Friday, October 26, 2018

How to configure ssh login with out password in Mac OS X and Linux


When ever we want to connect to remote server (or) host using SSH we will provide the host name after it prompt for password. If we follow the below step it won't ask for the password on each time.
ssh password less login


STEP 1 - Generating the key pair

Create your set of keys:
Start up the Terminal application and run:
ssh-keygen -t rsa -b 4096



STEP2 - Copy Generated public to our remote server


Copy the newly created public key to the SSH server(s) you need to auto login into by using your favourite transport method.

Please be careful not to overwrite ~/.ssh/authorized_keys if it already exist! This is how I personally copy the key, might not be your preferred method:

If authorized_keys exist:
cat ~/.ssh/id_rsa.pub | ssh username@example.com "cat - >> ~/.ssh/authorized_keys"
If authorized_keys does not exist:
scp ~/.ssh/id_rsa.pub username@example.com:~/.ssh/authorized_keys


Check your file permissions. A lot of different *nix system is picky when it comes to permissons. Setting your .ssh directory to 0700 and .ssh/authorized_keys to 0600.

  chmod 0700 ~/.ssh
  chmod 0600 ~/.ssh/authorized_keys

Tuesday, May 29, 2018

Read the data from server using Backbone js collection fetch data







Linux-Shell Script to Move to specific folder using "cd" command




Shell scripts are run inside a subshell, and each subshell has its own concept of what the current directory is. The cd succeeds, but as soon as the subshell exits, you're back in the interactive shell and nothing ever changed there.

To Resolve that we use bash command. 




#!/bin/sh
#!/bin/bash

cd "/opt/azw/webapp/src/";
bash



Thursday, January 4, 2018

To pull specific directory with git


To pull specific folder from git repository or git repo

mkdir directoryName
cd directoryName
git init
git remote add origin -f <>
git config core.sparsecheckout true
echo / >> .git/info/sparse-checkout
git pull origin master




Monday, October 16, 2017

Python Cheat Sheet

Python Cheat Sheet





Friday, October 6, 2017

Connect to Microsoft SQL Server Using PHP

Connect to Microsoft SQL Server Using PHP


Below Code will connect to the Microsoft Sql Server using php script.

Thursday, September 21, 2017

Authenticating with OAuth 2.0 For LinkedIn Api Access using PHP

Authenticating with OAuth 2.0 For LinkedIn Api Access using PHP


LinkedIn Oauth 2.0 PHP Access


Follow these steps to enable your application to make
authenticated API calls to LinkedIn using OAuth 2.0:


Step 1: Configuring your LinkedIn application.

Create application in linkedin Developers Panel Link.

After Clicking on Create App. Fill the form information.


Once you save your configuration, your application will be assigned a unique "Client ID"   and "Client Secret" value.


Step2: Using the below PHP code to get the LinkedIn access Token to access there apis







Friday, September 8, 2017

Reading Excel Spreadsheets with Python

Excel & Python

Reading an Excel Spreadsheet

In this section, we will look at a function that demonstrates reads the Excel sheet data and convert that data into XML file.

We Used the following libraries to do the above functionality


  • Openpyxl : Openpyxl is a Python library for reading and writing Excel 2010 xlsx/xlsm/xltx/xltm files.
  • xml.etree.ElementTree: To create the xml tree elements
  • datetime: to conver the date time column values to specified format 


Thursday, September 7, 2017

PHP popen() Function

popen in php

Parallel processing in PHP Using popen() Function


Since PHP does not offer native threads, we have to get creative to do parallel processing.
There will be scenarios where PHP takes much time to complete a task. Example scenarios are attaching a large file and and sending an email, or processing a large video file 
to make thumbnails. Imagine  a user having to wait until PHP finishes the all that job.

All the heavy work might being going on at the server. 
But, if a user doesn't see any activity on a page for some time, they might think that the page is not working and leave the page.  In such cases, we can make use of a background process.


