YARN-10312. Add support for yarn logs -logFile to retain backward compatibility.

Contributed by Jim Brennan.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/main/java/org/apache/hadoop/yarn/client/cli/LogsCLI.java

@@ -100,6 +100,7 @@ public class LogsCLI extends Configured implements Tool {
   private static final String APP_OWNER_OPTION = "appOwner";
   private static final String AM_CONTAINER_OPTION = "am";
   private static final String PER_CONTAINER_LOG_FILES_OPTION = "log_files";
+  private static final String PER_CONTAINER_LOG_FILES_OLD_OPTION = "logFiles";
   private static final String PER_CONTAINER_LOG_FILES_REGEX_OPTION
       = "log_files_pattern";
   private static final String LIST_NODES_OPTION = "list_nodes";
@@ -202,6 +203,12 @@ public class LogsCLI extends Configured implements Tool {
       }
       if (commandLine.hasOption(PER_CONTAINER_LOG_FILES_OPTION)) {
         logFiles = commandLine.getOptionValues(PER_CONTAINER_LOG_FILES_OPTION);
+      } else {
+        // For backward compatibility, we need to check for the old form of this
+        // command line option as well.  New form takes precedent.
+        if (commandLine.hasOption(PER_CONTAINER_LOG_FILES_OLD_OPTION)) {
+          logFiles = commandLine.getOptionValues(PER_CONTAINER_LOG_FILES_OLD_OPTION);
+        }
       }
       if (commandLine.hasOption(PER_CONTAINER_LOG_FILES_REGEX_OPTION)) {
         logFilesRegex = commandLine.getOptionValues(
@@ -937,6 +944,12 @@ public class LogsCLI extends Configured implements Tool {
     logFileOpt.setArgs(Option.UNLIMITED_VALUES);
     logFileOpt.setArgName("Log File Name");
     opts.addOption(logFileOpt);
+    Option oldLogFileOpt = new Option(PER_CONTAINER_LOG_FILES_OLD_OPTION, true,
+        "Deprecated name for log_files, please use log_files option instead");
+    oldLogFileOpt.setValueSeparator(',');
+    oldLogFileOpt.setArgs(Option.UNLIMITED_VALUES);
+    oldLogFileOpt.setArgName("Log File Name");
+    opts.addOption(oldLogFileOpt);
     Option logFileRegexOpt = new Option(PER_CONTAINER_LOG_FILES_REGEX_OPTION,
         true, "Specify comma-separated value "
         + "to get matched log files by using java regex. Use \".*\" to "

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/test/java/org/apache/hadoop/yarn/client/cli/TestLogsCLI.java

@@ -529,6 +529,48 @@ public class TestLogsCLI {
         createEmptyLog("empty")));
     sysOutStream.reset();
 
+    // Check backward compatibility for -logFiles
+    exitCode = cli.run(new String[] {"-applicationId", appId.toString(),
+        "-logFiles", "stdout"});
+    assertTrue("Failed with -logFiles", exitCode == 0);
+    assertFalse("Failed with -logFiles", sysOutStream.toString().contains(
+        logMessage(containerId1, "syslog")));
+    assertFalse("Failed with -logFiles", sysOutStream.toString().contains(
+        logMessage(containerId2, "syslog")));
+    assertFalse("Failed with -logFiles", sysOutStream.toString().contains(
+        logMessage(containerId3, "syslog")));
+    assertTrue("Failed with -logFiles", sysOutStream.toString().contains(
+        logMessage(containerId3, "stdout")));
+    assertFalse("Failed with -logFiles", sysOutStream.toString().contains(
+        logMessage(containerId3, "stdout1234")));
+    assertFalse("Failed with -logFiles", sysOutStream.toString().contains(
+        createEmptyLog("empty")));
+    sysOutStream.reset();
+
+    // Check -log_files supercedes -logFiles
+    exitCode = cli.run(new String[] {"-applicationId", appId.toString(),
+        "-log_files", "stdout", "-logFiles", "syslog"});
+    assertTrue("Failed with -logFiles and -log_files", exitCode == 0);
+    assertFalse("Failed with -logFiles and -log_files",
+        sysOutStream.toString().contains(
+        logMessage(containerId1, "syslog")));
+    assertFalse("Failed with -logFiles and -log_files",
+        sysOutStream.toString().contains(
+        logMessage(containerId2, "syslog")));
+    assertFalse("Failed with -logFiles and -log_files",
+        sysOutStream.toString().contains(
+        logMessage(containerId3, "syslog")));
+    assertTrue("Failed with -logFiles and -log_files",
+        sysOutStream.toString().contains(
+        logMessage(containerId3, "stdout")));
+    assertFalse("Failed with -logFiles and -log_files",
+        sysOutStream.toString().contains(
+        logMessage(containerId3, "stdout1234")));
+    assertFalse("Failed with -logFiles and -log_files",
+        sysOutStream.toString().contains(
+        createEmptyLog("empty")));
+    sysOutStream.reset();
+
     exitCode = cli.run(new String[] {"-applicationId", appId.toString(),
         "-log_files_pattern", "std*"});
     assertTrue(exitCode == 0);