Stuff I'm working on at the moment

Posts in category Archive Post

WP error,copying XML children,ztdummy fun and ArrayDeleteAt gotcha

Mar24
2009 Leave a Comment Written by edlong

Hi,
I haven’t posted in a while as my site got blocked by IT at work for some reason!

I’ve had a lot of stuff recently that I could have posted it but unfortunately I’ve forgotten most of it so don’t have a massive amount to write about.

Firstly I had a problem with my wordpress account that when someone attempted to subscribe to the blog I would get an error something like

 “Cannot modify header information - headers already sent”

After having a look around the place I saw that this is resolved but having extra whitespace before or after tags. I had some JS in one of my php that was causing the RSS subscription to crap out. Fixed it so should be working now.

Got my MSc result in the last couple of days, got 95% in my thesis which can be got here. That means I got a ‘Distinction’ in my MSc which I’m very happy about. You can read about my progress through the GOAP archives in the blog.

I got an error when using ColdFusion’s XMLParse to go through two XML documents and copy one part of the XML to another document. I was getting the error ‘WRONG_DOCUMENT_ERR’ when attempting to do an ArrayAppend to an existing XML node. So I had to go and create each node individually using recursion. Here’s a snippet of the code, I had to create each node individually and set the attributes, Cdata etc.

WARNING: I’ve modified this from my original code and not tested fully so mightn’t work but is v close to working only needs a few small changes to work I’d imagine.

I was having a problem with Asterisk on a VM Ubuntu server during the week. The error message I was getting was ‘app_meetme.c: Unable to open pseudo device’. The reason for this error is that MeetMe requires a timing device to work, there is Zaptel hardware for Asterisk that you can buy and use. On the Asterisk CLI type zap show status, if you don’t have anything there then thats you’re problem. A module called Ztdummy can emulate the Zaptel hardware and allow the Meetme app to work. To do this I got the Zaptel source from SVN svn co http://svn.digium.com/svn/zaptel/branches/1.4 . , did a ./configure, make and make install and make config. After that I ran this script to finish the install.

genzaptelconf -sdvM
/etc/init.d/zaptel start

Finally for now I had another issue when deleting items from a ColdFusion array. I was looping through one by one and on a certain condition delete an element and move on. I ended up getting the error:

Cannot insert/delete at position 9.
    The array passed has 8 indexes. Valid positions are from 1 to 8.

Coldfusion reorders the indexes after deleting and isn’t too clever about it so for some reason seems to think that there is 9 elements in the array when 1 has been deleted. The solution is very simple(although I think the language should be a little clever to handle this properly):

Posted in Asterisk, ColdFusion, XML

New iTouch apps, PSP firmware and creating a tar.gz archive

Mar24
2009 Leave a Comment Written by edlong

Hi again,

I’ve been fishing around for new iTouch apps and have found some excellent new ones out there. Check out Simplify Media, its brilliant allows you to connect to your iTunes library as long as you have a Wifi connection. Just install the app on your Mac or PC, create an account and download the Simplify Media app from the iTouch Installer and log in there too. Takes a little while to get the libraries the first time but after that its very fast. The songs then buffer as if you were streaming them, I’m very impressed with the speed of it – a must have for any iTouch/iPhone owner.

Another site that has lots of recommendations but isn’t quite working for me yet is Seeqpod which is basically a search engine that searches for music in Safari and apparently can stream the audio over the net. The audio doesn’t start for me yet, not sure why. There does seem to be a HUGE amount of music there though.

iPhysics is very very cool ‘game’, you can draw lines, objects and then the physics engine takes over and the new objects bounce around under gravity and as you would expect under Newtonian phyiscs. The really impressive thing is that it is dynamic, you can create objects on the fly and they’ll interact with one another and bounce around the place, fun. The game part involves moving a ball across a level to a small red box, there’s tons of user-created levels so its quite fun from what I’ve played of it. Here’s a video of something similar I found a few weeks ago, thought it was only a college experiment though :)

Similar to the SimplifyMedia is the telekinesis project. It looks really cool and I’ve not had a chance to test this yet but will give it a goo this evening and see how it works.

