mongoDB – under SUSE SLE11 – SP3

Getting started with mongoDB under Suse Linux. Installation:

zypper addrepo --no-gpgcheck http://repo.mongodb.org/zypper/suse/11/mongodb-org#
sudo zypper install mongodb-org
vi /etc/mongod.conf

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zypper addrepo --no-gpgcheck http://repo.mongodb.org/zypper/suse/11/mongodb-org#

sudo zypper install mongodb-org

vi /etc/mongod.conf

Note: Default port is 27017 Starting/Stopping mongoDB server:

sudo service mongod start
sudo service mongod stop

1 2	sudo service mongod start sudo service mongod stop

Verify server status:

tail -f /var/log/mongodb/mongod.log

1	tail -f /var/log/mongodb/mongod.log

Make it part of the autostart for different run levels:

sudo chkconfig mongod on

1	sudo chkconfig mongod on

Getting started with mongoDB

Hide/Show Desktop Icons on SUSE

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Sometimes it is desirable to have a clean desktop. The following steps will allow you to achieve that with minimal commands.

- open a terminal
- type gconf-editor
- navigate apps/nautilus/desktop
- Select/De-select the items you want to display on the desktop.
- Exit from there and you are done!

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- open a terminal

- type gconf-editor

- navigate apps/nautilus/desktop

- Select/De-select the items you want to display on the desktop.

- Exit from there and you are done!

Mojolicious

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Quick Install:

curl -L https://cpanmin.us | perl - -M https://cpan.metacpan.org -n Mojolicious

1	curl -L https://cpanmin.us \| perl - -M https://cpan.metacpan.org -n Mojolicious

Parent Link: http://mojolicio.us/ Gererating a Lite App called hello_world:

mojo generate lite_app hello_world

1	mojo generate lite_app hello_world

Place holders:

/:foo - Generic place holder
/(.foo) - Relaxed place holder which accepts dots
/*foo - Wildcard place holder which accepts dots and forward slashes

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/:foo - Generic place holder

/(.foo) - Relaxed place holder which accepts dots

/*foo - Wildcard place holder which accepts dots and forward slashes

Using the above 3 you could drive with 2 more place holders.

optional place holder - specifying a default value makes a place holder optional.
restrictive place holder - Specifying a set of values makes the place holder restricted.

1 2	optional place holder - specifying a default value makes a place holder optional. restrictive place holder - Specifying a set of values makes the place holder restricted.

Using CPAN to install Mojolicious Plugins:

curl -L cpanmin.us | perl - App::cpanmius

1	curl -L cpanmin.us \| perl - App::cpanmius

Once the cpanminus tools are installed, you could use cpanm to download and install plugins.

cpanm Mojolicious::Plugin::ParmsAuth

1	cpanm Mojolicious::Plugin::ParmsAuth

Storing Values:

stash - works only with current request
flash - works only with the next (future) request
session - works with all request until deleted or expired

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stash - works only with current request

flash - works only with the next (future) request

session - works with all request until deleted or expired

Debugging Mojo code:

MOJO_USERAGENT_DEBUG=1 perl mojo_script_name.pl

1	MOJO_USERAGENT_DEBUG=1 perl mojo_script_name.pl

Finding …

my .vimrc

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Here is my .vimrc file on a SUSE SLE11-SP3 box

set nu
set laststatus=10
set autoindent
set tabstop=2
set shiftwidth=2
set smartindent
set expandtab
syntax on
   
set textwidth=79
set formatoptions=qrn1
"if version >= 703
if exists('+colorcolumn')
  set colorcolumn=80
endif
   
set history=500
set nobackup
set noswapfile
"set list
"set listchars=tab:.\ ,trail:.,extends:#,nbsp:.
set listchars=tab:▸\ ,eol:¬,extends:#,nbsp:.,trail:.
   
if has("gui_running")
  set guifont=DEC\ Terminal
  "colorscheme darkblue
  colorscheme evening
  set guioptions-=r
  set go-=L
  set go-=T
else
  colorscheme darkblue
endif
   
"line tracking
set numberwidth=5
set cursorline
set cursorcolumn
   
" turn off cursor blinking
set guicursor+=a:blinkon0

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set nu

set laststatus=10

set autoindent

set tabstop=2

set shiftwidth=2

set smartindent

set expandtab

syntax on

set textwidth=79

set formatoptions=qrn1

"if version >= 703

if exists('+colorcolumn')

set colorcolumn=80

endif

set history=500

set nobackup

set noswapfile

"set list

"set listchars=tab:.\ ,trail:.,extends:#,nbsp:.

