digitalkaoz / dynamicparametersbundle

Runtime retrieval of parameters from environment variables for Symfony

DynamicParametersBundle

This bundle provides a way to read parameters from environment variables at runtime. The value defined in the container parameter is used as fallback when the environment variable is not available.

Installation

Installation is a quick (I promise!) 2 step process:

1. Download IncenteevDynamicParametersBundle
2. Enable the bundle

Step 1: Install IncenteevDynamicParametersBundle with composer

Run the following composer require command:

$ composer require incenteev/dynamic-parameters-bundle

Step 2: Enable the bundle

Finally, enable the bundle in the kernel:

// app/AppKernel.php

public function registerBundles()
{
    $bundles = array(
        // ...
        new Incenteev\DynamicParametersBundle\IncenteevDynamicParametersBundle(),
    );
}

Usage

Define the map of parameter names with the environment variable used to configure them.

# app/config/config.yml
incenteev_dynamic_parameters:
    parameters:
        database_host: DATABASE_HOST
        "database.name": DATABASE_NAME

Environment variables are always strings. To be able to set parameters of other types, the bundle supports parsing the environment variable as inline Yaml:

# app/config/config.yml
incenteev_dynamic_parameters:
    parameters:
        use_ssl:
            variable: HAS_SSL
            yaml: true

ParameterHandler integration

If you are using the env-map feature of the Incenteev ParameterHandler, you can import the whole env-map very easily:

# app/config/config.yml
incenteev_dynamic_parameters:
    import_parameter_handler_map: true
    parameters:
        something_else: NOT_IN_THE_COMPOSER_JSON

The ParameterHandler parses the environment variables as inline Yaml, so the Yaml parsing is automatically enabled for these variables when importing the map.

Note: Any parameter defined explicitly will win over the imported map.

By default, the bundle will look for the composer.json file in %kernel.root_dir%/../composer.json. If you use a non-standard location for your kernel, you can change the path to your composer.json file to read the env-map:

# app/config/config.yml
incenteev_dynamic_parameters:
    import_parameter_handler_map: true
    composer_file: path/to/composer.json

Retrieving parameters at runtime

The bundle taks care of service arguments, but changing the behavior of $container->getParameter() is not possible. However, it exposes a service to get parameters taking the environment variables into account.

$this->get('incenteev_dynamic_parameters.retriever')->get('use_ssl');

Limitations

• Getting a parameter from the container directly at runtime will not use the environment variable
• Parameters or arguments built by concatenating other parameters together will not rely on the environment variables (yet)