Also ScummVM is available for the iTouch now which means that……….yes Monkey Island my all-time favourite game can be played on it. Also can play all the ScummVM developed games, Sam & Max, Indy series and all the other classic adventure games. Hurray!

MobileCast is an other app that can be installed via the Installer. It allows you to fetch podcasts from RSS feeds without having to sync up with iTunes, this wil be handy when I’m travelling and can just pick up random Wifi hotspots.

I’ve recently upgraded the firmware on my PSP to version 3.90 M33-3, mainly because I want to play Pro Evo 2008. Check out Dark Alex’s site with all the releases there, I upgraded from version 3.51. Always pretty nervous when doing it but he hasn’t let me down yet.

Linky to his site

Finally here’s how to quickly create a tar gz archive. Here it is

  tar -pczf nameOfArchive.tar.gz /directoryToZip
Posted in iTouch, Linux, Mac

Flex Dragging, determining cursor position with Javascript and XMLParsing with ColdFusion!

Mar24
2009 Leave a Comment Written by edlong

Hi all,

I’ve recently been programming a way of Flex talking to a regular web-page using FAB – Flex Ajax Bridge. I basically had a TileList of images and wanted to be able to drag an image from the Flex app onto a text-box and the text box would become populated with the url of the image. Sounds tricky? Well it was.

First the main thing I had to do was to get the correct Javascript files included at the top of the HTML page….

Those files can be got from the Adobe FAB page I got the other by Googling for it.

To get Flex working with FAB you need to reference the bridge directory that must also be available to the swf so below the tags I put in this:

So thats all thats needed for Flex to talk to Javascript! Well almost, more will come on that…..

Firstly the code to perform dragging within Flex.


	
        	import mx.containers.Canvas;
        	import model.AssetModel;
            import mx.managers.DragManager;
            import mx.core.DragSource;
            import mx.events.DragEvent;
			import control.AssetController;

			import com.adobe.cairngorm.control.CairngormEventDispatcher;
			import com.adobe.cairngorm.control.CairngormEvent;

            private var myModel:AssetModel = model.AssetModel.getInstance()			

			private function onClick():void{
				this.dispatchClickEvent();
			}  

            private function dragAsset(event:MouseEvent, img1:Image,
                format:String):void {
                var dragInitiator:Image=Image(event.currentTarget);
                var ds:DragSource = new DragSource();
                ds.addData(img1, format);               

                var imageProxy:Image = new Image();
                imageProxy.source = data.url;
                imageProxy.height= this.height;
                imageProxy.width= this.width;

                DragManager.doDrag(dragInitiator, ds, event,
                    imageProxy, 0, 0, 0.75);
                myModel.dragging = true;
            }                 

            private function dispatchClickEvent():void
            {	var assetEvt : CairngormEvent = new CairngormEvent(AssetController.SELECT_QUESTION_ASSET_EVENT);
				assetEvt.data = data;
				CairngormEventDispatcher.getInstance().dispatchEvent(assetEvt);
            }

             private function quitDrag():void
            {
            	myModel.dragging = false;
            }

So this image is an itemRenderer within a TileList using a dataProvider so each ‘item’ has a url associated with it from the dataProvider. myModel is a central Cairngorm location for storing objects that are used often or accessed in many places in the flex application. So I have a dragging variable that is true if the image is being dragged, false if the dragging is completed.

Within my main MXML I had a function:

public function getDraggedImageURL():String
{	var draggedItem:String = "";
	if(myModel.selectedAsset.url != null && myModel.dragging == true)
	{
		draggedItem = "" + myModel.selectedAsset.url;
	}

        return draggedItem;
}

So when this is called we check if there is currently dragging taking place(dragging var) and then make sure we’ve actually an asset selected in the TileList(another var in the model that is set when you click on the image,see earlier image definition)

So not within the HTML file I created a textarea with a javascript function called when the mouseup event is called(i.e. when you let go of the mouse button and are over the text area, this is triggered when dragging from a flex app to the text-area)

So the doSomething function is quite simple:

function doSomething()
{
	flexApp = FABridge.flash.root();
	var selectedImage = flexApp.getDraggedImageURL();
	if (selectedImage != "") {
		var text1 = document.getElementById("text1");
		text1.value += selectedImage;
	}

}

The first line creates a bridge or connection with the flex app. Next we execute the getDraggedImageURL that is defined above. If the string returned isn’t empty then we know we have an image url and it appends this onto the existing text in the textarea. This also stops insertion occuring when the user clicks on the text area without dragging from the flex app.

