At this time I wrote my own craptacular mashup called The Gob Shite, this site was a mashup of Google’s YouTube, Google’s News feeds and a new API of my own called the TrendEngine. TrendEngine was developed using Google Hot Trends information and provided some level of stability to the constantly changing trend list. It does this by detecting reoccuring trends in the list and applying a weighting formula to them.

TrendEngine currently operates from a private server written in PHP, I am currently converting this code to Java to run on Google’s App Engine. The new TrendEngine service will be publicly released shortly and will be listed up on ProgrammableWeb for all to use.

More information to come soon.

Error Domain=NSCocoaErrorDomain "no valid 'aps-environment' entitlement string found for application"

If after you have verified your Provisioning Profile and application settings you still get the error, try the following:

Go to the Project Settings in the Project Menu

Select the exact Code Signing identity for your application rather then the automatic selection.

The following code is simple (but as a newcomer to Obj-C took me ages to put together). Just press the View Source button on the following panel to see all the code (I am having trouble getting code wrapping to work, so this will be the case until I find a decent syntax highlighter plugin).

- (void)application:(UIApplication *)app didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken {

	NSLog(@"devToken=%@",deviceToken);

	NSString *host = @"yourhost";
	NSString *URLString = @"/register.php?id=";
	URLString = [URLString stringByAppendingString:id];
	URLString = [URLString stringByAppendingString:@"&devicetoken="];

	NSString *dt = [[deviceToken description] stringByTrimmingCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@"<>"]];
	dt = [dt stringByReplacingOccurrencesOfString:@" " withString:@""];

	URLString = [URLString stringByAppendingString:dt];
	URLString = [URLString stringByAppendingString:@"&devicename="];
	URLString = [URLString stringByAppendingString:[[UIDevice alloc] name]];

	NSURL *url = [[NSURL alloc] initWithScheme:@"http" host:host path:URLString];
	NSLog(@"FullURL=%@", url);

	NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];

	NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
}

If you spot the above code and think “why the hell has he done it like that”, it is because I don’t know any better at the moment. If there is a better way please leave some constructive feedback via the comment form.

My first app will be for a Nagios Pager service that will utilise the Push Notification features just released in iPhone OS 3.0. There will be two versions, Nagios Pager and Nagios Pager Pro. Nagios Pager will be a stand alone application that will talk to a backend service for delivering Push Notifications for Nagios alerts, Nagios Pager Pro will contain all the features of Nagios Pager as well as an iPhone based Nagios client.

The standard version will be released in the App Store for free and the Pro version will be for a small cost. There will also be various access methods for the backend service required for the Apple Push Notification Service (APNS). A free subscription to the backend will allow for one phone to access one nagios backend, while a paid subscription will allow for multiple phones access to multiple backends.

If you are interested in this service or you are interested in entering the beta program let me know via a comment and I will get in contact with you. Stay tuned for more development news.

There wasn’t much clear documentation out there on exactly what I wanted to do so I ended up using a couple of code examples I found in the end (links provided below for original source) and modifying them for my needs.

The end result is extremely simple to understand (however the information was not easy to find) so I thought I would post the details here in hopes that someone else wanting to do the same thing ends up finding this article rather than searching for hours and not finding exactly what is required. (As an a-side, most of what I found online was regarding using premade XML files, and the generation of XML files and not generating and sending the XML request on the fly). Also I wasted a bit of time because of my lack of knowledge on how various Streams work together, but that is another issue entirely.

The following is code for C# but should apply to other .NET based languages (with an appropriate change of syntax).

Required Namespace Imports

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.IO;
using System.Net;
using System.Threading;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml;

Code

WebRequest req = WebRequest.Create("http://URLHERE/WebService");
req.Method = "POST";
req.ContentType = "text/xml";
Stream requestStream = req.GetRequestStream();

XmlTextWriter xml = new XmlTextWriter(requestStream, null);

xml.WriteStartDocument();

// The DocType will be different for most situations, this
// is what works for me.
xml.WriteDocType("Request", null, "somefile.dtd", null);
xml.WriteStartElement("Request");
xml.WriteStartElement("InfoRequest");

// These values could come from any source
xml.WriteElementString("Username", "<>");
xml.WriteElementString("Password", "<
>");
xml.WriteElementString("Info", "something");
xml.WriteEndElement();
xml.WriteEndElement();

// When Close() is called the request is sent to the server
xml.Close();

// Use a WebResponse Component to retrieve the response
WebResponse rsp = req.GetResponse();
XmlTextReader xmlin = new XmlTextReader(rsp.GetResponseStream());

while (xmlin.Read())
{
  if (xmlin.NodeType == XmlNodeType.Element)
  {
    if (xmlin.Name == "Info")
    {
      String info = xmlin.ReadString();

      // Do something with returned data

    }
  }
}

xmlin.Close();
rsp.Close();

There are plenty of useful tutorials out there based on XmlTextReader and XmlTextWriter that can explain how to use them to read and write XML. So I wont cover that here. My biggest problem was finding out how to generate the XML and send it straight to the server without having to save to a file.

References:

• http://www.aspsms.com/examples/c/
• http://www.codeproject.com/KB/dotnet/XmlPost.aspx