annoying problem with firefox 21 on mac

firefox used to minimize itself when you double click on the title bar, but with firefox 21 release, it does not behave any more. it seems that firefox app did not implement double mouse click handler.

switching to chrome unless firefox bring back this.

sql fundation

two bases for sql: set theory and predicative logic

filter on current date and passing time

Table meeting has start and end time field and to select all meetings for today and exclude meetings finished two hours ago.

select * from meeting
where convert(date, start) = convert(date, getdate())
and cast(start-getdate() as float)*24*60 < -120

Embed XML file in Flex application

[Embed(source="../assets/usa_tsa.kml", mimeType="application/octet-stream")]
private var tsaKml:Class;

…

var byteArray:ByteArray = new tsaKml() as ByteArray;
var xml:XML = new XML(byteArray.readUTFBytes(byteArray.length));

...

Install Zend_Debugger on CENTOS

In setting up a local development server, I need to enable zend_debugger on centos server.

The newer version of the debugger is renamed as Studio Web Debugger (http://www.zend.com/en/products/studio/downloads). Download the debugger and follow the instruction.

However, on CentOS there might be some additional issue:

1. if SELinux is enabled, you will get warnings like

Failed loading /usr/lib/php/modules/ZendDebugger.so: /usr/lib/php/modules/ZendDebugger.so: cannot enable executable stack as shared object requires: Permission denied.

To fix this, mark ZendDebugger as not need an executable stack.
        execstack -c /usr/lib/php/modules/ZendDebugger.so

To verify ZendDebugger.so does not need an executable stack, use the following command
        readelf -l /usr/lib/php/modules/ZendDebugger.so | grep STACK

outputs:
        GNU_STACK 0x000000 0x00000000 0x00000000 0x00000 0x00000 RW 0x4

The second to last column shows “RW” indicates that it does not need an executable stack.

If it shows “RWX/RWE”, the module does require an executable stack. In that case, an non-preferred approach is to turn off SELinux.

1. Please also make sure libssl.so.0.9.8 is on the system. If the system has been updated, the entry libssl.so.0.9.8 might be missing from /usr/lib.

To fix that make symbolic link for libssl.so.0.9.8 in /usr/lib.

Install rgdal on Mac OSX

sudo R64 CMD INSTALL --configure-args='--with-gdal-config=/Library/Frameworks/GDAL.framework/unix/bin/gdal-config --with-proj-include=/Library/Frameworks/PROJ.framework/unix/include --with-proj-lib=/Library/Frameworks/PROJ.framework/unix/lib' rgdal_0.7-5.tar.gz

Installing Maven for Flash Builder

I have been trying to get more familiar with Maven for sometime, but have not got the time to go to the details of setting it up and put it into practice with real project. Recently we had a Flex project which involves multiple modules. I think it is a good time to get a real start on Maven with Flash Builder.

The good friend of google search on Maven + Flash Builder results in some links on these. I tried to get to those that were published within the last year.

Maven is now an integrated part of the new Eclipse Indigo release, and maven can be installed with a few mouse click.

1. go to Help --> Install New Software


2. Select Indigo - http://download.eclipse.org/release/indigo on the Work with dropdown list


3. type m2e in the search box


4. check m2e - Maven Integration for Eclipse


5. 


6. click Next --> Next, on the last window, accept the terms of license agreement and click Finish.


7. The last step, Click Restart Now to apply the newly installed m2e.


8. 

VPN Failed to connect

VNP occassionally fail to connect on my mac. It seems to be a minor crash in racoon somewhere*. Manually restarting the process seems to do the trick:

mac:~ $ ps -ef | grep racoon
0 23301 1 0 0:01.01 ?? 0:01.68 /usr/sbin/racoon
501 24444 24439 0 0:00.00 ttys000 0:00.00 grep racoon

sudo kill 23301
sudo /usr/sbin/racoon

Install Mono on CentOS

In addition to Mono website, Mono is available also at http://ftp.novell.com/pub/mono/download-stable/RHEL_5/x86_64/.

First, create a repository description in /etc/yum.repos.d. Create file mono.repo with content

[Mono]
name=Mono Stack (RHEL_5)
type=rpm-md
baseurl=http://ftp.novell.com/pub/mono/download-stable/RHEL_5/
gpgcheck=1
gpgkey=http://ftp.novell.com/pub/mono/download-stable/RHEL_5/repodata/repomd.xml.key
enabled=1

Second, install the Mono “server” stack:
        yum clean all
        yum install monotools-addon-server

Wait for all packages installed. The binary file will be installed at /opt/novell/mono/bin.

To setup the running environment, run
        source /opt/novel/mono/bin/mono-addon-environment.sh

To verify everything is installed:
        mono --version

Android App Architecture

This is a set of notes that I made for my own reference.

Android application does not have a main method as desktop application have. This is because Android application is invoked by the Android system whenever any part of the application is needed, and the Android will instantiates corresponding java objects. This is made possible by components based architecture.

