Memorandums, Logbook & Shares

Wednesday, July 9, 2014

Google Map simple marker

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no">
<meta charset="utf-8">
<title>Geocoding service</title>
<style>
html, body, #map-canvas {
height: 100%;
margin: 0px;
padding: 0px
}
#panel {
position: absolute;
top: 5px;
left: 50%;
margin-left: -180px;
z-index: 5;
background-color: #fff;
padding: 5px;
border: 1px solid #999;
}
</style>
<script src="https://maps.googleapis.com/maps/api/js?v=3.exp"></script>
<script
src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
var geocoder;
var map;
function initialize() {
geocoder = new google.maps.Geocoder();
var latlng = new google.maps.LatLng(-34.397, 150.644);
var mapOptions = {
zoom: 8,
center: latlng
}
map = new google.maps.Map(document.getElementById('map-canvas'),
mapOptions);
}

var address_array =
[
"Shop 3-5, G/F, Po Fung Building, 1-7 Hop Yick Road, Yuen Long ",
"Rm 401, 4/F, Sincere House, 83 Argyle Street, Mong Kok ",
"Shop M001, Long Ping Commercial Complex, Long Ping Estate, Yuen Long ",
"Shop G06, G/F, Spot, 48 Lung Sum Avenue, Shek Wu Hui, Sheung Shui ",
"Unit 3, 2/F, United Success Commercial Centre, 508 Jaffe Road, Causeway
Bay "

];

count = 0
function codeAddress() {
//var address = document.getElementById('address').value;
var address = address_array[count];
if(typeof(address) == 'undefined') {
alert("Map completed.");
clearInterval(intervalID);
return;
}
geocoder.geocode( { 'address': address}, function(results, status) {
if (status == google.maps.GeocoderStatus.OK) {
map.setCenter(results[0].geometry.location);
var marker = new google.maps.Marker({
map: map,
position: results[0].geometry.location
});
} else {
if (status == google.maps.GeocoderStatus.OVER_QUERY_LIMIT) {
//alert("OVER_QUERY_LIMIT, just press ok to continue :) ");
count--;
} else {
the_index = address.indexOf(',');
if(the_index > 0) {
address_array.push(address.substring(the_index + 1,
address.length));
}
//alert('Geocode was not successful for the following reason: '
+ status);
//var error_messages = $('#messages').html() + status + " --- "
+ address + "<br/>"
//$('#messages').html(error_messages);
}
}
});
count++;
}

google.maps.event.addDomListener(window, 'load', initialize);

$(document).ready(function() {
//var intervalID = window.setInterval(codeAddress(), 1000);
start_map();
});

</script>
<script>

var intervalID;

function start_map() {
intervalID = window.setInterval(function(){codeAddress()}, 1000);
}

</script>

</head>
<body>
<div id="panel">

</div>
<div id="map-canvas" ></div>
<div id="messages" style='font-family:arial;' >The following
addresses cannot be marked: <br/></div>
</body>
</html>

Monday, June 23, 2014

Rails - Make Delayed job work with Rspec in tests

Turn off the queuing and let delayed job to run:

Delayed::Worker.delay_jobs = false

Friday, June 20, 2014

Rails override Time.now to return Time.zone.now

In initializer, add this:

class << Time
alias :system_now :now
def now
ActiveSupport::TimeWithZone.new(self.system_now.utc, Time.zone)
end
end

Tuesday, June 17, 2014

Nagios create plugins

On monitoring host:

Create plugin in /usr/lib/nagios/plugins (in C/Perl/Script/etc)
Enable plugin by:
1. define comment in /etc/nagios-plugins/config/somefile.cfg
2. edit /etc/nagios/conf.d/localhost_nagios2.cfg

Restart:
sudo service nagios3 restart

Thursday, June 12, 2014

Reviewed Ubuntu Server monitoring tools

Tried:
1. Nagios
2. Munin
3. Cacti
4. Zabbix

Turn out I like both Nagios and Zabbix.

