Update container functions to use Podman (#411)

* Update container functions to use Podman

* Add containerEngine property to devcmetadata.xml and refactor container command logic

* Use CONTAINER_TIMEOUT instead of DOCKER_TIMEOUT

.gitignore

@@ -2,6 +2,7 @@
 .project
 .settings
 target
+.DS_Store
 
 # Compiled class file
 *.class

src/main/java/io/openliberty/tools/common/plugins/util/AbstractContainerSupportUtil.java

@@ -1,3 +1,19 @@
+/**
+ * (C) Copyright IBM Corporation 2020, 2023.
+ *
+ * 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.openliberty.tools.common.plugins.util;
 
 import java.io.BufferedReader;
@@ -7,6 +23,14 @@
 
 public abstract class AbstractContainerSupportUtil {
 
+    private static final String CONTAINER_DOCKER_PREFIX = "docker ";
+    private static final String CONTAINER_PODMAN_PREFIX = "podman ";
+
+    protected static final int CONTAINER_TIMEOUT = 20; // seconds
+
+    private   boolean checkedContainerType = false;
+    protected boolean isDocker = true;
+
     /**
      * Log debug
      * @param msg
@@ -21,21 +45,77 @@ public abstract class AbstractContainerSupportUtil {
      */
     public abstract void error(String msg, Throwable e);
 
+    /**
+     * Log info
+     * @param msg
+     */
+    public abstract void info(String msg);
+
+    protected String getContainerCommandPrefix() throws PluginExecutionException {
+        if (!checkedContainerType) {
+            checkDockerVersion();
+        }
+
+        return isDocker ? CONTAINER_DOCKER_PREFIX : CONTAINER_PODMAN_PREFIX;
+    }
+
+    /**
+     * Retrieve the current docker version and compare to a known value.
+     * The Maven class ComparableVersion allows for numbers, letters and certain words.
+     * Throw an exception if there is a problem with the version.
+     */
+    private static final String MIN_DOCKER_VERSION = "18.03.0"; // Must use Docker 18.03.0 or higher
+    protected void checkDockerVersion() throws PluginExecutionException {
+        String versionCmd = "docker version --format {{.Client.Version}}";
+        String dockerVersion = execContainerCmd(versionCmd, CONTAINER_TIMEOUT);
+        if (dockerVersion == null) {
+            checkPodmanVersion(); // Check Podman version if no Docker 
+            return;
+        }
+        debug("Detected Docker version: " + dockerVersion);
+
+        if (VersionUtility.compareArtifactVersion(dockerVersion, MIN_DOCKER_VERSION, false) < 0) {
+            checkPodmanVersion(); // Check that bad Docker version isn't just a Podman version
+            if (!isDocker) {
+                return;
+            }
+            throw new PluginExecutionException("The detected Docker client version number is not supported:" + dockerVersion.trim() + ". Docker version must be " + MIN_DOCKER_VERSION + " or higher.");
+        }
+        isDocker = true;
+        checkedContainerType = true;
+    }
+
+    private static final String MIN_PODMAN_VERSION = "4.4.4"; // Must use Docker 4.4.4 or higher
+    private void checkPodmanVersion() throws PluginExecutionException  {
+        String versionCmd = "podman version --format {{.Client.Version}}";
+        String podmanVersion = execContainerCmd(versionCmd, CONTAINER_TIMEOUT);
+        if (podmanVersion == null) {
+            return; // Can't tell if the version is valid.
+        }
+        debug("Detected Podman version: " + podmanVersion);
+
+        if (VersionUtility.compareArtifactVersion(podmanVersion, MIN_PODMAN_VERSION, false) < 0) {
+            throw new PluginExecutionException("The detected Podman client version number is not supported:" + podmanVersion.trim() + ". Podman version must be " + MIN_PODMAN_VERSION + " or higher.");
+        }
+        isDocker = false;
+        checkedContainerType = true;
+    }
+
     /**
      * @param timeout unit is seconds
      * @return the stdout of the command or null for no output on stdout
      */
-    protected String execDockerCmd(String command, int timeout, boolean throwExceptionOnError) {
+    protected String execContainerCmd(String command, int timeout, boolean throwExceptionOnError) {
         String result = null;
         try {
-            debug("execDocker, timeout=" + timeout + ", cmd=" + command);
+            debug("execContainer, timeout=" + timeout + ", cmd=" + command);
             Process p = Runtime.getRuntime().exec(command);
 
             p.waitFor(timeout, TimeUnit.SECONDS);
 
             // After waiting for the process, handle the error case and normal termination.
             if (p.exitValue() != 0) {
-                debug("Error running docker command, return value="+p.exitValue());
+                debug("Error running container command, return value="+p.exitValue());
                 // read messages from standard err
                 char[] d = new char[1023];
                 new InputStreamReader(p.getErrorStream()).read(d);
@@ -48,22 +128,40 @@ protected String execDockerCmd(String command, int timeout, boolean throwExcepti
             }
             result = readStdOut(p);
         } catch (IllegalThreadStateException  e) {
-            // the timeout was too short and the docker command has not yet completed. There is no exit value.
+            // the timeout was too short and the container command has not yet completed. There is no exit value.
             debug("IllegalThreadStateException, message="+e.getMessage());
-            error("The docker command did not complete within the timeout period: " + timeout + " seconds.", e);
-            throw new RuntimeException("The docker command did not complete within the timeout period: " + timeout + " seconds. ");
+            error("The container command did not complete within the timeout period: " + timeout + " seconds.", e);
+            throw new RuntimeException("The container command did not complete within the timeout period: " + timeout + " seconds. ");
         } catch (InterruptedException e) {
             // If a runtime exception occurred in the server task, log and rethrow
-            error("An interruption error occurred while running a docker command: " + e.getMessage(), e);
+            error("An interruption error occurred while running a container command: " + e.getMessage(), e);
             throw new RuntimeException(e.getMessage());
         } catch (IOException e) {
-            // If a runtime exception occurred in the server task, log and rethrow
-            error("An error occurred while running a docker command: " + e.getMessage(), e);
-            throw new RuntimeException(e.getMessage());
+            // Logging IOExceptions in info stream. This is thrown if Docker or Podman are not installed on the system.
+            info("An error occurred while running a container command: " + e.getMessage());
+            info("This message will occur when Docker or Podman are not installed.");
         }
         return result;
     }
 
+    protected String execContainerCmd(String command, int timeout) {
+        return execContainerCmd(command, timeout, true);
+    }
+
+    protected String execContainerCmdWithPrefix(String command, int timeout) {
+        return execContainerCmdWithPrefix(command, timeout, true);
+    }
+
+    protected String execContainerCmdWithPrefix(String command, int timeout, boolean throwExceptionOnError) {
+        try {
+            String containerCommand = getContainerCommandPrefix() + " " + command;
+            return execContainerCmd(containerCommand, timeout, throwExceptionOnError);
+        } catch (PluginExecutionException pe) {
+            error("Error while determining container command prefix.", pe);
+            return pe.getMessage();
+        }
+    }
+
     protected String readStdOut(Process p) throws IOException, InterruptedException {
         String result = null;
         // Read all the output on stdout and return it to the caller