Building web applications is nothing new anymore, as we’ve beendoing it since the early days of the internet, but we’ve alwaysdone this on a single system. Even when Zend Framework came round,we kept doing the same thing and build apps for a singleenvironment.
But as I’ve discussed already in my previous article, developing for the cloud requires anotherapproach.
As you can see, your system now falls appart into all differentcomponents that are systems by themselves. And each system has itsown purpose, completely independent from each other.
With Zend Frameworkdeveloping applications running on these separate compontentsbecomes really easy. It’s like having your cloud toolbox right inyour pocket.
Databases
With Zend Framework,connecting to databases is really easy and swapping out a databasebrand is just a matter of modifying your configurationapplication/configs/application.ini.
resources.db.adapter = "pdo_mysql"resources.db.params.host = "10.20.30.40"resources.db.params.username = "user1"resources.db.params.password = "secret"resources.db.params.dbname = "db1"resources.db.isDefaultTableAdapter = true
Even if you need to connect to multiple databases, you can justpile them up as configuration setting and be done with it.
resources.multidb.server1.adapter = "pdo_mysql"resources.multidb.server1.host = "10.20.30.40"resources.multidb.server1.username = "user1"resources.multidb.server1.password = "secret1"resources.multidb.server1.dbname = "db1"resources.multidb.server1.default = true
resources.multidb.server2.adapter = "pdo_pgsql"resources.multidb.server2.host = "10.20.30.41"resources.multidb.server2.username = "user2"resources.multidb.server2.password = "secret2"resources.multidb.server2.dbname = "db2"
resources.multidb.server3.adapter = "pdo_sqlite"resources.multidb.server3.dbname = APPLICATION_PATH "/files/db/project.db"
But this is just the basics. When dealing with the cloud youoften get a connection string for the host, so it’s real easy tohook up to an relational database in the cloud. Here’s an exampleto connecting to SQL Azure.
resources.db.adapter = "SQLSRV"resources.db.params.host = "abcdefghijk.database.windows.net"resources.db.params.port = 1234resources.db.params.username = "user1"resources.db.params.password = "secret"resources.db.params.dbname = "db1"resources.db.isDefaultTableAdapter = true
Bottom line, no worries connecting to a cloud database. Zend Framework has yourback!
Sessions
As you want to assist your visitors as much as possible, youprobably want to use sessions in your application. If you don’tconfigure anything, PHP stores session on your filesystem bydefault and so does ZendFramework.
For the cloud, you don’t want to write to your local filesystem,so you set up session storage. I chose to use the SQL Azure serverI already had setup using the following settings.
resources.session.use_only_cookies = trueresources.session.gc_maxlifetime = 864000resources.session.remember_me_seconds = 864000resources.session.saveHandler.class = "Zend_Session_SaveHandler_DbTable"resources.session.saveHandler.options.name = "session"resources.session.saveHandler.options.primary = "id"resources.session.saveHandler.options.modifiedColumn = "modified"resources.session.saveHandler.options.dataColumn = "data"resources.session.saveHandler.options.lifetimeColumn = "lifetime"
No further changes need to be done as all fields are defined andthis Zend_Session_SaveHandler_DbTable takes care of all the rest.
Caching
Just like databases, providing caching for your applicationrequires just a few simple configuration settings, this examplesets up a memcache service.
resources.cachemanager.memcached.frontend.name = Coreresources.cachemanager.memcached.frontend.options.automatic_serialization = Onresources.cachemanager.memcached.backend.name = Libmemcachedresources.cachemanager.memcached.backend.options.servers.one.host = localhostresources.cachemanager.memcached.backend.options.servers.one.port = 11211resources.cachemanager.memcached.backend.options.servers.one.persistent = On
Caching on the cloud requires a little different approach as mostcloud services offer their own flavor of caching, making itdifficult to find a PHP driver that is capable to access thiscloud caching layer. But don’t let this stop you in moving to thecloud. Windows Azure provides a superb caching platform, and I’llshow you later in these series how to modify your application asit requires a little tweek on the configuration of your WindowsAzure installation.
Storage
Uploading and distributing files can be considered as an importanpart of any application, and with Zend Framework you canmanage file uploads relatively simple using Zend_Form andZend_File.
An example would be to upload a small image.
public function uploadAction(){ $adapter = new Zend_File_Transfer_Adapter_Http();
$adapter->setDestination(APPLICATION_PATH '/files/upload');
if (!$adapter->receive()) { $messages = $adapter->getMessages(); echo implode("\n", $messages); } $this->view->filename = $adapter->getFileName('avatar', false);}
Saving into a specific location is done with$adapter->setDestination(), but this still requires the usageof a local location! And we know that in the cloud saving locallyhas no use! Luckily for you, ZendFramework has a bunch of components that will allow you tostore files onto a Windows Azure Storage instance.
public function uploadAction() { $config = new Zend_Config_Ini(APPLICATION_PATH . '/configs/api.ini', APPLICATION_ENV);
$azure = new My_Cloud_WindowsAzure_AzureStorage( $config->azure->storage->account, $config->azure->storage->primkey);
$container = $config->azure->storage->container;
$adapter = new Zend_File_Transfer_Adapter_Http(); $adapter->setDestination(APPLICATION_PATH '/files/upload');
if (!$adapter->receive()) { $messages = $adapter->getMessages(); echo implode("\n", $messages); }
$storageClient = new Zend_Service_WindowsAzure_Storage_Blob( My_Cloud_WindowsAzure_AzureStorage::AZURE_STORAGE_HOST, $azure->getAccountName(), $azure->getPrimaryKey());
$result = null;
if (!$storageClient->containerExists($container)) { $result = $storageClient->createContainer($container); $storageClient->setContainerAcl($container, Zend_Service_WindowsAzure_Storage_Blob::ACL_PUBLIC_CONTAINER); }
$fileName = $adapter->getFileName('resume', true); $result = $storageClient->putBlob( $container, basename($fileName), $fileName );
$this->view->filename = basename($fileName); $this->view->location = sprintf('http://%s.%s/%s/%s', $azure->getAccountName(), My_Cloud_WindowsAzure_AzureStorage::AZURE_STORAGE_HOST, $config->azure->storage->container, $result->Name); }
As you can see, you only need to add a little more functionalityto the first example. But once you have everything in place,nothing can stop you achieving your goals.
; These are local configuration settings; Primarily used to access API's using credential tokens[production]...azure.storage.account = "myblobstorageaccount1"azure.storage.primkey = "fjldjljdlfjadladjsljdfljfdljd/akjddfjldfjjd22kajdajfei3234ajldjfjklajlajd=="azure.storage.container = "myblobstoragecontainer"...
[staging: production][testing: production][development: production]
In this example I used an api.ini which is very convenient tostore your most import settings like account names, api keys andpasswords to various api services. It’s just a file containingkey-value pairs for easy configuration. In this case my INIsettings look like the following listing.
Next
Now that we’ve talked about the specific settings in your Zend Framework applicationit’s about time we set up our environment, download all the tools,register for a Windows Azure account and get started with runningour Zend Framework appin the cloud. So stay tuned for more.