Wednesday, June 11, 2014

Setup Nagios on Ubuntu 12.10

sudo apt-get update
sudo apt-get install nagios3 nagios-nrpe-plugin

If you have other web pages or apps running on the same server, the following information might be useful to separate Nagios as it's own Apache virtual host on a non-standard port (for example 43326 here).

Remove standard config and create Apache virtual host;

sudo cp /etc/apache2/conf.d/nagios.conf /etc/apache2/sites-available/nagio  s3  sudo rm /etc/apache2/conf.d/nagios.conf  sudo vi /etc/apache2/sites-available/nagios3

To beginning of file add;

Listen 43326  <VirtualHost *:43326>      ServerAdmin webmaster@localhost      DocumentRoot /var/www/nagios3

To the end of the file add;

</VirtualHost>

Enable the new site;

sudo a2ensite nagios3

If you run a firewall (UFW), open the port;

sudo ufw allow 43326

Restart Apache

sudo service apache2 restart

Ubuntu OS upgrade

http://www.cyberciti.biz/faq/howto-upgrade-to-ubuntu-14-04-from-ubuntu-13-10-or-12-04/

Linux system monitoring

http://www.linuxscrew.com/2012/03/22/linux-monitoring-tools/
http://www.tecmint.com/command-line-tools-to-monitor-linux-performance/
http://www.cyberciti.biz/tips/top-linux-monitoring-tools.html
http://www.thegeekstuff.com/2011/12/linux-performance-monitoring-tools/
http://www.opensourceforu.com/2013/12/look-top-three-network-monitoring-tools/

Tuesday, June 3, 2014

Tutorial resources

http://techtalk4us.blogspot.hk/2012/10/the-big-list-of-free-programming.html

Wednesday, May 21, 2014

Rails: Specify Time.zone in delayed job

Add the following code to the project's config/initializers/delayed_job.rb

The method_missing chain will add the current Time.zone.name to the
function's argument.

The Time.zone.name will be popped by the PerformableMethod.perform chain.

Delayed::DelayProxy.class_eval do

# Embed the current time zone name to delayed job's arguments when
# adding delayed job from delay() method.
def method_missing_with_custom_time_zone(method, *args)
raise "Time zone is nil" if Time.zone.nil?
args << {:custom_time_zone => Time.zone.name}
result = method_missing_without_custom_time_zone(method, *args)
result
end
alias_method_chain :method_missing, :custom_time_zone

end

Delayed::PerformableMethod.class_eval do

# Read time zone from job's argument.
def perform_with_custom_time_zone
if self.args.last.is_a?(Hash) &&
!self.args.last[:custom_time_zone].nil?
Time.zone = args.pop[:custom_time_zone]
else
raise "Custom time zone is missing from the arguments."
end
perform_without_custom_time_zone
end
alias_method_chain :perform, :custom_time_zone

end

Friday, May 16, 2014

Rails test with method that invoke delayed job

class Klass
def some_function
self.delay.time_consuming_function
end

def time_consuming_function
...
end
end

class KlassTest

test "some_function" do
Delayed::Job.all.each { |job| job.destroy }
Klass.new.some_function
Delayed::Job.all.each { |job| job.invoke_job }

assert ...
end

end

Monday, May 5, 2014

Postgresql server config files location

/etc/postgresql/[version]/main/

e.g. to set the listened port or location
/etc/postgresql/9.3/main/postgresql.conf

Wednesday, April 23, 2014

Function point analysis

http://alvinalexander.com/FunctionPoints/

Tuesday, April 22, 2014

Single sign on for web applications

Trial on Atlassian Crowd

current application on
1. Ruby on rails - using devise gem
2. Java EE application.

to be cont....

Thursday, April 3, 2014

Postgresql kill process

select * from pg_stat_activity;
select pg_cancel_backend([procpid]);

What if you revoke an SSL cert?

After revoke, client may see on firefox (may not be the case on Chrome):

To by-pass the checking in firefox, do this but not recommended:

Uncheck the checking option under validation button.

