From 9fd91c0b6e719cd5d2cf4d85ab0f3c94ccf492a8 Mon Sep 17 00:00:00 2001 From: admin Date: Mon, 9 Oct 2006 03:30:36 +0000 Subject: --- user_guide/libraries/table.html | 251 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 251 insertions(+) create mode 100644 user_guide/libraries/table.html (limited to 'user_guide') diff --git a/user_guide/libraries/table.html b/user_guide/libraries/table.html new file mode 100644 index 000000000..68b31165b --- /dev/null +++ b/user_guide/libraries/table.html @@ -0,0 +1,251 @@ + + + + +Code Igniter User Guide + + + + + + + + + + + + + + + + + + + + + + +
+ + + + + +

Code Igniter User Guide Version 1.5.0b1

+
+ + + + + + + + + +
+ + +
+ + + +
+ + +

Trackback Class

+ +

The Trackback Class provides functions that enable you to send and receive Trackback data.

+ + +

If you are not familiar with Trackbacks you'll find more information here.

+ +

Initializing the Class

+ +

Like most other classes in Code Igniter, the Trackback class is initialized in your controller using the $this->load->library function:

+ +$this->load->library('trackback'); +

Once loaded, the Trackback library object will be available using: $this->trackback

+ + +

Sending Trackbacks

+ +

A Trackback can be sent from any of your controller functions using code similar to this example: + +$this->load->library('trackback');
+
+$tb_data = array(
+                'ping_url'  => 'http://some-site.com/trackback/456',
+                'url'       => 'http://www.my-site.com/blog/entry/123',
+                'title'     => 'The Title of My Entry',
+                'excerpt'   => 'The entry content.',
+                'blog_name' => 'My Blog Name',
+                'charset'   => 'utf-8'
+                );
+
+if ( ! $this->trackback->send($tb_data))
+{
+     echo $this->trackback->display_errors();
+}
+else
+{
+     echo 'Trackback was sent!';
+} + +

Description of array data:

+ + + +

The Trackback sending function returns TRUE/FALSE (boolean) on success or failure. If it fails, you can retrieve the error message using:

+ +$this->trackback->display_errors(); + + +

Receiving Trackbacks

+ +

Before you can receive Trackbacks you must create a weblog. If you don't have a blog yet there's no point in continuing.

+ +

Receiving Trackbacks is a little more complex than sending them, only because you will need a database table in which to store them, +and you will need to validate the incoming trackback data. You are encouraged to implement a thorough validation process to +guard against spam and duplicate data. You may also want to limit the number of Trackbacks you allow from a particular IP within +a given span of time to further curtail spam. The process of receiving a Trackback is quite simple; +the validation is what takes most of the effort.

+ +

Your Ping URL

+ +

In order to accept Trackbacks you must display a Trackback URL next to each one of your weblog entries. This will be the URL +that people will use to send you Trackbacks (we will refer to this as your "Ping URL").

+ +

Your Ping URL must point to a controller function where your Trackback receiving code is located, and the URL +must contain the ID number for each particular entry, so that when the Trackback is received you'll be +able to associate it with a particular entry.

+ +

For example, if your controller class is called Trackback, and the receiving function is called receive, your +Ping URLs will look something like this:

+ +http://www.your-site.com/index.php/trackback/receive/entry_id + +

Where entry_id represents the individual ID number for each of your entries.

+ + +

Creating a Trackback Table

+ +

Before you can receive Trackbacks you must create a table in which to store them. Here is a basic prototype for such a table:

+ + + + +

The Trackback specification only requires four pieces of information to be sent in a Trackback (url, title, excerpt, blog_name), +but to make the data more useful we've added a few more fields in the above table schema (date, IP address, etc.).

+ +

Processing a Trackback

+ +

Here is an example showing how you will receive and process a Trackback. The following +code is intended for use within the controller function where you expect to receive Trackbacks.

+ +$this->load->library('trackback');
+$this->load->database();
+
+if ($this->uri->segment(3) == FALSE)
+{
+    $this->trackback->send_error("Unable to determine the entry ID");
+}
+
+if ( ! $this->trackback->receive())
+{
+    $this->trackback->send_error("The Trackback did not contain valid data");
+}
+
+$data = array(
+                'tb_id'      => '',
+                'entry_id'   => $this->uri->segment(3),
+                'url'        => $this->trackback->data('url'),
+                'title'      => $this->trackback->data('title'),
+                'excerpt'    => $this->trackback->data('excerpt'),
+                'blog_name'  => $this->trackback->data('blog_name'),
+                'tb_date'    => time(),
+                'ip_address' => $this->input->ip_address()
+                );
+
+$sql = $this->db->insert_string('trackbacks', $data);
+$this->db->query($sql);
+
+$this->trackback->send_success(); + +

Notes:

+ +

The entry ID number is expected in the third segment of your URL. This is based on the URI example we gave earlier:

+ +http://www.your-site.com/index.php/trackback/receive/entry_id + +

Notice the entry_id is in the third URI, which you can retrieve using:

+ +$this->uri->segment(3); + +

In our Trackback receiving code above, if the third segment is missing, we will issue an error. Without a valid entry ID, there's no +reason to continue.

+ +

The $this->trackback->receive() function is simply a validation function that looks at the incoming data +and makes sure it contains the four pieces of data that are required (url, title, excerpt, blog_name). +It returns TRUE on success and FALSE on failure. If it fails you will issue an error message.

+ +

The incoming Trackback data can be retrieved using this function:

+ +$this->trackback->data('item') + +

Where item represents one of these four pieces of info: url, title, excerpt, or blog_name

+ +

If the Trackback data is successfully received, you will issue a success message using:

+ +$this->trackback->send_success(); + +

Note: The above code contains no data validation, which you are encouraged to add.

+ + + + + +
+ + + + + + + \ No newline at end of file -- cgit v1.2.3-24-g4f1b