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Calling the extension¶
When a user opens the web page containing our blog in their browser, this request (Request) will be forwarded to the remote TYPO3 Server. Then TYPO3 starts the processing of this request straight away.
A request generally contains the identification number of the page
(the so called Page-ID or PID) that should be generated (e. g.
this PID, TYPO3 searches all relevant content elements on the specific page
and converts these to HTML code one after another. While
processing this page request, TYPO3 comes by the content element for our
example extension, the so called plugin. This plugin should display a list
of all blogs. Each with the individual title, a short description and the
amount of all enclosed posts. In figure 3-4 you can see the output of the
plugin in the frontend. This output is embedded within the greater overview
of the page.
The process of eradication is first forwarded to the dispatcher of Extbase by TYPO3. The dispatcher completes several preliminary tasks before it hands the further processing on to the according position within the code of our blog example:
It interprets the incoming request and bundles all relevant information into a
It prepares the
Responseobject as a container for the result of the request.
It loads the configuration of our extension from the different sources and makes it available.
It determines whether or not the request was manipulated in an illegal manner and when this is the case deflects it (e.g. in of case maliciously added form input field).
It sets up the persistence layer which performs the persisting of new or changed objects.
It prepares the cache in which the content is stored for faster reuse.
It instantiates and configures the controller of our extension which controls further processing within the extension.
When these preparations are fulfilled by the Extbase dispatcher, we
are able to travel to the first stop of our destination: the controller. In
our example all further processing is assigned to the
BlogController. A reference to the
request and the
response is handed over.
BlogController can be found in the
The complete name of the controller is
\MyVendor\BlogExample\Controller\BlogController. At first
this might seem long-winded but the syntax follows a very strict convention
(please see box "Be careful, conventions!").
Be careful, conventions!
The name of a class is separated into individual parts, which
themselves are divided by an underscore. All parts of a class name are
spelled with capital camel case, where each initial letter is capitalized.
This style for notation is commonly known as
UpperCamelCase because each capital letter suggests
the hump of a camel. For extensions the first part always is
Tx". The second part is the name of the extension
- in the underlying case "
BlogExample". The last
part is the name of the domain object. The center between those parts
builds the path to the class file below the folder
Classes. In our case the file is stored directly
within the folder
Controller. The name of the class
file is taken from the last part of the class name appended with the