Configuration
- Introduction
- Environment Configuration
- Accessing Configuration Values
- Configuration Caching
- Maintenance Mode
Introduction
All of the configuration files for the Laravel framework are stored in the config
directory. Each option is documented, so feel free to look through the files and get familiar with the options available to you.
Environment Configuration
It is often helpful to have different configuration values based on the environment where the application is running. For example, you may wish to use a different cache driver locally than you do on your production server.
To make this a cinch, Laravel utilizes the DotEnv PHP library by Vance Lucas. In a fresh Laravel installation, the root directory of your application will contain a .env.example
file. If you install Laravel via Composer, this file will automatically be renamed to .env
. Otherwise, you should rename the file manually.
Your .env
file should not be committed to your application's source control, since each developer / server using your application could require a different environment configuration. Furthermore, this would be a security risk in the event an intruder gain access to your source control repository, since any sensitive credentials would get exposed.
If you are developing with a team, you may wish to continue including a .env.example
file with your application. By putting place-holder values in the example configuration file, other developers on your team can clearly see which environment variables are needed to run your application. You may also create a .env.testing
file. This file will override the .env
file when running PHPUnit tests or executing Artisan commands with the --env=testing
option.
Any variable in your .env
file can be overridden by external environment variables such as server-level or system-level environment variables.
Retrieving Environment Configuration
All of the variables listed in this file will be loaded into the $_ENV
PHP super-global when your application receives a request. However, you may use the env
helper to retrieve values from these variables in your configuration files. In fact, if you review the Laravel configuration files, you will notice several of the options already using this helper:
'debug' => env('APP_DEBUG', false),
The second value passed to the env
function is the "default value". This value will be used if no environment variable exists for the given key.
Determining The Current Environment
The current application environment is determined via the APP_ENV
variable from your .env
file. You may access this value via the environment
method on the App
facade:
$environment = App::environment();
You may also pass arguments to the environment
method to check if the environment matches a given value. The method will return true
if the environment matches any of the given values:
if (App::environment('local')) { // The environment is local} if (App::environment(['local', 'staging'])) { // The environment is either local OR staging...}
The current application environment detection can be overridden by a server-level APP_ENV
environment variable. This can be useful when you need to share the same application for different environment configurations, so you can set up a given host to match a given environment in your server's configurations.
Accessing Configuration Values
You may easily access your configuration values using the global config
helper function from anywhere in your application. The configuration values may be accessed using "dot" syntax, which includes the name of the file and option you wish to access. A default value may also be specified and will be returned if the configuration option does not exist:
$value = config('app.timezone');
To set configuration values at runtime, pass an array to the config
helper:
config(['app.timezone' => 'America/Chicago']);
Configuration Caching
To give your application a speed boost, you should cache all of your configuration files into a single file using the config:cache
Artisan command. This will combine all of the configuration options for your application into a single file which will be loaded quickly by the framework.
You should typically run the php artisan config:cache
command as part of your production deployment routine. The command should not be run during local development as configuration options will frequently need to be changed during the course of your application's development.
If you execute the config:cache
command during your deployment process, you should be sure that you are only calling the env
function from within your configuration files. Once the configuration has been cached, the .env
file will not be loaded and all calls to the env
function will return null
.
Maintenance Mode
When your application is in maintenance mode, a custom view will be displayed for all requests into your application. This makes it easy to "disable" your application while it is updating or when you are performing maintenance. A maintenance mode check is included in the default middleware stack for your application. If the application is in maintenance mode, a MaintenanceModeException
will be thrown with a status code of 503.
To enable maintenance mode, execute the down
Artisan command:
php artisan down
You may also provide message
and retry
options to the down
command. The message
value may be used to display or log a custom message, while the retry
value will be set as the Retry-After
HTTP header's value:
php artisan down --message="Upgrading Database" --retry=60
To disable maintenance mode, use the up
command:
php artisan up
You may customize the default maintenance mode template by defining your own template at resources/views/errors/503.blade.php
.
Maintenance Mode & Queues
While your application is in maintenance mode, no queued jobs will be handled. The jobs will continue to be handled as normal once the application is out of maintenance mode.
Alternatives To Maintenance Mode
Since maintenance mode requires your application to have several seconds of downtime, consider alternatives like Envoyer to accomplish zero-downtime deployment with Laravel.