set listchars=tab:▸\ ,eol:¬,extends:#,nbsp:.,trail:.

if has("gui_running")

set guifont=DEC\ Terminal

"colorscheme darkblue

colorscheme evening

set guioptions-=r

set go-=L

set go-=T

else

colorscheme darkblue

endif

"line tracking

set numberwidth=5

set cursorline

set cursorcolumn

" turn off cursor blinking

set guicursor+=a:blinkon0

LAMP – install on Ubuntu

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Easiest way to install LAMP stack on Ubuntu servers

sudo apt-get update
sudo apt-get install lamp-server^

1 2	sudo apt-get update sudo apt-get install lamp-server^

Yes the ^ is needed.

Build & Install node.js from source code

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Following instructions are tested on Ubuntu 10.04 & node v0.12.2 download node package from http://nodejs.org/dist/latest/ tar -xvzf node-v0.12.2.tar.gz cd node-v0.12.2 Run the following commands

./configure
make
sudo make install

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./configure

make

sudo make install

To test the install

~$ node 
> 
(^C again to quit)
>

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~$ node

>

(^C again to quit)

>

Hello World Test! vi hello.node.js

console.log("Hello, World!")

1	console.log("Hello, World!")

To Run,

node hello.node.js

1	node hello.node.js

Let’s do something more than Hello World.

vi http.test.js

1	vi http.test.js

var http = require("http");

http.createServer(function (request, response) {
   // Send HTTP Status: 200 : OK
   // Content Type: text/plain
   response.writeHead(200, {'Content-Type': 'text/plain'});
   
   // Send the response body as "Hello World"
   response.end('Hello World\n');
}).listen(8888);

// Console will print the message
console.log('Server running at http://127.0.0.1:8888/');

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var http = require("http");

http.createServer(function (request, response) {

// Send HTTP Status: 200 : OK

// Content Type: text/plain

response.writeHead(200, {'Content-Type': 'text/plain'});

// Send the response body as "Hello World"

response.end('Hello World\n');

}).listen(8888);

// Console will print the message

console.log('Server running at http://127.0.0.1:8888/');

To test the above code

On a Console: node http.test.js
On a Web browser: http://127.0.0.1:8888

1 2	On a Console: node http.test.js On a Web browser: http://127.0.0.1:8888

jQuery Fundamentals

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The jQuery library provides the jQuery function,

var listItems = jQuery( 'li' );

1	var listItems = jQuery( 'li' );

Is same as…

var listItems = $( 'li' );

1	var listItems = $( 'li' );

Which select all ‘li’ elements. The following ensures the page is ready for jQuery operations.

$(document).ready()

1	$(document).ready()

Is same as…

$()

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$()

Example:

// $( document ).ready(function() {
$(function() {
  console.log( 'ready!' );
});

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// $( document ).ready(function() {

$(function() {

console.log( 'ready!' );

});

Get some elements from a page

$( '#header' ); // select the element with an ID of 'header'
$( 'li' );      // select all list items on the page
$( 'ul li' );   // select list items that are in unordered lists
$( '.person' ); // select all elements with a class of 'person'

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$( '#header' ); // select the element with an ID of 'header'

$( 'li' ); // select all list items on the page

$( 'ul li' ); // select list items that are in unordered lists

$( '.person' ); // select all elements with a class of 'person'

Filtering selections with jQuery:

var listItems = $( 'li' );

// filter the selection to only items with a class of 'special'
var special = listItems.filter( '.special' );

// filter the selection to only items without a class of 'special'
var notSpecial = listItems.not( '.special' );

// filter the selection to only items that contain a span
var hasSpans = listItems.has( 'span' );

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var listItems = $( 'li' );

// filter the selection to only items with a class of 'special'

var special = listItems.filter( '.special' );

// filter the selection to only items without a class of 'special'

var notSpecial = listItems.not( '.special' );

// filter the selection to only items that contain a span

var hasSpans = listItems.has( 'span' );

Events

$( '#my-unordered-list' ).on( 'click', 'li', function( event ) {
  console.log( this ); // logs the list item that was clicked
});

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$( '#my-unordered-list' ).on( 'click', 'li', function( event ) {

console.log( this ); // logs the list item that was clicked

});

Effects

.show() Show the selected elements.
.hide() Hide the selected elements.
.fadeIn() Animate the opacity of the selected elements to 100%.
.fadeOut() Animate the opacity of the selected elements to 0%.
.slideDown() Display the selected elements with a vertical sliding motion.
.slideUp() Hide the selected elements with a vertical sliding motion.
.slideToggle() Show or hide the selected elements with a vertical sliding motion.