Example of popen as a Async processing


Make popen as synchronous

The below code will wait until child process completed.
echo date("h:i:s");echo "\n";
$ph = popen('php ' . $commandName , 'r') or die($php_errormsg);
while (! feof($ph)) {
$s = fgets($ph) or die($php_errormsg);
}
pclose($ph) or die($php_errormsg);
echo date("h:i:s");echo "\n";

Friday, September 1, 2017

Install mysql-python in windows



To Enable the mysql extension related python need to run the below command
pip install mysqlclient




If you are trying to use mysqlclient on WINDOWS with this failure,

   "_mysql.c(29) : fatal error C1083: Cannot open include file: 'my_config.h': N
 such file or directory"

try to install the lower version instead:

pip install mysqlclient==1.3.4

Configure Apache web server for Python on Windows

Run Python script as CGI program with Apache2.4 in Windows


1. Install Python and Apache

Python: http://python.org/download/.

Apache: http://httpd.apache.org/download.cgi


2. Configure Apache to run Python CGI

The next step is to edit ‘httpd.conf’ apache configuration file located in the apache
install directory in the conf directory.

Uncomment the below line
#LoadModule cgi_module modules/mod_cgi.so

After Uncomment
LoadModule cgi_module modules/mod_cgi.so

Search the httpd.conf file for the line

Options Indexes FollowSymLinks

Add ExecCGI to the end of the line. After adding total line looks like below

Options Indexes FollowSymLinks ExecCGI

Next, search for the following:

#AddHandler cgi-script .cgi

Uncomment this line by removing the # in front of the line,
and add a .py to the end of the line. The new line should look like this:


 AddHandler cgi-script .cgi .py



Search for the line: ScriptAlias /cgi-bin/ /whatever-path/ – when you find it,
comment out the line: that is add a # in front of the line:
(or)Other wise add the below line

ScriptAlias /cgi-bin/ "C:/Apache2.4/cgi-bin/"


3. Restart Apache


4. Run the sample python file

Here is an example assuming Python is installed in the C:\Python27 location



Save this file as test.py to your htdocs folder under your apache installation directory.
Open your web browser and type in your apache host
(and :port if the port is something other than 80) followed by test.py,
for example:   http://localhost/test.py

PHP Array insert, delete, view operation using php array functions

PHP Array Functions

Insert the array element, View the array values and delete the array value using php array functions
Function Name Description
array_search() Searches an array for a given value and returns the key
array_splice() Removes and replaces specified elements of an array


Sample php array functions code



Friday, August 4, 2017

Asterisk Call Originate Action Using Pami

asterisk

What is Asterisk?

Asterisk is an open source framework for building communications applications. Asterisk turns an ordinary computer into a communications server. Asterisk powers IP PBX systems, VoIP gateways, conference servers and other custom solutions. It is used by small businesses, large businesses, call centers, carriers and government agencies, worldwide. Asterisk is free and open source.

About PAMI

PAMI means PHP Asterisk Manager Interface. It is an OOP client for the Asterisk Manager Protocol, implemented in PHP.

About PAMI Features

  • TCP and TLS connections.
  • Event Driven (the framework will dispatch events to your listener).
  • Lightweight, easy of use, and useful.
  • Supports synchronous and asynchronous events (Actions with Responses, and 
  • Responses with Events associated).
  • Supports SMS via VGMS boards.


Tuesday, July 18, 2017

Getting Started with Redis in PHP

What is Redis?

Redis created by Salvatore Sanfilippo is an open source, in-memory data structure server with advanced key-value cache and store, often referred to as a NoSQL database. It is also referred to as a data structure server, since it can store strings, hashes, lists, sets, sorted sets, and more.

The essence of a key-value store is the ability to store some data, called a value inside a key. This data can later be retrieved only if we know the exact key used to store it.

Usage of Redis

  • Caching can be used in the same manner as memcached.
  • Leaderboards or related problems.
  • Counting stuff.
  • Real time analysis.
  • Deletion and filtering.
  • Show latest item listings in your home page.

Install on Windows

Now, let us check how to set up Redis PHP driver.

