Generating config files

This library can also write configuration back to disk. There are two ways to do this:

• from the command line with config-generate
• from PHP using FileWriter

Generating files from the CLI

The package exposes a binary named config-generate.

vendor/bin/config-generate deploy \
	"database.host=staging-db.internal" \
	"database.schema=shop_branch_42" \
	"stripe.secret_key=secret-for-ci"

This creates a new INI file in the current working directory. The first argument controls the suffix, and the remaining arguments are key-value pairs written using dot notation.

The allowed suffixes are:

• dev
• deploy
• prod

So the above example writes config.deploy.ini.

CLI argument format

Each config value must be written as:

section.key=value

For example:

• app.namespace=MyApp
• database.host=localhost
• exampleapi.key=abc123

If the arguments are invalid, the command writes an error message to standard error.

Within PHP, the Generator class throws Gt\Config\InvalidArgumentException when the suffix or key-value arguments are invalid.

Writing a config file in PHP

If you already have a Config object, use FileWriter to write it as an INI file.

use Gt\Config\Config;
use Gt\Config\ConfigSection;
use Gt\Config\FileWriter;

$config = new Config(
	new ConfigSection("app", [
		"namespace" => "MyApp",
		"debug" => "true",
	]),
	new ConfigSection("database", [
		"host" => "localhost",
		"port" => "3306",
	])
);

$writer = new FileWriter($config);
$writer->writeIni(__DIR__ . "/config.generated.ini");

Any missing directories in the pathname are created automatically.

If the file cannot be written, FileWriter throws Gt\Config\ConfigException.

A note on production file naming

The CLI generator's production suffix is prod, which writes config.prod.ini.

The automatic project loader described earlier looks for config.production.ini.

That means if you want a generated file to be picked up automatically by ConfigFactory::createForProject(), you should either:

• write config.production.ini yourself using FileWriter
• rename the generated config.prod.ini as part of your deployment process

Typical deployment usage

Here we can see how this is useful in continuous integration. A deployment pipeline can create a small override file containing secrets or environment-specific hosts without editing the committed config.ini.

vendor/bin/config-generate deploy \
	"database.host=$DB_HOST" \
	"database.password=$DB_PASSWORD" \
	"shopapi.key=$SHOP_API_KEY"

This keeps the committed config readable while still allowing dynamic values at deploy time.

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If you are using this package inside the wider PHP.Gt framework, continue to Config within WebEngine applications.