Thursday, March 6, 2014

Change crontab default editor

>select-editor

Tuesday, February 11, 2014

Ubuntu boot startup time log graph

BootCharting: https://wiki.ubuntu.com/BootCharting

Thursday, February 6, 2014

Toolbox - convert excel formula to asp.net

www.spreadsheetconverter.com

Check installed software on windows

wmic

wmic:root\cli>/output:C:\InstallList.txt product get name, version
wmic:root\cli>exit

Monday, January 20, 2014

Business Intelligence Tools - Jaspersoft

https://community.jaspersoft.com/download

Monday, January 6, 2014

Ubuntu: Change the waiting time on network configuration

/etc/init/failsafe.conf

Thursday, January 2, 2014

IT Director Responsibilities and Duties

IT Director Responsibilities and Duties

Coordinate with management in developing business strategic plans and operating policies.

Coordinate with business teams to analyze project contracts, proposals, requirements, and service level agreements.

Assist in developing project budgets and timelines.

Utilize project management experience to lead various global and regional projects.

Evaluate and revise project plan to meet changing project demands.

Manage project planning, staffing, schedule and expenses.

Oversee everyday project operations to ensure timely delivery.

Oversee the availability of application and infrastructure for project execution.

Identify and assign resources to IT projects.

Organize project status meetings with customers and team members.

Interact with customers to design and execute business solutions.

Ensure project deliverables meet highest quality standards and customer requirements.

Develop departmental standards and ensure that staffs adhere to these standards.

Provide analytical and technical assistance to project team.

Collaborate with management on application development, enhancement, and deployment activities.

Evaluate project proposals and change requests and make necessary recommendations for approval or rejection of proposals.

Tuesday, December 24, 2013

Revisit OOP fundumentals

Inheritance
Polymorphism
Abstraction
Encapsulation

Friday, December 13, 2013

Rails - Define class method in module file

module PicturePartials
module Cse

def self.included(base)
base.extend ClassMethods
end

module ClassMethods
def find_by_picture_id(picture_id)
Picture.joins(:picture).where('picture_id = ?', picture_id).first
end
end

end
end

Thursday, November 28, 2013

Ubuntu upgrade postgresql server from 8.4 to 9.2

backup database: pg_dumpall > dump.sql
http://wiki.postgresql.org/wiki/Apt

Create /etc/apt/sources.list.d/pgdg.list

Put this in the file:

deb http://apt.postgresql.org/pub/repos/apt/ [code]-pgdg main
where [code] can be found by lsb_release -c

wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -

sudo apt-get update
ps -C postgres
sudo apt-get purge postgresql-8.4
Create database user
Restore database
Done

Thursday, November 14, 2013

Restart network interface

sudo /etc/init.d/networking restart

Ubuntu find versions

uname -a (for kernel version)

lsb_release -a (for ubuntu version)

sudo fdisk -l (for partition info)

Tuesday, November 5, 2013

BI qlikview

www.qlik.com

Wednesday, October 23, 2013

Ubuntu start Tomcat on boot

Automatic Starting

To make tomcat automatically start when we boot up the computer, you can
add a script to make it auto-start and shutdown.

sudo vi /etc/init.d/tomcat

Now paste the following content:

# Tomcat auto-start
#
# description: Auto-starts tomcat
# processname: tomcat
# pidfile: /var/run/tomcat.pid

export JAVA_HOME=/usr/lib/jvm/java-6-sun

case $1 in
start)
sh /usr/local/tomcat/bin/startup.sh
;;
stop)
sh /usr/local/tomcat/bin/shutdown.sh
;;
restart)
sh /usr/local/tomcat/bin/shutdown.sh
sh /usr/local/tomcat/bin/startup.sh
;;
esac
exit 0
You'll need to make the script executable by running the chmod command:

sudo chmod 755 /etc/init.d/tomcat

The last step is actually linking this script to the startup folders
with a symbolic link. Execute these two commands and we should be on our
way.

sudo ln -s /etc/init.d/tomcat /etc/rc1.d/K99tomcat

sudo ln -s /etc/init.d/tomcat /etc/rc2.d/S99tomcat

Tuesday, October 15, 2013

Install webmin on Ubuntu

1. Download from http://www.webmin.com
2. sudo dpkg -i webmin_x.xxxx_all.deb (with error)
3. sudo apt-get install -f (will fix the error)
4. https://xxx.xxx:1000
DONE