You need to download the phpredis from github repository https://github.com/nicolasff/phpredis. Once you’ve downloaded it, extract the files to phpredis directory.

extension = redis.so

Connect to Redis Server


Monday, July 17, 2017

Inter Process Communication Using PHP ,ZeroMQ AND React/ZMQ

push the external changes to existing web pages

The above diagram shows the any external php file or database layer changes has happen should be notify to all our web client. We can able to achieve this using React/ZMQ

Requirements

ZeroMQ

All Our client web pages will be listening to port 8080 for incoming WebSocket connections...but how will it also get updates from another PHP script or another server process event. Enter ZeroMQ. We could use raw sockets, like the ones Ratchet is built on, but ZeroMQ is a library that just makes sockets easier. install zmq

React/ZMQ

Ratchet is a WebSocket library built on top of a socket library called React. React handles connections and the raw I/O for Ratchet. In addition to React, which comes with Ratchet, we need another library that is part of the React suite: React/ZMQ. This library will bind ZeroMQ sockets to the Reactor core enabling us to handle both WebSockets and ZeroMQ sockets. To install, your composer.json file should look like this:

To Run the above application go to root directory "push" run below command to run the web socket connection on server side
php bin/push-server.php
Run the : "push\src\MyApp\clientwebpage.html" which connect to web socket listen to the specified category

PHP ZMQ extension Installation in Apache 2.4 & php 5.6


PHP ZMQ extension we will look at how you can easily distribute work to background processes, provide flexible service brokering for your next service oriented architecture, and manage caches efficiently and easily with just PHP and the ZeroMQ libraries. Whether the problem is asynchronous communication, message distribution, process management or just about anything, ZeroMQ can help you build an architecture that is more resilient, more scalable and more flexible, without introducing unnecessary overhead or requiring a heavyweight queue manager node..

Installing ZMQ in Windows

Required Softwares Apache 2.4 & PHP 5.6
  1. Download the zmq php extension from following url depends up on the installed php version
    url: ZMq Download Url
  2. Extract the folder
  3. Copy the php_zmq.dll to php/ext directory
  4. Then copy the libzmq.dll to the php/ root directory
  5. Add below line in php.ini file : extension=php_zmq.dll

Friday, April 7, 2017

Defining a HTML template to append using JQuery

Append Dynamic content to html template using Jquery

If we want to append the dynamic content to html template using jquery below will be the simple solution

Wednesday, April 5, 2017

Iframe communication or Accessing a cross-origin frame

Accessing a cross-origin frame.

window.postMessage allows you to send messages not only across frames (regular frame or iframe) but also across domains. This post showed interaction from parent to child. Even when we keep the iframe domain url is different for the main page url.
With out using the window.postMessage will gives us below error message in console

SecurityError: Blocked a frame with origin from accessing a cross-origin frame

You can't access an iframe with Javascript, it would be a huge security flaw if you could do it.
For the same-origin policy browsers block scripts trying to access a frame with a different origin.
Origin is considered different if at least one of the following parts of the address isn't maintained: ://:/path/to/page.html Protocol, hostname and port must be the same of your domain, if you want to access a frame.


Examples
Here's what would happen trying to access the following URLs from http://www.example.com/home/index.html

URL RESULT
http://www.example.com/home/other.html -> Success
http://www.example.com/dir/inner/another.php -> Success
http://www.example.com:80 -> Success (default port for HTTP)
http://www.example.com:2251 -> Failure: different port
http://data.example.com/dir/other.html -> Failure: different hostname
https://www.example.com/home/index.html.html -> Failure: different protocol
ftp://www.example.com:21 -> Failure: different protocol & port
https://google.com/search?q=james+bond -> Failure: different hostname & protocol
Workaround

Monday, April 3, 2017

Get Google contacts with Javascript using Google Contacts API and OAUTH 2.0

To get the Google Contacts with Javascript using Google Contacts Api

To Pull the google contacts we need to create a project in google developer console

Create a Google application in Google Developers Console for obtaining your Client id and Client secret

  • Go to Google Google Developers Console and login with your google account.
  • create one a project by clicking Create Project Button
  • Go into the newly created project
  • Click On the Menu icon and select the Api Manager Link
  • Search for “Contacts API” and click on it
  • Enable the “Contacts API” by hitting the “Enable API” button
Below is the code to pull the contacts from google relplace client id with newly created client id