HADOOP-13356. Add a function to handle command_subcommand_OPTS (aw)

Signed-off-by: Allen Wittenauer <aw@apache.org>

hadoop-common-project/hadoop-common/src/main/bin/hadoop-functions.sh

@@ -1974,6 +1974,68 @@ function hadoop_verify_user
   fi
 }
 
+## @description  Add custom (program)_(command)_OPTS to HADOOP_OPTS.
+## @description  Also handles the deprecated cases from pre-3.x.
+## @audience     public
+## @stability    stable
+## @replaceable  yes
+## @param        program
+## @param        subcommand
+## @return       will exit on failure conditions
+function hadoop_subcommand_opts
+{
+  declare program=$1
+  declare command=$2
+  declare var
+  declare uvar
+  declare uprogram
+  declare ucommand
+
+  if [[ -z "${program}" || -z "${command}" ]]; then
+    return 1
+  fi
+
+  # bash 4 and up have built-in ways to upper and lower
+  # case the contents of vars.  This is faster than
+  # calling tr.
+
+  if [[ -z "${BASH_VERSINFO[0]}" ]] \
+     || [[ "${BASH_VERSINFO[0]}" -lt 4 ]]; then
+    uprogram=$(echo "${program}" | tr '[:lower:]' '[:upper:]')
+    ucommand=$(echo "${command}" | tr '[:lower:]' '[:upper:]')
+  else
+    uprogram=${program^^}
+    ucommand=${command^^}
+  fi
+
+  # HDFS_namenode_OPTS
+  # HADOOP_distcp_OPTS
+  # MAPRED_distcp_OPTS
+  # YARN_sharedcachemanger_OPTS
+  # ...
+  var="${uprogram}_${command}_OPTS"
+
+  # Let's handle all of the deprecation cases early
+  # HADOOP_NAMENODE_OPTS -> HDFS_namenode_OPTS
+  # YARN_RESOURCEMANAGER_OPTS -> YARN_resourcemanager_OPTS
+
+  uvar="${uprogram}_${ucommand}_OPTS"
+  if [[ -n ${!uvar} ]]; then
+    hadoop_deprecate_envvar "${uvar}" "${var}"
+  fi
+
+  uvar="HADOOP_${ucommand}_OPTS"
+  if [[ -n ${!uvar} ]]; then
+    hadoop_deprecate_envvar "${uvar}" "${var}"
+  fi
+
+  if [[ -n ${!var} ]]; then
+    hadoop_debug "Appending ${!var} onto HADOOP_OPTS"
+    HADOOP_OPTS="${HADOOP_OPTS} ${!var}"
+    return 0
+  fi
+}
+
 ## @description  Perform the 'hadoop classpath', etc subcommand with the given
 ## @description  parameters
 ## @audience     private

hadoop-common-project/hadoop-common/src/test/scripts/hadoop_subcommand_opts.bats

@@ -0,0 +1,76 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You 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.
+
+load hadoop-functions_test_helper
+
+@test "hadoop_subcommand_opts (missing param)" {
+  HADOOP_OPTS="x"
+  run hadoop_subcommand_opts testvar
+  [ "${status}" = "1" ]
+}
+
+@test "hadoop_subcommand_opts (simple not exist)" {
+  HADOOP_OPTS="x"
+  hadoop_subcommand_opts hadoop subcommand
+  [ "${HADOOP_OPTS}" = "x" ]
+}
+
+@test "hadoop_subcommand_opts (hadoop simple exist)" {
+  HADOOP_OPTS="x"
+  HADOOP_test_OPTS="y"
+  hadoop_subcommand_opts hadoop test
+  echo "${HADOOP_OPTS}"
+  [ "${HADOOP_OPTS}" = "x y" ]
+}
+
+@test "hadoop_subcommand_opts (hadoop complex exist)" {
+  HADOOP_OPTS="x"
+  HADOOP_test_OPTS="y z"
+  hadoop_subcommand_opts hadoop test
+  echo "${HADOOP_OPTS}"
+  [ "${HADOOP_OPTS}" = "x y z" ]
+}
+
+@test "hadoop_subcommand_opts (hdfs simple exist)" {
+  HADOOP_OPTS="x"
+  HDFS_test_OPTS="y"
+  hadoop_subcommand_opts hdfs test
+  echo "${HADOOP_OPTS}"
+  [ "${HADOOP_OPTS}" = "x y" ]
+}
+
+@test "hadoop_subcommand_opts (yarn simple exist)" {
+  HADOOP_OPTS="x"
+  YARN_test_OPTS="y"
+  hadoop_subcommand_opts yarn test
+  echo "${HADOOP_OPTS}"
+  [ "${HADOOP_OPTS}" = "x y" ]
+}
+
+@test "hadoop_subcommand_opts (deprecation case #1)" {
+  HADOOP_OPTS="x"
+  HADOOP_NAMENODE_OPTS="y"
+  hadoop_subcommand_opts hdfs namenode
+  echo "${HADOOP_OPTS}"
+  [ "${HADOOP_OPTS}" = "x y" ]
+}
+
+@test "hadoop_subcommand_opts (deprecation case #2)" {
+  HADOOP_OPTS="x"
+  YARN_RESOURCEMANAGER_OPTS="y"
+  hadoop_subcommand_opts yarn resourcemanager
+  echo "${HADOOP_OPTS}"
+  [ "${HADOOP_OPTS}" = "x y" ]
+}