Note: It appears from testing that FAB doesn’t work with Safari 3.0, I can’t test it with any of the earlier Safari versions as they won’t work on Leopard!

I’ve used Javascript to detect the current position of the cursor in a text area. This is used to insert the image url when you’re editing a text-box. Here is the code

function storeCursorPosition(text1)
{
	if (document.selection)
	{

		sel = document.selection.createRange();

		cursorPos = sel.select();
	}

       //MOZILLA/NETSCAPE support
	else if (text1.selectionStart || text1.selectionStart == '0')
	{
		var startPos = text1.selectionStart;

		cursorPos = startPos;

	}

	//Anyone else.
	else
	{
		cursorPos = text1.value.length;
	}
}

CursorPos stores the cursor position globally and then is used to break up the text-areas value into two, insert the new string in the middle and put the two broken pieces of the string back and setting the text-areas value again.

Here is the html code to store the cursor position.

I’ve tested this in Firefox and Safari and it works A-OK!

Not tried either in IE yet either….

Was playing with XMLParse with ColdFusion, its really cool was sick of getting external XML parsers for other languages like PHP but its v v easy with ColdFusion. Yippee

Posted in ColdFusion, XML

Crazy dragging with Flex, setting DragManager styles

Mar24
2009 4 Comments Written by edlong

Yesterday I was working with Flex again and made a drag and drop application that contained a tile list of images that can be dragged into a text-area which then becomes populated with the url of the image. The problem I was having was that when I dragged in a TileList in Flex off the TileList the scroller went crazy and flew either up or down depending on which way I was dragging the image. The solution I found to this problem was to disable the TileList whenever I clicked on the image. It was actually very very simple, after asking Mark of course.

I had a variable in my Cairngorm model called dragging which is true if we’re dragging an image and false if not. I just bound this dragging boolean to the enabled attribute of the TileList. So it became:

This fixed the TileList going crazy whenever dragging and scrolling up or down really fast as the TileList just disabled itself(greyed out the scroller bar on the right) whenever a dragging operation is performed.

I was also getting a nasty looking cursor when dragging across the tilelist, it had a red circle with a white X within it. I didn’t want that so I just overwrote the default CSS style

DragManager
{	rejectCursor: Embed(source="assets/copyCursor.png");
}

I included the main style within the Application

I was playing around with Voxy today, its an open source VoiceXML plugin for Asterisk. Problem with it is that it doesn’t include ANY TTS or audio playback so if you have a VoiceXML document it will go off and parse it fine but do nothing with it! So its pretty useless as it stands as to alter it you have to go and mess around with the C source and recompile which isn’t too appealing. The mayhem of VoiceXML and Asterisk goes on. Will try VXIAsterisk again tomorrow(don’t have much hope though given their pathetic record in the past every time I’ve tried to compile/install it for use alongside Asterisk)

Posted in Flex

ODBC Cdr with Asterisk

Mar24
2009 Leave a Comment Written by edlong

Hi all,
Today I’ve been setting up Asterisk to work with ODBC and MySQL.

I started out by creating the MySQL table, the code is:

CREATE TABLE cdr(calldate DATETIME NOT NULL,clid varchar(80) NOT NULL DEFAULT 'aDefaultValue',src varchar(80) NOT NULL DEFAULT 'aDefaultValue',dst VARCHAR(80) NOT NULL DEFAULT 'aDefaultValue',dcontext VARCHAR(80) NOT NULL DEFAULT  'aDefaultValue',channel VARCHAR(80) NOT NULL DEFAULT  'aDefaultValue',dstchannel VARCHAR(80) NOT NULL DEFAULT 'aDefaultValue',lastapp VARCHAR(80) NOT NULL DEFAULT  'aDefaultValue',lastdata VARCHAR(80) NOT NULL DEFAULT  'aDefaultValue',duration int(11) NOT NULL DEFAULT '0',billsec int(11) NOT NULL DEFAULT '0',disposition VARCHAR(45) NOT NULL DEFAULT  'aDefaultValue',amaflags int(11) NOT NULL DEFAULT '0',accountcode VARCHAR(20) NOT NULL DEFAULT  'aDefaultValue',uniqueid VARCHAR(32) NOT NULL DEFAULT  'aDefaultValue',userfield VARCHAR(255) NOT NULL DEFAULT 'aDefaultValue');

WARNING: I’ve found that any spaces in the above create table code will cause syntax errors in mySQL.