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.show() Show the selected elements.

.hide() Hide the selected elements.

.fadeIn() Animate the opacity of the selected elements to 100%.

.fadeOut() Animate the opacity of the selected elements to 0%.

.slideDown() Display the selected elements with a vertical sliding motion.

.slideUp() Hide the selected elements with a vertical sliding motion.

.slideToggle() Show or hide the selected elements with a vertical sliding motion.

Custom effects with .animate()

$( '.funtimes' ).animate({
    left: '+=50', // increase by 50
    opacity: 0.25,
    fontSize: '12px'
  },
  300,
  function() {
    // executes when the animation is done
  }
);

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$( '.funtimes' ).animate({

left: '+=50', // increase by 50

opacity: 0.25,

fontSize: '12px'

},

300,

function() {

// executes when the animation is done

}

);

Managing animate

.stop() will stop currently running animations on the selected elements.
.delay() will pause before the execution of the next animation method.

1 2	.stop() will stop currently running animations on the selected elements. .delay() will pause before the execution of the next animation method.

dummy sendmail

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Lets say you are developing an app that sends mail, but you don’t want to actually send any mails out. The answer for your quest is “dummy sendmail”

#!/bin/bash
# replace the /usr/bin/sendail with this shell script.
# Everytime someone sends a mail, the content of the mail will be written to a file under /tmp/mail.20150203.log

TS=`date "+%Y%m%d"`
FN="/tmp/mail.$TS.log"

cat - >> $FN
echo "=== End Of Message Received ===" >> $FN

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#!/bin/bash

# replace the /usr/bin/sendail with this shell script.

# Everytime someone sends a mail, the content of the mail will be written to a file under /tmp/mail.20150203.log

TS=`date "+%Y%m%d"`

FN="/tmp/mail.$TS.log"

cat - >> $FN

echo "=== End Of Message Received ===" >> $FN

sudo config

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sudo is a standard way to give users some administrative rights without giving out the root password. This can also be configured for non root users as well.

vi /etc/sudoers and add the following line
Syntax:
       user hosts = (runas) commands

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vi /etc/sudoers and add the following line

Syntax:

user hosts = (runas) commands

# user john is allowed to run some_script.sh as jack with no password
john ALL = (jack) NOPASSWD: /work/some_script.sh

1 2	# user john is allowed to run some_script.sh as jack with no password john ALL = (jack) NOPASSWD: /work/some_script.sh

# Any user part of the opsgrp will be allowed to mount and unmount squashfiles as root with no password.
User_Alias OPSACC = %opsgrp
OPSACC ALL = (root) NOPASSWD: /bin/mount -t squashfs -o loop *, /bin/umount -t squashfs *

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# Any user part of the opsgrp will be allowed to mount and unmount squashfiles as root with no password.

User_Alias OPSACC = %opsgrp

OPSACC ALL = (root) NOPASSWD: /bin/mount -t squashfs -o loop *, /bin/umount -t squashfs *

sftp only access (no shell access)

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groupadd sftponly_group
useradd -d /home/sftp_dir/ -g sftponly_group -s /bin/false sftp_user

1 2	groupadd sftponly_group useradd -d /home/sftp_dir/ -g sftponly_group -s /bin/false sftp_user

Add the following lines to /etc/ssh/sshd_config

Match Group sftponly_group
ChrootDirectory %h
AllowTcpForwarding no
X11Forwarding no
ForceCommand internal-sftp -l INFO -f AUTH

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Match Group sftponly_group

ChrootDirectory %h

AllowTcpForwarding no

X11Forwarding no

ForceCommand internal-sftp -l INFO -f AUTH

Make sure to restart sshd daemon.

Archives

mongoDB – under SUSE SLE11 – SP3

Hide/Show Desktop Icons on SUSE

Mojolicious

my .vimrc

LAMP – install on Ubuntu

Build & Install node.js from source code

jQuery Fundamentals

dummy sendmail

sudo config

sftp only access (no shell access)

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