a1comms/gae-support-l5

Google App Engine & Local SDK Support for Laravel 5.1 apps.

5.1.8 2017-03-27 08:18 UTC

README

Local SDK Support

This package has been changed from shpasser's version for more compatibility for those working with the local GAE SDK.

Join the chat at https://gitter.im/shpasser/GaeSupportL5 Latest Stable Version Total Downloads Latest Unstable Version License

Google App Engine(GAE) Support package for Laravel 5.1.

Currently supported features:

  • Generation of general configuration files,
  • DataStore persistent session handler,
  • Mail service provider,
  • Queue service provider,
  • Database connection,
  • Filesystem,
  • StackDriver Trace API

For Lumen see https://github.com/a1comms/GaeSupportLumen.

Installation

Pull in the package via Composer.

"require": {
    "a1comms/gae-support-l5": "~5.1"
}

Then include the service provider within config/app.php.

'providers' => [
    Shpasser\GaeSupportL5\GaeSupportServiceProvider::class
];

Usage

Generate the GAE related files/entries.

Command template:

php artisan gae:setup --config --cache-config --bucket="your-bucket-id" --db-socket="cloud-sql-instance-socket-connection-string" --db-name="cloud-sql-database-name" --db-host="cloud-sql-instance-ipv4-address" app-id

Arguments and Options:

php artisan gae:setup [options] [--] app-id

Arguments:
  app-id                     GAE application ID.

Options:
      --config               Generate "app.yaml" and "php.ini" config files.
      --cache-config         Generate cached Laravel config file for use on Google App Engine.
      --bucket=BUCKET        Use the specified GCS-bucket instead of the default one.
      --db-socket=DB-SOCKET  Cloud SQL socket connection string for production environment.
      --db-name=DB-NAME      Cloud SQL database name.
      --db-host=DB-HOST      Cloud SQL database host IPv4 address for local environment.

--cache-config option generates cached config file for GAE. This option is essential, because cached config file generated by php artisan config:cache is not suitable for use on GAE. As well, cached config file generated for GAE probably will not work in local environment. This option should be used to generate cached config file before application is deployed on GAE.

--bucket option defines the GCS-bucket ID to be used by the application for storage. Default GCS bucket is configured unless the option is used.

When --db-name option is defined at least one of --db-socket or --db-host should be also defined.

--db-socket is set using the following format: /cloudsql/<app-id>:<cloud-sql-instance-name>. Where <cloud-sql-instance-name> is the Cloud SQL instance name and <app-id> is the name of the application it belongs to.

Persistent Sessions in DataStore

We've included a session driver using DataStore for persistence, cached by memcache for faster access times and reduced billing, giving you the best of both worlds when it comes to speed and persistence.

To make use of this, set:

  • SESSION_DRIVER=gae in .env

This should work without needing to enable billing as long as you don't have heavy usage, as minimal DataStore usage is included free.

You'll probably also want to enable garbage collection to clear out old sessions, which to keep billing at a minimum, we suggest to run once every 24 hours. This will delete any sessions that haven't been updated in 1 week.

To do this, create a cron.yaml file that calls /gae/sessiongc, for example:

cron:
- description: daily session clearout
  url: /gae/sessiongc
  schedule: every day 00:00

If you don't require persistence and are happy with purely memcached, please see the previous session documentation below.

Mail

The mail driver configuration can be found in config/mail.php and .env.production, these configuration files are modified / generated by the artisan command. There is no need in any kind of custom configuration. All the outgoing mail messages are sent with sender address of an administrator of the application, i.e. admin@your-app-id.appspotmail.com. The sender, to, cc, bcc, replyTo, subject, body and attachment parts of email message are supported.

Queues

The modified queue configuration file config/queue.php should contain:

return array(

	...

	/*
	|--------------------------------------------------------------------------
	| GAE Queue Connection
	|--------------------------------------------------------------------------
	|
	*/

	'connections' => array(

		'gae' => array(
			'driver'	=> 'gae',
			'queue'		=> 'default',
			'url'		=> '/tasks',
			'encrypt'	=> true,
		),

		...

	),

);

The 'default' queue and encryption are used by default. In order to use the queue your app/Http/routes.php file should contain the following route:

Route::post('tasks', array('as' => 'tasks',
function()
{
	return Queue::marshal();
}));

This route will be used by the GAE queue to push the jobs. Please notice that the route and the GAE Queue Connection 'url' parameter point to the same URL. Since the requests submitted using the route are issued by GAE itself it cannot be CSRF-protected. For more information on the matter please see http://laravel.com/docs/5.0/queues#push-queues.

Cache, Session and Log

Cache, Session and Log components are supported via the use of specific drivers / handlers:

  • Cache - using the 'memcached' driver,
  • Session - using the 'memcached' driver (or 'gae' for DataStore backed persistence, see above),
  • Log - using 'syslog' handler.

The configuration options for the mentioned drivers / handlers are generated by the artisan command and can be found in .env.production configuration file.

Database

Google Cloud SQL is supported via Laravel's MySql driver. The connection configuration is added by the artisan command to config/database.php under cloudsql. The connection parameters can be configured using --db-socket, --db-name and --db-host options via the artisan command.

The database related environment variables are set in .env.production and .env.local files.

The production environment is configured to use the socket connection while the local configured to connect via the IPv4 address of the Google Cloud SQL instance. Use Google Developers Console in order to obtain the socket connection string and enable the IPv4 address of your database instance.

The migrations are supported while working in local environment only.

To use either the production or the local environment rename the appropriate file to .env.

