How to Change Timezone in CentOS

You check the time from the command line (run date), and find that the timezone is set to UTC or some other timezone. How do you get this changed?
To change this you have to have root access to the server.

There are a series of time zone files located at /usr/share/zoneinfo. Select the appropriate named timezone for your location. For my location I would need , Kolkata, Asia.

Make note of the appropriate folder and file for your timezone. The active timezone used on your system is in the /etc/localtime file.

First, make a backup of the existing localtime file. It’s always safe to make backups of original config files.

sudo mv /etc/localtime /etc/localtime.bak_01012015

Next, create the link:

sudo ln -s /usr/share/zoneinfo/Asia/Kolkata /etc/localtime

To test your change run the date command. You will see the new time.

Timezone issue with cron

If your cron job timing does’t match with the server time zone for example. You have set the cron to run at 12:30 PM, but when you see the cron log the time show say 3:40 PM. So to run your cron job as per your time zone Say if you are in India, your cron job should run as per Indian time. So you have to add the following line before your cron job line.

CRON_TZ=”Asia/Kolkata” ## This is the important line
03 18 * * * wget http://www.abc.com/test.php >> /var/www/html/abc/logs/test-`date +\%Y\%m\%d`.log

`date +\%Y\%m\%d` => This will create the log as per date month and year wise. Date format enclosed by tick (`) sign

Force HTTPS url with .htaccess

RewriteCond %{HTTPS} off
# First rewrite to HTTPS:
# Don’t put www. here. If it is already there it will be included, if not
# the subsequent rule will catch it.
RewriteRule .* https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
# Now, rewrite any request to the wrong domain to use www.
RewriteCond %{HTTP_HOST} !^www\.
RewriteRule .* https://www.%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

create high quality video using ffmpeg

You can use the open source ffmpeg program to convert a media file from low quality to high quality format

[shellprompt]# /fullpath/to/ffmpeg/ffmpeg -i source.mp4 -c:v libx264 -crf 19 destinationfile.flv

OR

[shellprompt]# /fullpath/to/ffmpeg/ffmpeg -i source.mp4 -c:v libx264 -ar 22050 -crf 28 destinationfile.flv

Parameter explained
-crf XX is the quality of the video you are looking for. It’s between 0 and 51 (but between 17 and 23 it’s a reasonable range and the lowest the number is, the better quality the video is going to be).

For the -ar 22050 it’s for adjusting the audio sample range (audio quality). You can choose 11025, 22050 or 44100.

For many other example and details explanation refer Tutorial for FFMPEG

convert video from one format to another using ffmpeg

You can use the open source ffmpeg program to convert a media file from one format to another.

Below is an exmple:

[shellprompt]# /fullpath/to/ffmpeglibrary/ffmpeg -i InputFile.FLV OutputFile.mp3

There are various other options you can use to specify the attribute of the output file.

Here are few of the examples code http://linuxers.org/book/export/html/593

create video thumbnail using ffmpeg

You can use the open source ffmpeg program to extract a frame to use as a thumbnail for a video.

Below is an exmple:

[shellprompt]# /fullpath/to/ffmpeglibrary/ffmpeg -i InputFile.FLV -vframes 1 -an -s 400×222 -ss 30 OutputFile.jpg

-i = Inputfile name
-vframes 1 = Output one frame
-an = Disable audio
-s 400×222 = Output size
-ss 30 = Grab the frame from 30 seconds into the video

Set widget label from action file in symfony 1.4

In Action File

==========================================================

$this->form = new youFormclassname();

To set individual Label

$this->form->getWidget(‘widgetname’)->setLabel(‘widget Custom label’);

To set multiple field label

$this->form->getWidgetSchema()->setLabels(array(
‘field_name_1’    => ‘Field 1 Custom Lable’,

‘field_name_2’    => ‘Field 2 Custom Lable’,

}

++++++++++++++++++++++++++++++++++++++

In Template File

============================================

<?php echo $form[‘field_name_1’]->renderLabel() ?>

Replace any text from html text by tag name with specific attribute in php

function replace_tag_with_specific_attr_type( $tagAttribute, $tagAttributeValue, $subjectStr, $tagName=null,$replaceStr ) {
if( is_null($tagName) )
$tagName = ‘\w+’;
else
$tagName = preg_quote($tagName);

$tagAttribute = preg_quote($tagAttribute);
$tagAttributeValue = preg_quote($tagAttributeValue);

$match_regex = “/<(“.$tagName.”)[^>]*$tagAttribute\s*=\s*”.
“([‘\”])$tagAttributeValue\\2[^>]*>(.*?)<\/\\1>/”;

preg_match_all($match_regex,
$subjectStr,
$matches,
PREG_PATTERN_ORDER);

$result = str_replace($matches[3],$replaceStr,$subjectStr);
return $result;
}

Usage :
Say for Example

$ActualStr : ‘<div class=’bannerpicsd’ ><span style=”margin: 0px 0px 0px 0px; width: 540px;”>something</span><p style=”float: right; margin: -240px 0 0; width: 200px;”>This is the actual String</p></div>’;
$StrToReplaceWith = ‘This is the replaces str’;

Now you want to replace all the text inside the div tags with class name “bannerpicsd”  from $ActualStr with $StrToReplaceWith
Then you can do as below:

$replacedStr  = replace_tag_with_specific_attr_type(‘class’,’bannerpicsd’,$ActualStr,’div’,$StrToReplaceWith);
Result :
<div class=”bannerpicsd” >This is the replaces str</div>
Enjoy 🙂

Replace any text from html text by tag name in php

function replace_tag_text($tagName,$subjectStr,$replaceStr) {
$tagName = preg_quote($tagName);
preg_match_all(‘{<‘.$tagName.'[^>]*>(.*?)</’.$tagName.’>}’,$subjectStr,$matches,PREG_PATTERN_ORDER);
$result = str_replace($matches[1],$replaceStr,$subjectStr);
return $result;
}

Usage :
Say for Example

$ActualStr : ‘<div><span style=”margin: 0px 0px 0px 0px; width: 540px;”>something</span><p style=”float: right; margin: -240px 0 0; width: 200px;”>This is the actual String</p></div>’;
$StrToReplaceWith = ‘This is the replaces str’;

Now you want to replace all the text inside the <div> tags from $ActualStr with $StrToReplaceWith
Then you can do as below:

$replacedStr  = replace_tag_text(‘div’,$ActualStr,$StrToReplaceWith);
Result : <div>This is the replaces str</div>

Enjoy 🙂