Tuesday, October 8, 2013

diagnostic cap deploy permission denied public key

Problem:

xxxxx@xxxxx:~/RubyProjects/xxxxx$ bundle exec cap xxxxx deploy:migrations
/usr/local/rvm/gems/ree-1.8.7-2012.02@global/gems/bundler-1.1.4/lib/bundler/runtime.rb:211: warning: Insecure world writable dir /usr/local/rvm/gems in PATH, mode 042777
/usr/local/rvm/gems/ree-1.8.7-2012.02@global/gems/bundler-1.1.4/lib/bundler/runtime.rb:211: warning: Insecure world writable dir /usr/local/rvm/gems in PATH, mode 042777
* executing `xxxxx'
triggering start callbacks for `deploy:migrations'
* executing `multistage:ensure'
* executing `eighties_bands:ensure'
* executing `deploy:migrations'
* executing `deploy:update_code'
updating the cached checkout on all servers
executing locally: "git ls-remote git@xxxxx.unfuddle.com:xxx/xxxxx.git xxxxx-4"
command finished in 4746ms
* executing "if [ -d /home/xxxxx/deploy/shared/cached-copy ]; then cd /home/xxxxx/deploy/shared/cached-copy && git fetch -q origin && git reset -q --hard b40a43e351c2107de5c6bc8dae0c70de86465305 && git clean -q -d -x -f; else git clone -q git@xxx.unfuddle.com:xxx/xxxxx.git /home/xxxxx/deploy/shared/cached-copy && cd /home/xxxxx/deploy/shared/cached-copy && git checkout -q -b deploy b40a43e351c2107de5c6bc8dae0c70de86465305; fi"
servers: ["115.160.152.28"]
[115.160.152.28] executing command
** [115.160.152.28 :: err] Permission denied (publickey).
** [115.160.152.28 :: err] fatal: The remote end hung up unexpectedly
command finished in 13024ms
failed: "sh -c 'if [ -d /home/xxxxx/deploy/shared/cached-copy ]; then cd /home/xxxxx/deploy/shared/cached-copy && git fetch -q origin && git reset -q --hard b40a43e351c2107de5c6bc8dae0c70de86465305 && git clean -q -d -x -f; else git clone -q git@xxx.unfuddle.com:xxx/xxxxx.git /home/xxxxx/deploy/shared/cached-copy && cd /home/xxxxx/deploy/shared/cached-copy && git checkout -q -b deploy b40a43e351c2107de5c6bc8dae0c70de86465305; fi'" on 115.160.152.28

Reason:
git login failed on target machine.

Checkings:
ssh -v git@xxx.unfuddle.com

Check this on deployment machine and target server
If success, should see this: Authentication succeded (publickey).
If denied, will see this: debug1: Authentications that can continue: publickey
- This means the connection to git server is denied.

Solution:
On deployment machine,

ForwardAgent yes (.ssh/config)
Check if ssh-agent is running

ps aux | grep ssh

Add key to ssh:

ssh-add ~/.ssh/id_rsa

Check key:

ssh-add -l

Done

Wednesday, September 25, 2013

Ruby Json Indent Format

JSON.pretty_generate()

Tuesday, September 24, 2013

Change ubuntu apt-get mirror site

sudo vi /etc/apt/sources.list

deb http://ftp.cuhk.edu.hk/pub/Linux/ubuntu precise main restricted
universe multiverse
deb-src http://ftp.cuhk.edu.hk/pub/Linux/ubuntu precise main restricted
universe multiverse

deb http://ftp.cuhk.edu.hk/pub/Linux/ubuntu precise-updates main
restricted universe multiverse
deb-src http://ftp.cuhk.edu.hk/pub/Linux/ubuntu precise-updates main
restricted universe multiverse

