Bootstrapping in Zend Framework

In Zend Framework basically request is handled as follows:

   1. Application bootstrapping
   2. Routing
   3. Dispatch

"Bootstrapping" was handled by Zend_Application after that the route(module, controller, and action were requested) was identified in "Routing".  .

In general bootstrapping creates a single entry point for our whole application so it makes our application at the start itself "getting it ready to execute". It'll load all our necessary files as soon as the routing & dispatch is done.


For modules, before routing and dispatch we need some things set up:

• Autoloading support for module resources( view helpers, access to models, access to forms, etc. ) and it'll be enabled by default.
• Setting up module-specific routes. During bootstrapping and before routing occurs this will be specified.
• Module-specific navigation elements. This usually goes hand-in-hand with your routes (most Zend_Navigation pages utilize named routes).
• Setting up module-specific plugins. If there is functionality your module may be needing to enable as part of the routing/dispatch cycle, set this up in plugins and attach them to the front controller.

In the modular structure we can even specify separate bootstrap file for each module. So that we can do things specific to each modules and also we have a master bootstrap file to get full control.


FYI: I have come across one good PDF which explains all about ZF dispatch process - zenddispatch_en.pdf

Here is the exaple for config.ini file.

[production]
phpSettings.display_startup_errors = 1
phpSettings.display_errors = 1
includePaths.library = APPLICATION_PATH "/../library"
bootstrap.path = APPLICATION_PATH "/Bootstrap.php"
bootstrap.class = "Bootstrap"

autoloaderNamespaces[] = "Plugin"
autoloaderNamespaces[] = "Helpers"
autoloaderNamespaces[] = "Validator"

resources.frontController.moduleDirectory = APPLICATION_PATH "/modules"
resources.frontController.params.displayExceptions = 1
resources.frontController.params.prefixDefaultModule = "1"

resources.frontController.actionhelperpaths.Helper_Action = APPLICATION_PATH  "/../library/Helpers/Action"


resources.modules[] =
resources.view[] =
resources.view.helperPath.Helper_View = APPLICATION_PATH "/../library/Helpers/View"

resources.db.adapter = "pdo_mysql"
resources.db.params.host = "localhost"
resources.db.params.username = "username"
resources.db.params.password = "password"
resources.db.params.dbname = "database_name"
resources.db.params.charset = "utf8"
resources.db.params.driver_options.1002 = "SET NAMES utf8"
resources.db.isDefaultTableAdapter = true


resources.layout.layout = "layout"
resources.layout.layoutPath = APPLICATION_PATH "/layouts"


[staging : production]

[testing : production]
phpSettings.display_startup_errors = 1
phpSettings.display_errors = 1

[development : production]
phpSettings.display_startup_errors = 1
phpSettings.display_errors = 1
resources.frontController.params.displayExceptions = 1

How to configure Zend Framework

In Zend Framework you have four ways to use configuration file.

• Zend_Config_Ini
• Zend_Config_Json
• Zend_Config_Xml
• Zend_Config_Yaml

In most of the case everyone will use Zend_Config_In,

Using Zend_Config_Ini you can store configuration information's in the well known INI format and also you can get them in the application by using nested object property syntax. In this INI format we have some hierarchy of configuration data keys and also its possible to inherit between sections. You can use dot or period character (".") to follow hierarchy. A section may extend or inherit from another section by following the section name with a colon character (":") and the name of the section from which data are to be inherited.

[production]
phpSettings.display_startup_errors = 0
phpSettings.display_errors = 0
includePaths.library = APPLICATION_PATH "/../library"
bootstrap.path = APPLICATION_PATH "/Bootstrap.php"
bootstrap.class = "Bootstrap"
appnamespace = "Application"
resources.frontController.controllerDirectory = APPLICATION_PATH "/controllers"
resources.frontController.params.displayExceptions = 0
resources.layout.layoutPath = APPLICATION_PATH "/layouts/scripts/"
resources.view[] =
resources.db.adapter         = pdo_mysql
resources.db.params.host     = localhost 
resources.db.params.username = user_name
resources.db.params.password = user_password
resources.db.params.dbname   = database_name

[staging : production]

[testing : production]
phpSettings.display_startup_errors = 1
phpSettings.display_errors = 1

[development : production]
phpSettings.display_startup_errors = 1
phpSettings.display_errors = 1
resources.frontController.params.displayExceptions = 1 

In the above example, The DB was configured using a hierarchy of keys "resources.db.adapter" also the "Staging" was inherited( [staging : production] ) from "Production". Like this we can define configurations for different environment of our project.

Directory structure in Zend Framework

Using ZF you can create your project as you wish but as its of MVC Architecture we need to follow simple rules like separating model, view & controller. So in order to achieve this you can use any of the two major classification in ZF,


Conventional Directory Structure: You have single MVC to cover your entire project.

index.php
.htaccess
library/
application/
         Bootstrap.php
configs/
     application.ini
layouts/  
     scripts/
          layout.phtml
controllers/                     
         IndexController.php 
         TestController.php
models/
forms/
views/
scripts/   
     index/
        index.phtml            
     test/
        test.phtml            
helpers/
filters/

If your project is big enough to have more modules the basic structure won't fit you so i recommend you guys to follow,

Modular Directory Structure: Its the reliable and very useful directory structure as far as i know, You can use this way to manage projects of any size. And more importantly in this style your entire project can be split up into several modules and it'll be very easy to manage & update individually.

index.php
.htaccess
library/
application/
         Bootstrap.php
configs/
     application.ini
layouts/ 
     scripts/
          layout.phtml
modules/
     default/
          controllers/
                   IndexController.php
                   TestController.php
          models/
          forms/
          views/
             scripts/
                  index/
                     index.phtml
                  test/
                    test.phtml
             helpers/
             filters/
     blog/
       controllers/
                IndexController.php
       models/
       forms/ 
       views/
          scripts/
               index/
                  index.phtml
          helpers/
          filters/

Please remind that either you need to specify "Default" module in configs file else you can create a module "default". With this you can decide about your directory structure in ZF.

In Htaccess file you need to give the following to rewrite all request to index.php by this single entry pont we achieve bootstrapping in ZF.

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} -s [OR]
RewriteCond %{REQUEST_FILENAME} -l [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^.*$ - [NC,L]
RewriteRule ^.*$ index.php [NC,L]