Android application is a collection of components (activities, services, content provider, and broadcast receivers). Not all these components need to exist at the same time in the same application. But all the components share resources, e.g. databases, file systems etc.. The components communicate with each other by intents, which are described by a manifest in application package.

What is Activity and Service?

Activities are components in Android App to presents user interface, which is similar to like WinForms in .NET desktop application. A service is similar to activity but with no user interface. A service runs in the background all the time.

replicate directory structure only

To replicate a directory structure only:

find * -type d -exec mkdir [TARGETDIR]/\{\} \;

Air for Android

Missing functions from Air SDK

• activating phone vibration
• access android native contact list
• creating android intents
• messaging to status bar
• enable one air app to open another
• creating widgets

To convert desktop air app to android

• the WindowedApplication application MXML tag needs to be changed to ViewNavigatorApplication. WindowedApplication assumes there is a NativeWindow, which is not the case on Android.
• In the Application descriptor, the namespace must be 2.6 or later and the visible tag must be set to true.

The following desktop functionalities are not supported on Android:

ActionScript 2, ContextMenu, DatagramSocket, Dockicon, EncryptedLocalStore, HTMLoader, LocalConnection, NativeMenu, NativeWindow, PrintJob, SecureSocket, ServerSocket, StorageVolumeInfo, SystemTrayIcon, Updater, XMLSignatureValidator

LiveUpdate

on my mac, the live update come up every hour. To find out what’s causing it, the following are some useful commands:

1. check current live update settings

sudo symsched -l

Module Name On UI Freq Day Time Args

--------------

---

-------- --- --- -------- ----- ------ ----

LiveUpdate DefaultLiveUpdateSchedul 1 0 Hourly 04:33 "All Products"

It is set to hourly update and not in quiet mode.

1. delete current setting

sudo symsched -d all

1. add new policy

sudo symsched LiveUpdate "LiveUpdate" 1 0 -daily 09:00 "All Products" -quiet

1. check new settings

Module Name On UI Freq Day Time Args

--------------

---

-------- --- --- -------- ----- ------ ----

LiveUpdate LiveUpdate 1 0 Daily 09:00 "All Products" -quiet

Now it is running in quiet mode.

vsftp server

1. Start vsftp automatically

If the FTP service shall be operated with inetd we open the configuration file "/etc/inetd.conf" with an editor:

# ftp stream tcp nowait root /usr/sbin/tcpd in.ftpd
ftp stream tcp nowait root /usr/sbin/tcpd vsftpd


xinetd
It is recommended to start the vsftp daemon with xinetd which is more up to date than inetd. Some updates are e.g. logging of requests, access control, binding of the service to a specific network interface and so on. A very good introduction to xinetd can be found under [7]. After the modification restart of xinetd is necessary. The configuration of xinetd could look like this:

# vsftp daemon.
service ftp
{
disable = no
socket_type = stream
wait = no
user = root
server = /usr/sbin/vsftpd
per_source = 5
instances = 200
no_access = 192.168.1.3
banner_fail = /etc/vsftpd.busy_banner
log_on_success += PID HOST DURATION
log_on_failure += HOST
nice = 10
}

Retrieve Unique Values from gisdata

import arcpy
from arcpy import env

env.workspace = "c:/data"

patch_shp = "test.shp"

field = "GRIDCODE"

valueList = []

rows = arcpy.SearchCursor(patch_shp)
for row in rows:
    valueList.append(row.getValue(field))

uniqueSet = set(valueList)
uniqueList = list(uniqueSet)
uniqueList.sort()

del rows
del row

print uniqueList

Zend Framework with IIS 7.0

Zend Framework uses Fron Controller pattern to redirect incoming request. On Apache web server, mod_rewrite can be used to redirect the request. What I am interested is how to support url rewrite in IIS 7.0.

Google search revealed there is a URL Rewrite module for IIS 7.0.

SQL Server 2008 RTM is available at MSDN

 

MSDN subscribers can get the RTM.

DBCC LOG

There is an undocumented command for checking SQL Server transaction log file for 7.0 and 2000.

To use it: DBCC log(dbname|dbid, [type=-1|0|1|2|3|4])

The meaning of type is

-1: 4 + hex dump of low row info, checkpoint begin, DB version, and Max XDESID

from 0 to 4, more information about the transaction is retrieved. Default value is 0.

How to extract msi content?

 

From windows command line tool, msi content can be extracted using msiexec command.

With C:\>msiexec, a windows installer window will come up showing the syntax of msiexec. To actually extract the content,

msiexec /a msifile /qb TARGETDIR=outfolder

SQL Injection

Microsoft published a security advisory (954462) on June 24, 2008 warning about the rising occurrence SQL Injection attack. "These SQL injection attacks do not exploit a specific software vulnerability, but instead target Web sites that do not follow secure coding practices for accessing and manipulating data stored in a relational database."

This morning, I find out that one of our databases was subjected to this issue, which causing the web site failed to launch. We have to restore the data from backup.

One useful tool, (also suggested in the security advisory) is HP Scrawl, which help web site administrators to detect SQL Injection vulnerabilities.