:wq

sudo apt-get update

(e.g.) sudo apt-get install maven

Allow remote access to postgres sql

edit /etc/postgresql/9.1/main/postgresql.conf

listen_address = '*'

edit /etc/postgresql/9.1/main/pg_hba.conf

replace the config with:

host all all 0.0.0.0/0 md5

Check 32 bit or 64 bit Ubuntu version

uname -a

Result for 32-bit Ubuntu:

Linux discworld 2.6.38-8-generic #42-Ubuntu SMP Mon Apr 11 03:31:50 UTC
2011 i686 i686 i386 GNU/Linux

whereas the 64-bit Ubuntu will show:

Linux discworld 2.6.38-8-generic #42-Ubuntu SMP Mon Apr 11 03:31:50 UTC
2011 x86_64 x86_64 x86_64 GNU/Linux

Friday, September 6, 2013

Revisit Java deadlock

Java deadlock:
http://javarevisited.blogspot.hk/2010/10/what-is-deadlock-in-java-how-to-fix-it.html

Wednesday, September 4, 2013

Backup postgresql using pgdump

>sudo su - postgres
>pg_dump some_database_name > somename.sql

Wednesday, August 28, 2013

Ubuntu bash check opened port

sudo netstat -anltp

Tuesday, August 13, 2013

Wireframe tool

http://balsamiq.com/

Tuesday, August 6, 2013

Technical - Mulesoft ESB vs Talend

http://www.slideshare.net/KaiWaehner/spoilt-for-choice-how-to-choose-the

Tuesday, July 23, 2013

Mysql dump backup and restore all database

Backup:

mysqldump --flush-privileges --all-database -p > mysqldump.all.database.20130723.sql

Restore:

mysql -u root -p < mysqldump.all.database.20130723.sql

Monday, July 22, 2013

Solved: apt-get install 404 Not Found

sudo apt-get update

Solve: apache You don't have permission to access / on this server

In httpd.conf

<Directory />
    #Options FollowSymLinks
    Options Indexes FollowSymLinks Includes ExecCGI
    AllowOverride All
    Order deny,allow
    Allow from all
</Directory>

Tuesday, May 7, 2013

EaseUS - windows partition tools

http://www.easeus.com/

Thursday, May 2, 2013

Ubuntu change name/ hostname

# vim /etc/hostname
內容改為自己要的名字

# vim /etc/hosts
這邊最好也要改，免得有些 service 會出錯

# /etc/init.d/hostname.sh or # sudo service hostname restart
重新啟動

# hostname
驗證是否已經修改完畢。

Tuesday, April 30, 2013

postgresql create drop user

Postgresql server start

Use the following command (from terminal) to control the PostgreSQL server
Start the service : /etc/init.d/postgresql start
Stop the service : /etc/init.d/postgresql stop
Know the status : /etc/init.d/postgresql status
Restart the service : /etc/init.d/postgresql restart

Read more: http://linuxpoison.blogspot.tw/2012/01/how-to-install-configure-postgresql.html#ixzz2RutcjeNH

Thursday, April 25, 2013

ubuntu fix ip

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

File: /etc/network/interfaces

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet static

address 192.168.8.188
netmask 255.255.255.0
network 192.168.0.0
broadcast 192.168.0.225
gateway 192.168.8.1
dns-nameservers 192.168.8.201 202.130.97.65

sudo /etc/init.d/networking restart

mac hosts file

sudo vi /private/etc/hosts

Install apache for ruby on rails on Ubuntu

Install apache2

sudo apt-get update
sudo apt-get install apache2

Enable https

sudo a2enmod ssl
sudo a2ensite default-ssl

sudo service apache2 restart

Install Passenger

gem install passenger
passenger-install-apache2-module
sudo apt-get install libcurl4-openssl-dev
rvmsudo rvm get head && rvm reload && rvm repair all
Permission denied -> chmod 777...

Install passenger on ubuntu

Ubuntu: Curl development headers with SSL support

By: Richard26-11-2010computing
Share
Just been trying to install Passenger on a new Ubuntu EC2 instance and
passenger is giving me the error:

* Curl development headers with SSL support... not found

Took some digging around but turns out I was just missing the
libcurl4-openssl-dev package:

sudo apt-get install libcurl4-openssl-dev

Solve Apache2 permission problem.

