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Viewing Posts from December, 2007

What is a reverse proxy?

08:04 AM December 08, 2007

In the web world, a reverse proxy is often used to balance traffic going to a site across several servers. Here is a snippet from the sans institute that explains a reverse proxy in simpler terms:

So what exactly is a Reverse Proxy?

First let's review what a forward proxy or proxy is and how it works. A forward proxy acts as a gateway for a client's browser, sending HTTP requests on the client's behalf to the Internet.

The proxy protects your inside network by hiding the actual client's IP address and using its own instead.

When an outside HTTP server receives the request, it sees the requestor's address as originating from the proxy server, not from the actual client.

A Reverse Proxy proxies on behalf of the backend HTTP server, not on behalf of the outside client's request, hence the term "reverse".

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Tags: Servers, Hosting, General

First Post 11:31 AM December 07, 2007
Welcome to our blog! This purpose of this blog is to provide the public with cool information regarding networking, web design & development, ruby on rails, etc. etc. Hope you enjoy!

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Tags: General

attr_accessor and ruby object variables

08:34 AM December 21, 2007

In most other languages(java, c++, etc.), when you create an object, you have to define the variables that will make up the structure of the object. You also usually add a getter(retrieves the variable) and a setter(sets/writes the contents of the variable) so you can access the variable.

However, in Ruby, you only need one line of code that will do all of the above:

attr_accessor :myvar

This creates the getter and setter methods from the variable, which(by default) look like this:

def myvar #this is the getter

@myvar #returns the contents of @myvar

end

def myvar(anything) #this is the setter

@myvar = anything #set the contents of myvar to anything!

end

You're also looking at the code to override the methods, too! Example: If you want to create a backup variable whenever you create the original, do this:

app/model/example.rb

Class Example

attr_accessor :myvar

def myvar=(anything) #this is the setter

@myvar_backup = @myvar #backup the original variable

@myvar = anything #set the contents of myvar to anything!

end

script/console

@myExample = Example.new
=> #<Example:0x2b50b2c3d560>
>> @myExample.inspect # see what the object has
=> "#<Example:0x2b50b2c3d560>"
>> @myExample.myvar = "hello!" # set the variable
=> "hello!"
>> @myExample.inspect # see what the object has now
=> "#<Example:0x2b50b2c3d560 @myvar_backup=\"hello!\", @myvar=\"hello!\">"

Also, if you just wanted the getter or setter only, you would use:

attr_reader :myvar or attr_writer :myvar