Filesystem

In order to support Laravel filesystem on GAE the artisan command modifies config/filesystem.php to include an additional disk:

'gae' => [
    'driver' => 'gae',
    'root'   => storage_path().'/app',
],

and adds the following line to .env.production file:

FILESYSTEM = gae

Optimizations

The optimizations allow the application to reduce the use of GCS, which is the only read-write storage available on GAE platform as of now.

In order to optimize view compilation the included cachefs filesystem can be used to store compiled views using memcached service. cachefs does not provide the application with a reliable storage solution, information stored using memcached is managed according to memcached rules and may be deleted when memcached decides to. Since the views can be compiled again without any information loss it is appropriate to store compiled views using cachefs.

cachefs has the following structure:

/
+-- bootstrap
    +-- cache
+-- framework
    +-- views

'/framework/views' is used to store the compiled views.

Use the following option to enable the feature in .env.production and/or .env.local file:

CACHE_COMPILED_VIEWS = true

'/bootstrap/cache' is used to store the services.json, config.php and routes.php files, in order to control caching of these files use the following options in .env.production and/or .env.local file:

CACHE_SERVICES_FILE = true
CACHE_CONFIG_FILE = true
CACHE_ROUTES_FILE = true

In order to use config.php first generate it using the --cache-config option of php artisan gae:setup command. routes.php has to be generated using php artisan route:cache command.

Cache related options are:

  • supported on GAE and/or in local environment as long as memcached service is present,
  • disabled while executing php artisan gae:setup command.

Additionally the initialization of GSC bucket can be skipped to boost the performance. In order to do so, set the following option in the app.yaml file:

env_variables:
        GAE_SKIP_GCS_INIT: true

the storage path will be set to /storage directory of the GCS bucket and storage directory structure creation will be skipped.

If not used the filesystem initialization can be removed to minimize GCS usage. In order to do so, remove the following line from .env.production file:

FILESYSTEM = gae

Google Trace API on App Engine

While running on App Engine, 0.1 requests per seconds per instance are sampled by the StackDriver Trace tool (https://cloud.google.com/trace/docs/faq).

Using the Trace API, we can submit custom time spans to debug performance while running on GAE.

To use, you first need to initialize the class in bootstrap/autoload.php.

Underneath the following:

require __DIR__.'/../vendor/autoload.php';

Add these lines:

/*
|--------------------------------------------------------------------------
| Start our GAE time tracing.
|--------------------------------------------------------------------------
|
| Initiate our GAETrace class to allow us to time trace our code.
| Starting things here will make sure we can trace as much code as possible,
| while ensuring the destructor will always run.
|
*/
use \Shpasser\GaeSupportL5\Trace\GAETrace;
$gae_trace = new GAETrace();

As details in the comments, this will ensure the destructor runs when the code exits, submitting the Trace data to the API.

After this, use of the class is static and can be used from anywhere in the Application.

use \Shpasser\GaeSupportL5\Trace\GAETrace;

//...

$span_id = GAETrace::startSpan("FriendlyName");

//...code here...

GAETrace::endSpan($span_id);

Google have suggested submitting the data to the Trace API asynchronously, which we can do via a Push Queue on App Engine.

For this, we add the following to app.yaml

    - url: /gae/trace_submit
      script: public/trace.php
      login: admin
      secure: always

Create queue.yaml if it doesn't exist with the contents:

queue:
- name: trace
  rate: 5/s
  retry_parameters:
    task_retry_limit: 7
    task_age_limit: 2d

And create the file public/trace.php with the contents:

<?php

/*
|--------------------------------------------------------------------------
| Register The Composer Auto Loader
|--------------------------------------------------------------------------
|
| Composer provides a convenient, automatically generated class loader
| for our application. We just need to utilize it! We'll require it
| into the script here so that we do not have to worry about the
| loading of any our classes "manually". Feels great to relax.
|
*/

require __DIR__.'/../vendor/autoload.php';

use \Shpasser\GaeSupportL5\Trace\GAETrace;
GAETrace::submitTraceAsync();

We are using a different non-Laravel entry point to make sure there is no recursion in submitting traces, which could happen if you've got the core traced and we hit an error before $force_untraced is set.

Artisan Console for GAE

To support artisan commands while running on GAE the package provides Artisan Console for GAE. The console is implemented as a separate service and not enabled by default for security reasons. To use the console securely /artisan route has to be protected.

Installation

Include the service provider within config/app.php.

'providers' => [
    Shpasser\GaeSupportL5\GaeArtisanConsoleServiceProvider::class
];

If it isn't added automatically, add /gae/.* URL handler to app.yaml file.

handlers:

        - url: /gae/.*
          script: public/index.php
          login: admin
          secure: always

        - url: /.*
          script: public/index.php

/gae/.* URL handler has to appear before the last one (url: /.*), otherwise it will be ignored by GAE. The suggested handler secures the route using GAE URL security options. For more information see https://cloud.google.com/appengine/docs/php/config/appconfig#PHP_app_yaml_Secure_URLs.

Usage

Enter URL http://your-app-id.appspot.com/gae/artisan in your browser and use the displayed form to submit artisan commands. Since GAE's filesystem is read-only the commands will not be able to perform write / update operations on it. For the same reason migrations have to be prepared on local development environment before the deployment takes place. Since the console is not really interactive all the commands are executed in non-interactive mode(by automatic appending of -n option).

Deployment

Backup the existing .env file if needed and rename the generated .env.production to .env before deploying your app.

Download and install GAE SDK for PHP and deploy your app.

Known Issues

As of now Laravel scheduled commands are not supported while running on GAE. In order to use Artisan Console for GAE the application class app/Console/Kernel has be edited and any of the commands scheduled using its schedule() function should be removed.