In this post I will demonstrate using ElasticSearch to spatially query records and filter them by attributes.

ElasticSearch is built on top of Lucence which in version 4.0 supports Spatial query features, for those interested here is an example and link to javadocs.

You will need to install ElasticSearch, read about installing it here, also install marvel plugin for configuration and testing.

For this demonstration I have used data from Geofabrik. I have used point.shp file from Great Britan but you can use data from any other country as well.

I generally have been using loading gifs in my work most of the time to inform the user that the resources are being fetched asynchronously from the server.

Ajaxload website is perhaps one of the most used site to download a suitable gif.

In this post I will demonstrate a css3 only way to create a nice loading simulation

Basic Code #

We will use nested divs to create the loading animation control ```

IIS7 is quite modular, it is shipped with lots of goodies as separate modules and together it is now one of the most powerful and flexible web server.

In this post I intent to cover how we can easily configure ARR and URL Rewrite Module to get a similar functionality as of Mod Proxy in Apache.

Here I will demonstrate configuration of a reverse proxy which according to the definition is

Reverse proxy is a type of proxy server that retrieves resources on behalf of a client from one or more servers. A general use case to configure such proxies could be to handle cross domain Ajax requests, so basically if I would like to call a service hosted as http://anotherdomain.com/service from http://localdomain/service I would need to configure a proxy which will request resources from anotherdomain.com/service on behalf of localdomain ### Configuration

Raphael.JS is a SVG/VML library which helps you to create quick vector shapes and images. Its very small and compact (only 86kb),easy to use,well documented and works in all browsers and yes even IE. Here is a list of all major browsers this library works on: Chrome 5.0+ Firefox 3.0+, Safari 3.0+, Opera 9.5+ and Internet Explorer 6.0+

,finally its distributed under MIT license. In this tutorial ,I intend to introduce basics of this library and help you get started.

Generally, when I am in a middle of prototyping a concept or in a need of quickly executing Ajax requests or using browser features which would need the page to be hosted on a web server, I use Python’s SimpleHTTPServer module.

Python’s SimpleHTTPServer is a great way of serve the contents of the current directory,all one needs to do is change directory and execute a command which will expose all contents as if they were hosted in a web page.

I love JavaScript and code a lot in it .Since I code, I also encounter problems and bugs from time to time and therefore need a Debugger and a debug mechanism to view whats going on.

In good old days when I learned this language, I used JavaScript’s inbuilt alert mechanism to view the value of a variable or a property of an object. This was a terrible mechanism, calling alert was blocking, one had to press OK to continue and if you had to take a look inside an array then well it was emotionally an overwhelming task is all I would say here.

When I first started web programming, creating a center aligned div was one of the most common task that I saw myself doing.

since div is a block element, i.e. it takes up the full width available, and has a line break before and after it, it can easily be centered using relative styling

{
margin-left:auto;
margin-right:auto;
width:70%;
background-color:#b0e0e6;
}

However lately I have preferred using absolute positioning technique over relative, this works for all browsers and is best for login screens or alert messages over a translucent shim.

In this post,I am going to write about OpenShift, which is Red hat’s free, auto-scaling Platform as a Service (PaaS) for applications.

OpenShift to me is very similar to Google’s app engine in some ways,but openshift’s offerings are quite diverse, for instance support for ruby, php, Perl, node.js, etc..

Openshift is not like a traditional VPS hosting , although once registered with them, user does get a shell access,but its quite limited , instead OpenShift has a concept of gears and cartridges.

HTTP Compression is a very simple and effective way to save bandwidth and improve web applications performance over network.

Output compression is basically a process of compressing web servers response by using a loss-less compression algorithm called gzip.

This technique is fairly modern and almost all modern browsers honor it, however if a page is requested from a browser which does not send a header Accept-Encoding: gzip,deflate then the response comes back uncompressed.

Web.py has been one of my favorite web frameworks as its pretty easy to get cracking on it.

It’s super quick to install and one can come up with a prototype and rapid web services in matter of minutes.

Install on windows #

If you haven’t configured easy_install on windows, then read this article.

Once easy_install has been configured believe it or not, all you have to do is open a command prompt and type

If one has been using python, then installing various libraries and modules is basically a breeze using easy_install utility, however for folks using windows, easy_install utility has to be setup properly before using it.

First lets make sure that python is properly installed and PYTHON_HOME environment variable is configured:

Install Python on Windows #

If not already installed download python installer from here.

After it’s done downloading, double click to run the installer, and select default options (unless you have other custom needs of course ).

I had been hosting this blog in the past for an extremely competitive (read cheap) price here at Arvixe . I was using ASP.net based blogging software called BlogEngine. over and all I will describe my experience as pleasant. Arvixe is a great Hosting Provider, has good up time and has plans which are easy on the pocket, and does almost all the common stuff like emails and cpanel ,blah blah that other hosting provider do, but kinda does it on a low price. I was a happy blogger for an year although I could only manage close to 8 post and and few demos in that time.

Few days ago I was experimenting with a nifty technique of embedding images in web pages by base64 encoding them first and then using a standard known as Data URI Scheme, which basically defines a method of assigning a ‘src’ of an image tag as a base64 serialized string, like this:

background-image: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABkAAAAUBAMAAACKWYuOAAAAMFBMVEX///92dnZ2dnZ2dnZ2dnZ2dnZ2dnZ2dnZ2dnZ2dnZ2dnZ2dnZ2dnZ2dnZ2dnZ2dnYvD4PNAAAAD3RSTlMAACTkfhvbh3iEewTtxBIFliR3AAAAUklEQVQY02NgIBMwijgKCgrAef5fkHnz/y9E4kn+/4XEE6z/34jEE///A4knev7zAwQv7L8RQk40/7MiggeUQpjJff+zIpINykbIbhFSROIRDQAWUhW2oXLWAQAAAABJRU5ErkJggg==");

   

Although this technique could save some server round trips, however Microsoft ver. (IE < 8). does not support this scheme even though its a standard, which then makes this technique unfavorable to use as its not cross browser.