hadoop-xml-conf.sh

#!/bin/bash
#
# Utility functions for processing Hadoop 2 XML configuration files.
# 
# Depends on Python built-in XML processing and libxml2 for formatting
#


installed=false
if [ -f /etc/profile.d/hadoop.sh ]; then
    source /etc/profile.d/hadoop.sh
    source $HADOOP_HOME/etc/hadoop/hadoop-env.sh
    installed=true
fi


create_config()
{
	local filename=
	
        case $1 in
            '')    echo $"$0: Usage: create_config --file"
                   return 1;;
            --file)
	           filename=$2
	           ;;
        esac
echo " create_config $filename"
	python - <<END
from xml.etree import ElementTree
from xml.etree.ElementTree import Element

conf = Element('configuration')

conf_file = open("$filename",'w')
conf_file.write(ElementTree.tostring(conf))
conf_file.close()
END

	write_file $filename
}

put_config()
{
	local filename= property= value=
	
        while [ "$1" != "" ]; do
        case $1 in
            '')    echo $"$0: Usage: put_config --file --property --value"
                   return 1;;
            --file)
                   filename=$2
                   shift 2
                   ;;
            --property)
                   property=$2
                   shift 2
                   ;;
            --value)
                   value=$2
                   shift 2
                   ;;
        esac
        done
echo " put_config $filename"

	python - <<END
from xml.etree import ElementTree
from xml.etree.ElementTree import Element
from xml.etree.ElementTree import SubElement

def putconfig(root, name, value):
	for existing_prop in root.getchildren():
		if existing_prop.find('name').text == name:
			root.remove(existing_prop)
			break
	
	property = SubElement(root, 'property')
	name_elem = SubElement(property, 'name')
	name_elem.text = name
	value_elem = SubElement(property, 'value')
	value_elem.text = value

path = ''
if "$installed" == 'true':
	path = "$HADOOP_CONF_DIR" + '/'

conf = ElementTree.parse(path + "$filename").getroot()
putconfig(root = conf, name = "$property", value = "$value")

conf_file = open("$filename",'w')
conf_file.write(ElementTree.tostring(conf))
conf_file.close()
END

	write_file $filename
}

del_config()
{
	local filename= property=

	while [ "$1" != "" ]; do	
        case $1 in
            '')    echo $"$0: Usage: del_config --file --property"
                   return 1;;
            --file)
                   filename=$2
                   shift 2
                   ;;
            --property)
                   property=$2
		   shift 2
                   ;;
        esac
	done

	python - <<END
from xml.etree import ElementTree
from xml.etree.ElementTree import Element
from xml.etree.ElementTree import SubElement

def delconfig(root, name):
	for existing_prop in root.getchildren():
		if existing_prop.find('name').text == name:
			root.remove(existing_prop)
			break

path = ''
if "$installed" == 'true':
        path = "$HADOOP_CONF_DIR" + '/'

conf = ElementTree.parse(path + "$filename").getroot()
delconfig(root = conf, name = "$property")

conf_file = open("$filename",'w')
conf_file.write(ElementTree.tostring(conf))
conf_file.close()
END
	write_file $filename
}

write_file()
{
	local file=$1

	xmllint --format "$file" > "$file".pp && mv "$file".pp "$file"
}