I did the install in Ubuntu so you may need to do other steps to install the drivers needed for ODBC on your OS.
You need to get MySQL and iODBC and unixodbc.

apt-get install unixodbc libmyodbc unixodbc iodbc

This should install all the packages needed for MySQL and ODBC.

Go and edit your /etc/odbcinst.ini and paste in:

[MySQL]
Description     = MySQL ODBC MyODBC Driver
Driver          = /usr/lib/odbc/libmyodbc.so
Setup           = /usr/lib/odbc/libodbcmyS.so
CPTimeout       = 0
CPReuse         = 0

Now go and edit /etc/odbc.ini

[MySQL-asterisk]
Description     = MYSQL ODBC Driver Testing
Driver          = MySQL
Socket          = /var/run/mysqld/mysqld.sock
Server          = localhost
User            = YourUsername
Password        = YourPassword
Database        = YourDatabase
Option          = 3

No go and edit /etc/asterisk/cdr.conf and set enabled = yes and at the bottom of the cdr.conf add the following

[odbc]
usegmtime=yes
loguniqueid=yes
loguserfiled=yes

Then go and edit /etc/asterisk/res_odbc.conf, add this:

[mysql]
enabled => yes
dsn => MySQL-asterisk
username => YourUsername
password => YourPassword
pre-connect => yes

Finally edit /etc/asterisk/cdr.conf and replace the existing global with:

[global]
dsn=MySQL-asterisk
;username=asterisk
;password=asterisk
loguniqueid=yes
dispositionstring=yes
table=cdr               ;"cdr" is default table name
usegmtime=no

Go to your asterisk console ( type asterisk -vvvvvvvvr) and type restart now
Connect once more and type module reload res_odbc. Make sure it all looks good
Type module reload cdr_odbc and see if it is connecting ok.

If it doesn’t make sure you can access mysql from the command line and make sure you have given asterisk permissions on the mysql database. i did this but it may be a bit insecure, I’m only developing at the moment

GRANT ALL PRIVILEGES ON asterisk.* TO YourUsername@localhost IDENTIFIED BY 'YourPassword'
Posted in Asterisk

Installing and customising App Conference Vicidial

Mar24
2009 2 Comments Written by edlong

After getting App_conference working recently but after using it for a bit I found that it is a little TOO stripped down for my liking. It doesn’t do anything else besides put people into a conference. This may be fine for some people but I need more than that so I decided to check out the Vicidial version of app_conference that sends DTMFs to the Vicidial Manager. It also plays enter and exit sounds which I thought would be nice to have. I thought that if I could see what was receiving the DTMFs and sending them off to the Vicidial manager I could modify this and perform custom actions.

Well after getting the code for app_conference here and first attempted to compile it I got a few errors. I’m compiling on a Ubuntu Server with Asterisk already installed, see my previous post about what the pre-requisites are for app_conference. Some of the errors are below:

app_conference.c:51: warning: data definition has no type or storage class
app_conference.c:51: warning: type defaults to ‘int’ in declaration of ‘STANDARD_HANGUP_LOCALUSERS’
app_conference.c:52: warning: data definition has no type or storage class
app_conference.c:52: warning: type defaults to ‘int’ in declaration of ‘LOCAL_USER_DECL’
app_conference.c:55: warning: no previous prototype for ‘unload_module’
app_conference.c: In function ‘unload_module’:
app_conference.c:58: warning: passing argument 1 of ‘__ast_module_user_hangup_all’ from incompatible pointer type
app_conference.c: At top level:
app_conference.c:67: warning: no previous prototype for ‘load_module’
app_conference.c:80: warning: no previous prototype for ‘description’
app_conference.c:85: warning: no previous prototype for ‘usecount’
app_conference.c: In function ‘usecount’:
app_conference.c:87: warning: implicit declaration of function ‘STANDARD_USECOUNT’
app_conference.c: At top level:
app_conference.c:92: warning: no previous prototype for ‘key’
app_conference.c: In function ‘app_conference_main’:
app_conference.c:106: warning: implicit declaration of function ‘LOCAL_USER_ADD’
app_conference.c:112: warning: implicit declaration of function ‘LOCAL_USER_REMOVE’
app_conference.c:106: warning: ‘u’ is used uninitialized in this function
app_conference.c: In function ‘usecount’:
app_conference.c:87: warning: ‘res’ is used uninitialized in this function

