLine("/proc/1/environ", "container=wslcontainer_host_id");
093    }
094
095    /**
096     * Constructs a new instance.
097     *
098     * @deprecated Will be removed in 4.0.0.
099     */
100    @Deprecated
101    public RuntimeEnvironment() {
102        // empty
103    }
104}