<Directory />
    Options FollowSymLinks
    AllowOverride All
    Order deny,allow
    Allow from all
</Directory>

Monday, April 15, 2013

vim binary mode

To binary mode -- :%!xxd
To normal mode -- :%!xxd -r

Sunday, April 14, 2013

Git move master to branch

git checkout target_branch
git merge --strategy==ours --no-commit master
git commit -m "Move master to this branch..."
git checkout master
git merge target_branch

Git command history

>git reflog

Friday, April 5, 2013

Linux - Bash encrypt and decrypt file

openssl des3 -salt -in unencrypted-data.file \
-out encrypted-data.file.des3

openssl des3 -d -salt -in encrypted-data.file.des3 \
-out unencrypted-data.file

Thursday, March 14, 2013

Mysql - backup all databases

$ mysqldump -u root -p --all-databases > alldb_backup.sql

Wednesday, March 13, 2013

Migrate Atlassian Confluence local version 4.0 to OnDemand version 5.0

Backup current wiki data to XML.
Upgrade local 4.0 to 5.0 version.
Subscribe Confluence OnDemand service.
Export space from local wiki, one by one, since OnDemand version cannot restore the whole backup in one click.
Import spaces to OnDemand.
Done.

Tuesday, March 12, 2013

Mac reset password

1. Press and Hold Command-R when startup.
2. Open terminal.
3. >resetpassword

Friday, March 8, 2013

Windows 7 hosts file

C:\Windows\System32\driven\etc\hosts

Thursday, March 7, 2013

Git - remove or delete tag and remote tag

git tag -d 12345  git push origin :refs/tags/12345

Monday, March 4, 2013

Rails - update attr_readonly field from sql

The easiest way to update field with attr_readonly is to update by
database sql.

$> psql -d xxx -U xxx
xxx> update ... set ... where ...

Wednesday, February 27, 2013

Rails - Cap deploy solve the problem on Permission denied (publickey)

Run "$>ssh-add" to add private key identities to authentication agent.
Solved.

Thursday, February 21, 2013

Rails - Caution on adding new column and assign value to it in the same db migration - reset_column_information

This happens on staging/production rails env.

If you add a new column 'xxx' and assign value to it in the same migration,

Then, you may get error like this: undefined method 'xxx'

You should do a column reset after add column:

e.g. User.reset_column_information

Wednesday, February 20, 2013

Rails - check routes in rails console

puts Rails.application.routes

Rails - Functional test directly calls the controller without using the routes.rb

Note that the functional tests bypass the router will not capture the
effect of changing HTTP verb.

Rails - List all routes

rake routes

Tuesday, February 19, 2013

selenium ide - AssertConfirmation wildcard *

AssertConfirmation *

Postgresql - show version

psql --version

OR

postgres=# select version();

Postgresql - list users

\du

Git global config

git config --global user.name "Your Name"
git config --global user.email you@example.com

git config --global color.diff auto
git config --global color.status auto
git config --global color.branch auto
git config --global color.log auto

Mac enable root user

How to enable the root user

OS X Lion

From the Apple menu choose System Preferences....
From the View menu choose Users & Groups.
Click the lock and authenticate as an administrator account.
Click Login Options....
Click the "Edit..." or "Join..." button at the bottom right.
Click the "Open Directory Utility..." button.
Click the lock in the Directory Utility window.
Enter an administrator account name and password, then click OK.
Choose Enable Root User from the Edit menu.
Enter the root password you wish to use in both the Password and Verify fields, then click OK.

http://support.apple.com/kb/HT1528?viewlocale=en_US

Monday, February 18, 2013

Edit hosts file on Mac OS

$> sudo vi /private/etc/hosts

115.160.xxx.12 staging
115.160.xxx.11 production

Friday, February 15, 2013

Rails - Solved - relation 'xxx' does not exist

ActiveRecord::StatementInvalid: PGError: ERROR: relation "xxx" does not
exist
LINE 1: DELETE FROM "xxx"
^
: DELETE FROM "xxx"

Solution:

Remove test/fixture/xxx.yml if exists.

