Overview
This is another article
that talks about URL shortening services. Today we are going to talk about Cligs,
one of the popular shortening services on the web.
Be prepared!
Introduction
Today we are talking about another popular shortening service; it's
Cligs, one of the most popular
shortening services that provide lots of premium features for FREE.
Enough talking, let's begin
the discussion.
In December 2009, Cligs
acquired by Mister Wong (a very
nice bookmarking service.)
Description
How Cligs can help you?
Cligs gives you plenty of features, including the following:
- Shortening URLs (registered and non-registered
users): You get a short URL that's no more than 20 characters (Tweetburner
is 22 and
is.gd is only 18) including the domain
http://cli.gs.
- URL Management (registered users only): It allows
you to manage your short URLs, to edit them, and to remove them if you like.
- Real-time Analytics (registered users only): How
many clicked your link, and when.
- URL Previewing
(registered and non-registered users): Preview the URL before opening it.
Protects you from spam and unwanted sites.
API
Cligs provides you a very
nice API with
many advantages. The first advantage that we want to talk about is its
simplicity. The API is very simple; it has just two functions, one for
shortening URLs, and the other for expanding short URLs (to expand a
URL means to get the long URL from the short one.)
Another advantage of this
API is that it allows you to shorten the URLs whether you are a registered user
or not. Of course a registered user need to get an API key in order to link the
API calls to his accounts so he can manage the links generated by the API and to
watch the analytics.
Shortening URLs
The first function is used
for shortening URLs and it's called, create. This function has the
following address:
http://cli.gs/api/v1/cligs/create?url={1}&title={2}&key={3}&appid={4}
The API is still in version
1, that's why you see 'v1' in the address. This function takes four parameters,
only the first one is required, other parameters are used for authentication:
- Url: Required. The URL to be shortened.
- Title: Optional. For authenticated calls
only. The name that would be displayed on the short URL in your control
panel (used for managing your URLs.)
- key: Optional. If you are a registered user
and you want to link the API calls to your account, you'll need to enter
your API key here.
- Appid: Optional. If you have used an API
key, then you have to provide your application name that used to generate
this API call (help users know the source of the link.)
So how can you use this
function? If this is an anonymous call (i.e. no authentication details
provided,) just call the function providing the long URL in its single required
argument.
If you need to link this
call to a specific account, then you'll need an API key, which the user can get
by signing in to his Cligs account, choosing 'My API Keys', then clicking
'Create New API Key' (if he doesn't have one you.) The last step generates an
API key that's no exactly 32 characters (see figure 1.)
After you get the API key,
you can push it to the function along with your application name in the
appid argument.
What about the title
argument? For registered users, they can access their clig list (see
figure 2) and see the URLs they shortened and the titles they choose above each
of the URLs.
Now, let's code! The following function makes use of the Cligs API to
shorten URLs. It accepts three arguments, the long URL, the API key, and the
application name. If the API key is null (Nothing in
VB.NET,) the call is made anonymously, otherwise, the API key and the
application name are used.
// C#
string
Shorten(string
url, string
key, string
app)
{
url = Uri.EscapeUriString(url);
string
reqUri =
String.Format(@"http://cli.gs/api/v1/cligs/create?url={0}",
url);
if
(key != null)
reqUri +=
"&key="
+ key + "&appid="
+ app;
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(reqUri);
req.Timeout = 5000;
try
{
using
(System.IO.StreamReader reader =
new
System.IO.StreamReader(req.GetResponse().GetResponseStream()))
{
return
reader.ReadLine();
}
}
catch
(WebException ex)
{
return
ex.Message;
}
}
' VB.NET
Function Shorten(ByVal url As String, ByVal key As String, ByVal app As String) As String
url = Uri.EscapeUriString(url)
Dim reqUri As String = String.Format("http://cli.gs/api/v1/cligs/create?url={0}", url)
If key Is Nothing Then
reqUri &= "&key=" & key & "&appid=" & app
End If
Dim req As WebRequest = WebRequest.Create(reqUri)
req.Timeout = 5000
Try
Dim reader As System.IO.StreamReader = New System.IO.StreamReader(req.GetResponse().GetResponseStream())
Dim retValue As String = reader.ReadLine()
reader.Close()
Return retValue
Catch ex As WebException
Return ex.Message
End Try
End Function
Expanding
URLs
The other function we
have today is the expand function that's used to get the long URL
from the short one (e.g. to expand the short URL
http://cli.gs/p1hUnW to be
http://JustLikeAMagic.com.) This
function is very simple and it has the following address:
http://cli.gs/api/v1/cligs/expand?clig={1}
This function accepts
only a single argument, that's the clig (short URL) to be expanded.
The clig can be specified using one of three ways:
- The clig ID. e.g. p1hUnW.
- The raw URL. e.g.
http://cli.gs/p1hUnW.
- The encoded URL. e.g.
http%3A%2F%2Fcli.gs%2Fp1hUnW.
You can read more about URL encoding
here.
Now it's the time for
code! The following function takes a clig and returns its original URL:
// C#
HTML clipboarstring Expand(string url)
{
url = Uri.EscapeUriString(url);
string reqUri = String.Format(@"http://cli.gs/api/v1/cligs/expand?clig={0}", url);
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(reqUri);
req.Timeout = 5000;
try
{
using (System.IO.StreamReader reader =
new System.IO.StreamReader(req.GetResponse().GetResponseStream()))
{
return reader.ReadLine();
}
}
catch (WebException ex)
{
return ex.Message;
}
}
' VB.NET
Function Expand(ByVal url As String) As String
url = Uri.EscapeUriString(url)
Dim reqUri As String = String.Format("http://cli.gs/api/v1/cligs/expand?clig={0}", url)
Dim req As WebRequest = WebRequest.Create(reqUri)
req.Timeout = 5000
Try
Dim reader As System.IO.StreamReader =New System.IO.StreamReader(req.GetResponse().GetResponseStream())
Dim retValue As String = reader.ReadLine()
reader.Close()
Return retValue
Catch ex As WebException
Return ex.Message
End Try
End Function
Where to go next
Some other articles
about URL shortening services are available
here.