Quite a few errors. After some Google’ing around I found that a lot of these errors were because the newer version of Asterisk no longer supported these variables/functions. I began to churn through the errors by going into app_conference.c, fixing them and recompiling.

Below are the steps I took to get the app_conference going

Replace ‘STANDARD_HANGUP_LOCALUSERS’ with
ast_module_user_hangup_all(); // defined in asterisk/module.h

struct localuser *u ; with
struct ast_module_user *u ;

LOCAL_USER_ADD( u ) ; with
u = ast_module_user_add(chan);

LOCAL_USER_REMOVE( u ) ; with
ast_module_user_remove(u);

place static before the ‘int’ & char for all methods with it except for app_conference main function.

Paste into the very bottom of app_conference main. This registers the Conference as an Asterisk module.

#define AST_MODULE “Conference”
AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY,
“Channel Independent Conference Application”);
#undef AST_MODULE

I’ve attached the new app_conference.c that I know definitely compiles to this post. After doing ‘make’ on the app_conference there are still a few warnings but they don’t matter. You’ll be left with app_conference.so. Copy this to /usr/lib/asterisk/modules. When you try to connect to the Asterisk CLI it will automatically shutdown as it spots a shared object that it previously didn’t have so you’re better off just doing /etc/init.d/asterisk restart and then joining the Asterisk CLI. Test if the module is present by typing show modules like conference and you should see it returned. If not something is wrong, you may need to add it in modules.conf so that its loaded at load time. Check out the Asterisk wiki for the Conference commands and how to run it – the version we’ve installed is down under the ‘app conference with VICIDIAL ‘ section but works well so far.

There is code in the process_incoming function in member.c that can be modified to allow dtmf actions. See the default below:

[code lang="c"]
if (
f->frametype == AST_FRAME_DTMF
&& member->send_dtmf
)
{ // send the DTMF event to the MGR interface..
manager_event(
EVENT_FLAG_CALL,
"ConferenceDTMF",
"Channel: %s\r\n"
"Key: %c\r\n",
member->channel_name,
f->subclass
) ;
[/code]

The default is to pass on the DTMF to the Vicidial manager but I’ve removed this and added in a menu system and allow the user quit out of the conference and will be adding some more features. The f->subclass contains the current DTMF pressed.

I’ve found one problem with this app at present. When audio is being played and we attempt to play another piece of audio on the same channel I get a whole bunch of repeated errors:

[Mar 10 06:47:17] WARNING[9898]: codec_gsm.c:144 gsmtolin_framein: Invalid GSM data (1)
[Mar 10 06:47:17] WARNING[9898]: translate.c:199 framein: gsmtolin did not update samples 0

This is caused as the app isn’t clever enough to realise that audio is already playing so just need to put a check in the play_basic_sound function but haven’t got round to doing this yet.

Posted in Asterisk

MD5 hex generation and recursion in ColdFusion

Mar24
2009 Leave a Comment Written by edlong

Hi there,
Today I worked on a little bit of ColdFusion that takes in a file url and generates a hex MD5 hash code from it. I used the code posted by Mark Lynch previously here.

The hex code is contained in the checksumhex variable.

I’ve been doing some recursion in ColdFusion in a CFC lately its not pretty but finally got it working.


       

       
            
                  
                            <#key#>
                   
                   
                    
                            
                   
            
                    
                           #testExample[key]#

The problem I was having was that the second key(i.e. the one in the second cfoutput, ) was having weird output, it was outputing values from a function that should previously have been entered and left again. The issue was that after going through the inner function the key value would stay from the other function. So the answer was to actually declare a key at the top of the function and use that within the cfloop. This gave me correct values at the end of the recursion.