Friday, February 1, 2013

Mac system log

tail -f /var/log/system.log

Wednesday, January 30, 2013

Web - Resources on File Upload

http://blueimp.github.com/jQuery-File-Upload/

http://swatelier.info/at/forms/file.htm

http://www.uploadify.com/

Monday, January 28, 2013

Ruby - Excel Spreadsheet

http://spreadsheet.ch/

Friday, January 25, 2013

Java Garbage Collection

PermGen, Garbage collection.

http://blog.takipi.com/garbage-collectors-serial-vs-parallel-vs-cms-vs-the-g1-and-whats-new-in-java-8/

RMI -> Web services
Servlet, Applet, JSP -> Spring

Thursday, January 24, 2013

Ruby - Catch or rescue multiple exceptions on the same line.

begin
...
rescue ExceptionType1, ExceptionType2 => e
...
end

Friday, January 11, 2013

Management - Request agile developer to submit a feature spec and design spec before beginning a new story

In an agile development environment, developer will collect story owner feature requirement and then design the way to implement. To overview the job to be carry out by developer, team leader have to get a sense of what has been requested and what is being prepared and designed.

Git - Find changes of a file within all local branches

git log --all -- somefile_fullpath

Thursday, January 10, 2013

Practice - Keep a source code map in wiki

For new joined developers to quickly locate the source code.

Tuesday, January 8, 2013

Linux - rsync from local to remote

rsync -au /var/www/confluence/confluence-data/backups -e 'ssh -p 1337' your_name@some_ip:/home/your_name/backups/wiki_backups

Monday, January 7, 2013

Development steps for Facebook integration - website app

Register a Facebook account.
Register as a Facebook developer.
Create new app.
Follow samples or demo on Facebook site.

References:
http://developers.facebook.com/docs/guides/web/
https://www.facebook.com/help/403653596349195/
https://developers.facebook.com/apps
https://developers.facebook.com/docs/guides/appcenter/
http://developers.facebook.com/docs/samples/

Saturday, January 5, 2013

Apache supporting multiple domain websites with single IP

Listen 443
NameVirtualHost *:443
SSLStrictSNIVHostCheck off
<VirtualHost *:443>
DocumentRoot /srv/www/example1.com/
ServerName www.example1.com
...
</VirtualHost>
<VirtualHost *:443>
DocumentRoot /srv/www/example2.com/
ServerName www.example2.com
...
</VirtualHost>

Thursday, January 3, 2013

Create a SSL Cert, sign by Godaddy.com, install on Apache

Login VPS, root@ubuntu:~# openssl req -new -newkey rsa:2048 -nodes -keyout your_domain.key -out your_domain.csr
Godaddy.com

Product > SSL Cert

Basic SSL Cert
3 yrs

Add to cart
Checkout
Payment
Account > SSL Cert

Setup
Launch

Current Certificates

Credits

Refresh

Request Certificate

Choose 3rd party
Paste your_domain.csr content to form
submit

Wait for email.
Download cert from Godaddy.com.

Select Apache.

Copy your_domain.crt and gd_bundle.crt (the CA's bundle file) to VPS, e.g. /etc/ssl/private/
Edit /etc/apache2/sites-available/default.ssl

SSLCertificateFile /etc/ssl/private/your_domain_com.crt
SSLCertificateKeyFile /etc/ssl/private/private.key
SSLCACertificateFile /etc/ssl/private/gd_bundle.crt

Restart apache. $> sudo service apache2 restart
Done

References:
http://support.godaddy.com/help/article/5269/generating-a-certificate-signing-request-csr-apache-2x
http://support.godaddy.com/help/article/562/requesting-standard-and-wildcard-ssl-certificates
http://support.godaddy.com/help/article/5238/installing-an-ssl-certificate-in-apache

https://help.ubuntu.com/12.04/serverguide/httpd.html
http://www.geocerts.com/install/apache_2

Tuesday, January 1, 2013

Toolbox - Zabbix

Zabbix is the ultimate open source availability and performance
monitoring solution. Zabbix offers advanced monitoring, alerting, and
visualization features today which are missing in other monitoring
systems, even some of the best commercial ones.

