Solr Start - Stop script

Solr

Solr is highly reliable, scalable and fault tolerant, providing distributed indexing, replication and load-balanced querying, automated failover and recovery, centralized configuration and more. Solr powers the search and navigation features of many of the world's largest internet sites.

Introduction

You can download the solr from here.  Setting up solr is easy as they have perfect document to do that.  Starting the solr is also easy. Go to the path, start the solr by the command what they have provided for the version you have downloaded.  By pressing Ctrl + c or by killing the port you can easily start and restart the solr.

Consider the production environment. You don't have to manually follow this process each and every time. To simplify this tedious process, follow the below steps.

Implementation

	#!/bin/sh
	# This script will launch Solr in a mode that will automatically respawn if it
	# crashes. Output will be sent to /var/log/solr/solr.log. A PID file will be
	# created in the standard location.
	start () {
	daemon --running --verbose --name=solr
	RETVAL1=$?
	if [ $RETVAL1 = 0 ]
	then
	echo "Solr is already running"
	else
	echo -n "Starting solr..."
	# Start daemon
	daemon --chdir='/home/chezhian/Chezhian_files/solr/solr-4.7.0/example' --command "java -jar start.jar" --respawn --output=/var/log/solr/solr.log --name=solr --verbose
	RETVAL=$?
	if [ $RETVAL = 0 ]
	then
	echo "done."
	else
	echo "failed. See error code for more information."
	fi
	return $RETVAL
	fi
	}
	stop () {
	# Stop daemon
	echo -n "Stopping solr..."
	daemon --stop --name=solr --verbose
	RETVAL=$?
	if [ $RETVAL = 0 ]
	then
	echo "Done."
	else
	echo "Failed. See error code for more information."
	fi
	return $RETVAL
	}
	restart () {
	daemon --restart --name=solr --verbose
	}
	status () {
	# Report on the status of the daemon
	daemon --running --verbose --name=solr
	return $?
	}
	case "$1" in
	start)
	start
	;;
	status)
	status
	;;
	stop)
	stop
	;;
	restart)
	restart
	;;
	*)
	echo $"Usage: solr {start|status|stop|restart}"
	exit 3
	;;
	esac
	exit $RETVAL

view raw blog-4-1.sh hosted with ❤ by GitHub

• copy the above code and paste in /etc/init.d/solr file
• mention your solr path, and start command in the start daemon place
• following needs to be done in the server ( just copy paste in your terminal )

sudo update-rc.d solr defaults
sudo apt-get install chkconfig
update-rc.d solr defaults
sudo chmod og+x /etc/init.d/solr
sudo apt-get install daemon

Then you can start and stop the solr by the following command

/etc/init.d/solr start
/etc/init.d/solr stop

Thats it, now you can start and stop solr by the above command.

Dry concept for implementing JS plugins - tokeninput

Rails is always suggesting us to use DRY concept in our codes, and there are plenty of ways to achieve that.

Here I am gonna explain how we can achieve the DRY concept in adding JavaScript functionality to our Rails applications.

For explanation I have taken jQuery Tokeninput as an example.

Usually we add a plugin to our app in the following way.

	$(document).ready(function() {
	$("#token-input").tokenInput("http://my-own-app.com/tokeninput/json", {
	preventDuplicates: false,
	tokenLimit: 10,
	hintText: 'Type to Fetch Data',
	noResultsText: 'No Data Found',
	searchingText: 'Fetching Data',
	onAdd: function(item) { alert('added successfully') },
	onDelete: function(item) { alert('deleted successfully') },
	prePopulate: [{id: 7, name: "Ruby"}, {id: 11, name: "Python"}],
	theme: 'mac'
	});
	});

view raw blog-3-1.js hosted with ❤ by GitHub

Consider, the same html page is having auto complete for 3 elements.  Then you have to repeat the same code 3 times.  If the auto complete is added for many elements in the app, then you have to repeat the same code wherever it is necessary.

The same can be rewritten like below

	function call_auto_complete(call_class) {
	$.each($("." + call_class), function(index, value) {
	$("#" + $(this).attr("id")).tokenInput($(this).attr("data-url"), {
	preventDuplicates: "false" === $(this).attr("data-duplicate") ? false : true,
	tokenLimit: null == $(this).attr("data-selection-limit") ? null : $(this).attr("data-selection-limit"),
	hintText: null == $(this).attr("data-hint-text") ? "Type to Fetch Data" : $(this).attr("data-hint-text"),
	noResultsText: null == $(this).attr("data-no-result") ? "No Data Found" : $(this).attr("data-no-result"),
	searchingText: null == $(this).attr("data-searching-text") ? "Fetching Data" : $(this).attr("data-searching-text"),
	onAdd: function(item) {
	null == $(this).attr("data-on-add-call-function") ? {} : eval($(this).attr("data-on-add-call-function") + "(item.id, $(this).attr('data-success-update'))") },
	onDelete: function() {
	null == $(this).attr("data-on-delete-call-function") ? [] : eval($(this).attr("data-on-delete-call-function") + "($(this).attr('data-success-update'))")},
	prePopulate: null == $(this).attr("data-selected") ? [] : eval($(this).attr("data-selected")),
	theme: null == $(this).attr("data-theme") ? "mac" : $(this).attr("data-theme")
	})
	})
	}
	$(document).ready(
	function() {
	call_auto_complete("auto_complete");
	}
	)

view raw blog-3-2.js hosted with ❤ by GitHub

In html.erb you can call the function like below

<% selected_countries = @user.countries.map { |c| { id: c.id, name: c.name } } %>

<%= text_field_tag("users[country_id]", {}, { :class => "auto_complete", "data-url" => "/users/get_countries", "data-duplicate" => "false", "data-selection-limit" => "10", "data-hint-text" => "Type to search  Country", "data-no-result" => "No Country found", "data-searching-text" => "Fetching Countries", "data-selected" => (selected_countries).to_json }) %>

By this way, wherever you need the autocomplete, just add the class 'auto_complete', or the class whatever you want.  Then that text field will be converted as auto complete dynamically based on the data attributes passed to the function.  So this will drastically reduce your code repetition on JavaScript side.

And you can easily call this same function on ajax success also, no need to load the JavaScript file one more time.

Above mentioned code example is for jquery tokeninput plugin, but the same behavior can be used in other plugin implementation too.