       
        

       
              
              
                  
                            <#newItem#>
                   
                   
                    
                            
                   
            
                    
                           #testExample[newItem]#

This works, hurray!

Posted in ColdFusion

Setting up a 404 page on Hostgator

Mar24
2009 Leave a Comment Written by edlong

Hi,

Recently I’ve been looking at the recent visitor stats for my site and saw that there were a few 404s, probably from moved assets or something but the default 404 for Hostgator (my hosting company) is an ugly looking page. I wanted to change this so went into the cpanel backend and went to the “Error Pages” page to setup a 404. However this doesn’t actually work. After some looking around I found that it is fairly simple to setup myself. I just need to add the line to the .htaccess on my www webroot. The .htaccess file is extremely useful as you can setup other error pages using the same technique. The format is as follows

ErrorDocument ErrorNumber /ErrorPage

So to setup a 404 I entered the line below into my .htaccess file

ErrorDocument 404 /404.php

Setting up custom 404s is useful as you can just provide a graceful error and provide something useful back to a user(including your own headers, footers and styling) rather than an ugly server/hosting supplied page.

Possible error types that can be setup as listed below.

401 – Authorization Required
400 – Bad request
403 – Forbidden
500 – Internal Server Error
404 – Wrong page

HTAccess can also be used to deny certain ip addresses:

deny from 000.000.000.000

Finally the HTAcess file can be used to perform redirects:

Redirect /FromPage.php /ToPage.php

Front Row tomfoolery

Mar24
2009 Leave a Comment Written by edlong

Hi again,

Front Row is setup by default to point at your ‘Movies’ folder on the Mac. However I have lots of movies located in other locations on both my Mac and on extra hard-drives that I want to be able to use through Front Row(i.e. use the remote control in bed). Front Row doesn’t support the addition of new folders by default but a very easy hack gets around this. In your movies folder just create a new alias to point another folder(very easy to do just select file and create new alias) and follow this alias in Front Row and it will bring you to the required folder. Easy!

Edit: In looking this up again I’ve found this new hint which will allow volumes(and hence anything on your own Mac and external drives be available) to be added to the movies folder. I haven’t tried it yet but might do soon, sounds like a bit too much navigating to me. http://www.macosxhints.com/article.php?story=20060815123339582

Posted in Mac

PHP AGI Hangup

Mar24
2009 2 Comments Written by edlong

Hi all,

Hangups are handled by PHP AGI by registering a sig_handler function. Whenever a user hangs up then this function is called. However as I found out recently you cannot use the agi within the hangup handler. You can use the verbose command and see what it outputs to the system/error log as the verbose command outputs to the default php error log as well as to the Asterisk CLI. Here is some simple code to register your hangup handler:

function sig_handler($signo)
{	//Do some stuff in here
	exit(0);
}

//Register the hangup handler
if (function_exists('pcntl_signal'))
{
      pcntl_signal(SIGHUP,  "sig_handler");
}

I’ve no idea what pcntl_signal is but its installed alongside Asterisk by default I believe so you shouldn’t need to do anything extra to get it working.

If you are stuck, the approach we took is to set some variables in the dialplan and have some conditional statements within the dialplan to check these variables. There is a special extension ‘h’ which is called when a hangup occurs. The conditional Gotoif checks for a boolean statement which if true will attempt to go to the first extension, if false it will go to the second extension.

exten => h,1,GotoIf($[${EXISTS(${aVar})}]?2:4)
exten => h,2,DoSomething()
exten => h,3,GotoIf(${aVar} > 0 ? 4:5)
exten => h,4,Goto(some_extension)
exten => h,5,Goto(some_extension)

PS. I’ve noted that labels don’t appear to be working(for me at least) in the dialplan. By labels I mean:

exten => h(myLabel),2,DoSomething()

According to the docs I should be able either of below within a GotoIf:

exten => h,1,GotoIf($[${EXISTS(${aVar})}]?myLabel:4)
exten => h,1,GotoIf($[${EXISTS(${aVar})}]?2(myLabel):4)

Both of these fail for me, telling me that the extension doesn’t exist.

Posted in Asterisk, PHP, PHP AGI
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