Monday, December 31, 2012

Selenium - Get current date

<tr>
        <td>storeEval</td>
        <td>var d=new Date(); d.getDate()+'-'+((d.getMonth()+1))
+'-'+d.getFullYear();</td>
        <td>date2</td>
</tr>
<tr>
        <td>echo</td>
        <td>${date2}</td>
        <td></td>
</tr>

Rails solved - Capistrano change repository

Remove deploy/shared/cached-copy
(remove .ssh/known_hosts) <- optional
ssh git@xxx.unfuddle.com
(config.rb add: default_run_options[:pty] = true) <- optional

Reference: https://help.github.com/articles/deploying-with-capistrano

Known Hosts bug

If you are not using agent forwarding, the first time you deploy may fail due to Capistrano not prompting with this message:

# The authenticity of host 'github.com (207.97.227.239)' can't be established.
# RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48.
# Are you sure you want to continue connecting (yes/no)?
To fix this, ssh into your server as the user you will deploy with, run ssh git@github.com and confirm the prompt.

Sunday, December 30, 2012

Git tips - create an empty commit

git commit --allow-empty -m '[empty] initial commit'

Git tips - search a string on all revisions

git rev-list --all | (
while read revision; do

git grep -F 'Your search string' $revision

done

)

Friday, December 28, 2012

Linux - use rsync to backup local directory

$> rsync -au /home/source /home/target

Tuesday, December 25, 2012

Cloud server vs VPS

http://forums.eukhost.com/f45/cloud-server-vs-vps-virtual-private-server-11356/#.UNkQBpNevKw

2010

Cloud hosting offers many advantages over normal VPS or Semi-Dedicated server hosting services due to the number of servers that are being used for a single cluster, and if you or your business rely greatly on your website, Cloud hosting is the best suitable option for you. The enhanced architecture powering Cloud hosting solution utilize groups of high specification servers, network attached storage devices to reliably serve every web page, and image of a website. Inside each storage device, drives are replicated to each other in a RAID configuration to create a first level of redundancy.

With Virtual Private server, you will not get guaranteed resources that you will pay for, which means other user of the VPS node could squeeze in on your allotted resources but this is not case with Cloud server, you will get the guaranteed amount of resources you are paying for and it's always available when you need them. In addition to all these features, you will also get the ability to customize the resources of Cloud server anytime. VPS is not at all reliable when compared to Cloud server because VPS is based on software virtualization platform. Each platform of servers have their merits and demerits but here there are no demerits of Cloud server, so now it depends on you whether to choose VPS or Cloud server after understanding the needs and the service that you are looking.

http://www.vps.net/blog/2012/08/20/vps-vs-cloud-server/

Cloud Servers have three primary advantages over a traditional VPS.

Near limitless flexibility with resource sizes.
On the fly resource upgrades, sometimes without even requiring a reboot.
Significantly better redundancy
Centralized redundant storage

VPS - not quite reliable on stability

Today, our web hosting on VPS is down. Called the technical support for
the reason saying that VPS down is common.

Mac shortcut symbols

	Command/Apple Key (like Control on a PC) Also written as Cmd
	Option (like Alt on a PC)
	Shift
	Control (Control-click = Right-click)
	Tab
	Return
	Enter (on Number Pad)
	Eject
	Escape
	Page Up
	Page Down
	Home
	End
	Arrow Keys
	Delete Left (like Backspace on a PC)
	Delete Right (also called Forward Delete)

reference: http://www.danrodney.com/mac/index.html

Monday, December 24, 2012

Ruby - Notes on using Yardoc

List Options
$> yard help doc

Add additional tags:

>$ yardoc --tag data_source:"Data Source"
where data_source is the tag in comment. e.g. # @datasource The data is gathered by client collection.
"Data Source" is the string that appears on the generated document.

OR

Create a .yardopts file in project root, add the line --tag data_source:"Data Source"
Then >$yardoc

https://rubydoc.tenderapp.com/kb/getting-started-with-rubydocinfo/setting-up-a-yardopts-file